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Jessie Atterholt

Jessie Atterholt, Ph.D.

Associate Professor

College of Osteopathic Medicine of the Pacific

Western University of Health Sciences

Pomona, CA, USA

jessie.atterholt@gmail.com

Home: Welcome

Hawk Dissection Part 6. I took a break from research to make something pretty. 😊 I never tire of musculoskeletal anatomy, and had a lot of fun figuring out what was going on here:
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On the shoulder and upper arm:
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chartreuse - pectoralis m.
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purple - biceps brachii m.
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teal - deltoid m.
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pink - tensor propatagialis m.
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orange - scapulotriceps m.
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Most of these are muscles we also have, but birds have a special tensor propatagialis muscle that humans don’t. This is actually part of the deltoid, and it attaches to the membrane of skin that stretches between the arm and forearm (called the patagium). This muscle helps the bird alter the tension in the patagium, thus aiding in control of flight!
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Forearm muscles:
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blue - extensor carpi radialis m.
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red - extensor digitorum communis m.
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yellow - extensor carpi ulnaris m.
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green - supinator m.
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These are muscles that extend the wrist (extensor carpi radialis and ulnaris) and the fingers (extensor digitorum). You also have these muscles in your forearm!
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The supinator is extra cool. This muscle is what allows you to rotate your forearm so your palms can face up!
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#science #scicomm #birdsofinstagram #hawk #anatomy #comparativeanatomy #dissection #livingdinosaur #supination #biceps #deltoids #pecs #muscles

Hawk Dissection Part 6. I took a break from research to make something pretty. 😊 I never tire of musculoskeletal anatomy, and had a lot of fun figuring out what was going on here:
.
On the shoulder and upper arm:
.
chartreuse - pectoralis m.
.
purple - biceps brachii m.
.
teal - deltoid m.
.
pink - tensor propatagialis m.
.
orange - scapulotriceps m.
.
Most of these are muscles we also have, but birds have a special tensor propatagialis muscle that humans don’t. This is actually part of the deltoid, and it attaches to the membrane of skin that stretches between the arm and forearm (called the patagium). This muscle helps the bird alter the tension in the patagium, thus aiding in control of flight!
.
Forearm muscles:
.
blue - extensor carpi radialis m.
.
red - extensor digitorum communis m.
.
yellow - extensor carpi ulnaris m.
.
green - supinator m.
.
These are muscles that extend the wrist (extensor carpi radialis and ulnaris) and the fingers (extensor digitorum). You also have these muscles in your forearm!
.
The supinator is extra cool. This muscle is what allows you to rotate your forearm so your palms can face up!
.
#science #scicomm #birdsofinstagram #hawk #anatomy #comparativeanatomy #dissection #livingdinosaur #supination #biceps #deltoids #pecs #muscles

Hawk Dissection Part 5. Time for some muscle anatomy! (You didn’t think we were finished with this guy yet, did you??)
.
Here you see the dorsal side of the hawk (the back) just after I skinned it and before I tore all of this apart in my botched laminectomy. These are the muscles we can see (from the front by the neck, to the back by the tail):
.
Blue: superficial rhomboid (pulls scapulae together)
.
Yellow: latissimus dorsi (yep, as in “lats”)
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Pink and teal: iliotibialis, cranial and lateral parts respectively (goes from the hip to the knee)
.
Purple: levator caudae (lifts the tail!)
.
Lovely, right? Some of these muscles are in humans, too (like the rhomboids and latissimus dorsi). The others are not found in us, but would have been present in extinct dinosaurs! (Swipe for the unlabeled version to test your identification skills!)
.
So how do you identify muscles, anyway? And how can we possibly figure out what muscles on a fossil critter looked like? The answer to both questions lies in paying attention to attachment points of the muscles.
.
When doing a dissection, looking at what parts if the skeleton a muscle attaches to is key to figuring out its identity. For instance, here I knew what the rhomboid was because I saw a muscle that attached to the spine and to the scapula (shoulder bone), whereas the latissimus dorsi goes from the lower back to the humerus (upper arm bone).
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Muscles often leave marks on bone where they attach (a bump, a line, a rough patch) so we can use these clues to reconstruct muscles in extinct organisms!
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#science #anatomy #muscles #lats #hawk #birdsofinstagram #scicomm #comparativeanatomy #livingdinosaur #vetmed #paleontology #bird

Hawk Dissection Part 5. Time for some muscle anatomy! (You didn’t think we were finished with this guy yet, did you??)
.
Here you see the dorsal side of the hawk (the back) just after I skinned it and before I tore all of this apart in my botched laminectomy. These are the muscles we can see (from the front by the neck, to the back by the tail):
.
Blue: superficial rhomboid (pulls scapulae together)
.
Yellow: latissimus dorsi (yep, as in “lats”)
.
Pink and teal: iliotibialis, cranial and lateral parts respectively (goes from the hip to the knee)
.
Purple: levator caudae (lifts the tail!)
.
Lovely, right? Some of these muscles are in humans, too (like the rhomboids and latissimus dorsi). The others are not found in us, but would have been present in extinct dinosaurs! (Swipe for the unlabeled version to test your identification skills!)
.
So how do you identify muscles, anyway? And how can we possibly figure out what muscles on a fossil critter looked like? The answer to both questions lies in paying attention to attachment points of the muscles.
.
When doing a dissection, looking at what parts if the skeleton a muscle attaches to is key to figuring out its identity. For instance, here I knew what the rhomboid was because I saw a muscle that attached to the spine and to the scapula (shoulder bone), whereas the latissimus dorsi goes from the lower back to the humerus (upper arm bone).
.
Muscles often leave marks on bone where they attach (a bump, a line, a rough patch) so we can use these clues to reconstruct muscles in extinct organisms!
.
#science #anatomy #muscles #lats #hawk #birdsofinstagram #scicomm #comparativeanatomy #livingdinosaur #vetmed #paleontology #bird

Hawk Dissection Part 4. I promise, there is a gem amid this mess! Oftentimes a dissection can end with you pulling a specimen apart so much that it’s tough to even identify major body parts anymore, as is the case here, but the mess is all to see something extremely cool.
.
Here it is: the avian lumbosacral plexus!!! In my last post I shared the brachial plexus, which is the nerve supply to the upper limb and shoulder. This is essentially its counterpart, a mess of big, fat nerves that supply the hip region and the hindlimb. In birds, this typically consists of 7 nerves, 6 of which we can see here.
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There is less crazy merging and separating than in the brachial plexus, but some nerves do come together. For instance, some of these will combine to form the sciatic nerve, a major nerve of the leg. Yep, sciatic as in “sciatica”! We also have a sciatic nerve, and a lumbosacral plexus!
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I had to break open the synsacrum (fused hip bones and lower back vertebrae) to see this. Fun fact: I did this entire dissection using only a good pair of dissecting scissors and rat-tooth forceps, no scalpel required! (Thanks @paleofox — still using the set you gave me!!)
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#science #anatomy #dissection #hawk #birdsofinstagram #comparativeanatomy #lumbosacral #nerves #vetmed #scicomm

Hawk Dissection Part 4. I promise, there is a gem amid this mess! Oftentimes a dissection can end with you pulling a specimen apart so much that it’s tough to even identify major body parts anymore, as is the case here, but the mess is all to see something extremely cool.
.
Here it is: the avian lumbosacral plexus!!! In my last post I shared the brachial plexus, which is the nerve supply to the upper limb and shoulder. This is essentially its counterpart, a mess of big, fat nerves that supply the hip region and the hindlimb. In birds, this typically consists of 7 nerves, 6 of which we can see here.
.
There is less crazy merging and separating than in the brachial plexus, but some nerves do come together. For instance, some of these will combine to form the sciatic nerve, a major nerve of the leg. Yep, sciatic as in “sciatica”! We also have a sciatic nerve, and a lumbosacral plexus!
.
I had to break open the synsacrum (fused hip bones and lower back vertebrae) to see this. Fun fact: I did this entire dissection using only a good pair of dissecting scissors and rat-tooth forceps, no scalpel required! (Thanks @paleofox — still using the set you gave me!!)
.
#science #anatomy #dissection #hawk #birdsofinstagram #comparativeanatomy #lumbosacral #nerves #vetmed #scicomm

Hawk Dissection Part 3. BRACHIAL PLEXUS TIME. I am SOOOO EXCITED to share this extra cool anatomy photo today! This is possibly my favorite post to-date. May I present to you:
.
In teal: the avian brachial plexus!!! 😄😄😄
.
In red: major arteries of the shoulder and wing
.
As any anatomy student will fondly recall 😉, the brachial plexus is a complex set of nerves that supplies the shoulder and arm. These nerves branch off the spinal cord, but then they actually come together, split, then come together again in complex ways.
.
Like birds, we, too, have a brachial plexus. In birds the nerves that form this structure are those at the very base of the neck and the upper back (typically spinal nerves 11-15). In humans, it’s usually formed mostly from nerves coming off the neck. Fun fact: this is why neck injury can actually result in things like numbing and/or muscle weakness in the arm and shoulder!
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We can also see something cool going on with the arteries. My finger is on the lung, and the heart is just on the other side of it. We’re seeing one of the major vessels coming off the heart (the brachiocephalic a.), as it becomes the axillary a. in the armpit and then the brachial a. on the arm. You can also see lots of other smaller branches coming off these vessels. These are all vessels present in your body, as well.
.
Swipe for the unlabeled version if you want to test your eye for finding anatomical structures! Have you ever seen anything more #beautiful ?? 😍
.
#science #brachialplexus #hawk #birdsofinstagram #vetmed #anatomy #comparativeanatomy #dissection #scicomm #scienceart

Hawk Dissection Part 3. BRACHIAL PLEXUS TIME. I am SOOOO EXCITED to share this extra cool anatomy photo today! This is possibly my favorite post to-date. May I present to you:
.
In teal: the avian brachial plexus!!! 😄😄😄
.
In red: major arteries of the shoulder and wing
.
As any anatomy student will fondly recall 😉, the brachial plexus is a complex set of nerves that supplies the shoulder and arm. These nerves branch off the spinal cord, but then they actually come together, split, then come together again in complex ways.
.
Like birds, we, too, have a brachial plexus. In birds the nerves that form this structure are those at the very base of the neck and the upper back (typically spinal nerves 11-15). In humans, it’s usually formed mostly from nerves coming off the neck. Fun fact: this is why neck injury can actually result in things like numbing and/or muscle weakness in the arm and shoulder!
.
We can also see something cool going on with the arteries. My finger is on the lung, and the heart is just on the other side of it. We’re seeing one of the major vessels coming off the heart (the brachiocephalic a.), as it becomes the axillary a. in the armpit and then the brachial a. on the arm. You can also see lots of other smaller branches coming off these vessels. These are all vessels present in your body, as well.
.
Swipe for the unlabeled version if you want to test your eye for finding anatomical structures! Have you ever seen anything more #beautiful ?? 😍
.
#science #brachialplexus #hawk #birdsofinstagram #vetmed #anatomy #comparativeanatomy #dissection #scicomm #scienceart

Hawk Dissection Part 2. Sometimes tiny, delicate structures are the coolest. The first thing I saw in my hawk dissection after skinning the back (and before ripping apart the muscles and bones) was these perfectly lovely little nerves! They are highlighted in teal on the hawk’s left, and my scissors are pointing to one on the right.
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These are cutaneous branches of the dorsal rami of the spinal nerves. In other words, they are cute little nerves that innervate superficial structures like the skin.
.
I was delighted to see them, because these are also some of the very first structures my students look for when we start a cadaver dissection! People, too, have cute little pairs of superficial nerves that go all the way down the back. Swipe for a drawing of what these nerves look like in us from my favorite anatomical atlas (Netter’s)!
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#science #comparativeanatomy #hawk #nerves #vetmed #anatomy #birdsofinstagram #birds #dissection #scicomm

Hawk Dissection Part 2. Sometimes tiny, delicate structures are the coolest. The first thing I saw in my hawk dissection after skinning the back (and before ripping apart the muscles and bones) was these perfectly lovely little nerves! They are highlighted in teal on the hawk’s left, and my scissors are pointing to one on the right.
.
These are cutaneous branches of the dorsal rami of the spinal nerves. In other words, they are cute little nerves that innervate superficial structures like the skin.
.
I was delighted to see them, because these are also some of the very first structures my students look for when we start a cadaver dissection! People, too, have cute little pairs of superficial nerves that go all the way down the back. Swipe for a drawing of what these nerves look like in us from my favorite anatomical atlas (Netter’s)!
.
#science #comparativeanatomy #hawk #nerves #vetmed #anatomy #birdsofinstagram #birds #dissection #scicomm

Hawk Dissection Part 1. Doing science so often doesn’t work out the way we want or expect. I put this small hawk in acetone to fix the soft tissues a few months ago. My plan was to cut open the skull to seen the brain, and cut open the vertebrae to see the spinal cord (basically, do a laminectomy). The central nervous system decays VERY rapidly, and was too far gone when I put it in, so even with the acetone my plan didn’t work. ☹️ The brain was really crumbly and fell into pieces, and the spinal cord was just mush. But all was not lost!
.
To do the laminectomy and cut open the skull, I had been dissecting from the dorsal side of the animal (the back). I basically removed all of the muscles from the back as well as the ribs and most of the bone of the vertebrae. And I was left with a pretty cool dissection!
.
From this approach, you can see organs that are held deep in the body cavity against the back body wall, like the lungs and kidneys (birds have three-lobed kidneys, and we can see the anterior and posterior lobes here). The uropygial glands are also nicely preserved. These are glands on bird rumps that secrete oils they use to preen their feathers.
.
Pretty cool, right? But oh, this little guy has SO many more anatomical treasures...Stay tuned for even more cool stuff!
.
#hawk #anatomy #dissection #ornithology #birdsofinstagram #livingdinosaur #science

Hawk Dissection Part 1. Doing science so often doesn’t work out the way we want or expect. I put this small hawk in acetone to fix the soft tissues a few months ago. My plan was to cut open the skull to seen the brain, and cut open the vertebrae to see the spinal cord (basically, do a laminectomy). The central nervous system decays VERY rapidly, and was too far gone when I put it in, so even with the acetone my plan didn’t work. ☹️ The brain was really crumbly and fell into pieces, and the spinal cord was just mush. But all was not lost!
.
To do the laminectomy and cut open the skull, I had been dissecting from the dorsal side of the animal (the back). I basically removed all of the muscles from the back as well as the ribs and most of the bone of the vertebrae. And I was left with a pretty cool dissection!
.
From this approach, you can see organs that are held deep in the body cavity against the back body wall, like the lungs and kidneys (birds have three-lobed kidneys, and we can see the anterior and posterior lobes here). The uropygial glands are also nicely preserved. These are glands on bird rumps that secrete oils they use to preen their feathers.
.
Pretty cool, right? But oh, this little guy has SO many more anatomical treasures...Stay tuned for even more cool stuff!
.
#hawk #anatomy #dissection #ornithology #birdsofinstagram #livingdinosaur #science

Why hello there! I hope this finds you safe and healthy during these scary times. I’ve had a bit of an Instagram hiatus for lots of reasons—my job got crazy busy, I hate social media, and I moved. The exciting thing about moving is rediscovering stuff you forgot you had when you unpack.
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In my case, that was an old terrarium that I used to keep my dermestid beetles in. While no longer containing living beetles, it did have their last meal: a baby cobra!!! I was ecstatic to discover this lovely little skeleton. Swipe for a couple images from his photoshoot (including a cool one of the underside of his skull, where you can see his fangs).
.
Lastly, check out some lovely figures from a REALLY cool paper I recently read by Zippel et al. (2001) on veins around the vertebrae in snakes. These images are latex casts of the vertebral venous plexus—basically, a complex set of interconnected veins around and within the vertebral column. For those interested: VVP=vertebral venous plexus; ICV=intercostal vein; AVV=anterior vertrbral vein. So beautiful and fascinating.
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#cobra #snakesofinstagram #science #scicomm #anatomy #skeleton #snake

Why hello there! I hope this finds you safe and healthy during these scary times. I’ve had a bit of an Instagram hiatus for lots of reasons—my job got crazy busy, I hate social media, and I moved. The exciting thing about moving is rediscovering stuff you forgot you had when you unpack.
.
In my case, that was an old terrarium that I used to keep my dermestid beetles in. While no longer containing living beetles, it did have their last meal: a baby cobra!!! I was ecstatic to discover this lovely little skeleton. Swipe for a couple images from his photoshoot (including a cool one of the underside of his skull, where you can see his fangs).
.
Lastly, check out some lovely figures from a REALLY cool paper I recently read by Zippel et al. (2001) on veins around the vertebrae in snakes. These images are latex casts of the vertebral venous plexus—basically, a complex set of interconnected veins around and within the vertebral column. For those interested: VVP=vertebral venous plexus; ICV=intercostal vein; AVV=anterior vertrbral vein. So beautiful and fascinating.
.
#cobra #snakesofinstagram #science #scicomm #anatomy #skeleton #snake

About this time last year I cut a pig head in two (some of you may recall the pics!). Half was skeletonized, the other half was plastinated. This (clearly) is the latter. It might look like it’s from a Lord of the Flies nightmare, but as usual I find much beauty in the anatomy.
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I spent waaaay too much time dissecting it, so the muscle came out kinda dry and jerky-like. Not my best work, but it’s been used for something really cool! My colleague Gary Wisser, who works in the 3d Visualization Department here are WesternU, did a surface scan of the pig head and created an awesome 3d model!! 😄 Swipe to see screen shots Gary’s model, compared with the real head. I daresay they almost look better...
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#pig #anatomy #science #plastination #lordoftheflies #westernuniversityofhealthsciences #head #uglybeautiful

About this time last year I cut a pig head in two (some of you may recall the pics!). Half was skeletonized, the other half was plastinated. This (clearly) is the latter. It might look like it’s from a Lord of the Flies nightmare, but as usual I find much beauty in the anatomy.
.
I spent waaaay too much time dissecting it, so the muscle came out kinda dry and jerky-like. Not my best work, but it’s been used for something really cool! My colleague Gary Wisser, who works in the 3d Visualization Department here are WesternU, did a surface scan of the pig head and created an awesome 3d model!! 😄 Swipe to see screen shots Gary’s model, compared with the real head. I daresay they almost look better...
.
#pig #anatomy #science #plastination #lordoftheflies #westernuniversityofhealthsciences #head #uglybeautiful

Last night I experienced one of the highlights of my professional career this far: an exhibit at the Western Science Center on one of my research collaboration. It. Is. INCREDIBLE.
.
This is a unique exhibit. The genius behind it is my good friend and colleague Dr. Alton Cooley, executive director of the museum. He had the idea to bring cutting edge research to the public directly from the scientists who are doing it. My collaborators Dr. Matt Wedel and Dr. Thierra Nalley have been intimately involved in the making of this exhibit (...while I’ve been swamped with teaching duties!). Alton’s idea was to create an exhibit that is like the way artists share their work at exhibitions, a new way for scientists to share research with the public, and to humanize that work by putting a face to it. In my humble opinion, it is absolutely brilliant. .
On to the displays! This exhibit is called “Tiny Titan” because it features our work Haplocanthosaurus, a sauropod with a relatively small body size. This specimen consists only of a handful of smashed vertebrae from the tail and hip regions, but we’ve made some fascinating discoveries by CT scanning and reconstructing them. .
The inimitable Brian Engh (@brianengh_art ) drew for us an absolutely gorgeous reconstruction of the dinosaur (see 2nd image). You can compare the size of a Haplocanthosaurus vertebra to a massive Apatosaurus vertebra (3rd image). We discovered the bones are pneumatic—meaning they are filled with air just like bird bones (4th image)! AND we reconstructed some truly bizarre soft tissues associated with the vertebrae: massive cartilage discs between them, and a weird, bulgy spinal cord (5th image). Alton made a 3D print reconstruction (6th image)!! And the final pic is of Dr. Cooley himself, rocking a custom tie featuring Brian’s reconstruction of the dinosaur!!
.
That’s not the entire exhibit, just some of the highlights. Go see it yourself if you can! It is visually stunning, and was made entirely in house! Mind blown.
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Exhibits like this are the future. I’m beyond excited and deeply honored to be a part of this.

Last night I experienced one of the highlights of my professional career this far: an exhibit at the Western Science Center on one of my research collaboration. It. Is. INCREDIBLE.
.
This is a unique exhibit. The genius behind it is my good friend and colleague Dr. Alton Cooley, executive director of the museum. He had the idea to bring cutting edge research to the public directly from the scientists who are doing it. My collaborators Dr. Matt Wedel and Dr. Thierra Nalley have been intimately involved in the making of this exhibit (...while I’ve been swamped with teaching duties!). Alton’s idea was to create an exhibit that is like the way artists share their work at exhibitions, a new way for scientists to share research with the public, and to humanize that work by putting a face to it. In my humble opinion, it is absolutely brilliant. .
On to the displays! This exhibit is called “Tiny Titan” because it features our work Haplocanthosaurus, a sauropod with a relatively small body size. This specimen consists only of a handful of smashed vertebrae from the tail and hip regions, but we’ve made some fascinating discoveries by CT scanning and reconstructing them. .
The inimitable Brian Engh (@brianengh_art ) drew for us an absolutely gorgeous reconstruction of the dinosaur (see 2nd image). You can compare the size of a Haplocanthosaurus vertebra to a massive Apatosaurus vertebra (3rd image). We discovered the bones are pneumatic—meaning they are filled with air just like bird bones (4th image)! AND we reconstructed some truly bizarre soft tissues associated with the vertebrae: massive cartilage discs between them, and a weird, bulgy spinal cord (5th image). Alton made a 3D print reconstruction (6th image)!! And the final pic is of Dr. Cooley himself, rocking a custom tie featuring Brian’s reconstruction of the dinosaur!!
.
That’s not the entire exhibit, just some of the highlights. Go see it yourself if you can! It is visually stunning, and was made entirely in house! Mind blown.
.
Exhibits like this are the future. I’m beyond excited and deeply honored to be a part of this.

Part 6: Atterholt and Wedel, SVPCA 2019. (Did you think it was over?! 😉)
.
If you’ve been following this series of posts, you know that Matt and I decided the best explanation of neural canal ridges in sauropod tail vertebrae is that they are bony spinal cord supports, which denticulate ligaments attached to.
.
Yay! But why do we only see them in the tail vertebrae? And why do bony spinal cord supports appear in sauropods and fish and salamanders, but not really other critters??
.
To properly answer these questions there is lots more work to be done. One idea we have is that they provide extra support for the spinal cord in parts of the vertebral column that move side to side a lot (aka, laterally).
.
Many sauropods used their tails as weapons in various ways, which would involve strong and fast lateral movement. And fish and salamanders wiggle their bodies side-to-side to swim/walk.
.
Then again, we recently discovered bony spinal cord supports in the tail vertebra of a hadrosaur (duck-billed dino), which was decidedly NOT moving its tail laterally very much—it is stabilized by a bunch of ossified tendons which reduce this kind of movement. Also...why are spinal cord supports biggest in short little amphibian necks what can’t move a lot and smallest in the tails? And...not all fish actually move the whole spine side-to-side when they swim...Hmmmm.
.
For now, who knows why spinal cord supports appear in some animals and not other? 🤷🏻‍♀️Maybe they have multiple functions? Maybe no function at all?? We’re continuing research on this project to find out!
.
#paleontology #comparativeanatomy #sauropod #hadrosaur #science #anatomy #vertebrae #fish #salamander #svpca2019 @mathew.wedel

Part 6: Atterholt and Wedel, SVPCA 2019. (Did you think it was over?! 😉)
.
If you’ve been following this series of posts, you know that Matt and I decided the best explanation of neural canal ridges in sauropod tail vertebrae is that they are bony spinal cord supports, which denticulate ligaments attached to.
.
Yay! But why do we only see them in the tail vertebrae? And why do bony spinal cord supports appear in sauropods and fish and salamanders, but not really other critters??
.
To properly answer these questions there is lots more work to be done. One idea we have is that they provide extra support for the spinal cord in parts of the vertebral column that move side to side a lot (aka, laterally).
.
Many sauropods used their tails as weapons in various ways, which would involve strong and fast lateral movement. And fish and salamanders wiggle their bodies side-to-side to swim/walk.
.
Then again, we recently discovered bony spinal cord supports in the tail vertebra of a hadrosaur (duck-billed dino), which was decidedly NOT moving its tail laterally very much—it is stabilized by a bunch of ossified tendons which reduce this kind of movement. Also...why are spinal cord supports biggest in short little amphibian necks what can’t move a lot and smallest in the tails? And...not all fish actually move the whole spine side-to-side when they swim...Hmmmm.
.
For now, who knows why spinal cord supports appear in some animals and not other? 🤷🏻‍♀️Maybe they have multiple functions? Maybe no function at all?? We’re continuing research on this project to find out!
.
#paleontology #comparativeanatomy #sauropod #hadrosaur #science #anatomy #vertebrae #fish #salamander #svpca2019 @mathew.wedel

Part 5 of Atterholt and Wedel, SVPCA 2019 (I promise, this is almost over...!)
.
To understand our next idea to explain bony neural canal ridges in the tail vertebrae of sauropods, let’s talk a little about #neuroanatomy .
.
The brain and spinal cord (of you and your dog and a dinosaur and a fish) are surrounded by three layers of tissue: 1) dura mater (=“tough mother”), the outermost protective layer; 2) arachnoid mater (=“spider web mother”) in the middle, which encloses the subarachnoid space full of cerebrospinal fluid; and the pia mater (=“soft mother”), the delicate innermost layer directly fused to the spinal cord. The pia mater has segmental projections out to the side called denticulate ligaments, which attach to the dura mater and support the spinal cord. .
Whew! Okay, now that we’re clear on denticulate ligaments (hopefully), here’s the cool/weird thing about them: in some modern animals they actually attach to bony projections in the neural canal!!! These bony spinal cord supports have been documented in many salamanders and bony fish. And guess what else? They vary in size and position across different animals and through vertebral regions.
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So at long last, we have a winner! Bony spinal cord supports meet almost all of the descriptive criteria of neural canal ridges in sauropods, so we think they are there to give extra support to the spinal cord in the tail. .
Last image is my reconstruction of these soft tissues. You can see the dura mater fused to the bone of the neural canal, and the denticulate ligaments of pia mater attaching to the dura mater and bony spinal cord supports.
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We were able to learn something about soft tissue neuroanatomy in dinosaurs by studying the skeleton! 🎉 And we used comparative anatomy to do it. 🤗
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#science #paleontology #anatomy #sauropod #spinalcord #research #vertebrae #fossil #svpca2019 @mathew.wedel

Part 5 of Atterholt and Wedel, SVPCA 2019 (I promise, this is almost over...!)
.
To understand our next idea to explain bony neural canal ridges in the tail vertebrae of sauropods, let’s talk a little about #neuroanatomy .
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The brain and spinal cord (of you and your dog and a dinosaur and a fish) are surrounded by three layers of tissue: 1) dura mater (=“tough mother”), the outermost protective layer; 2) arachnoid mater (=“spider web mother”) in the middle, which encloses the subarachnoid space full of cerebrospinal fluid; and the pia mater (=“soft mother”), the delicate innermost layer directly fused to the spinal cord. The pia mater has segmental projections out to the side called denticulate ligaments, which attach to the dura mater and support the spinal cord. .
Whew! Okay, now that we’re clear on denticulate ligaments (hopefully), here’s the cool/weird thing about them: in some modern animals they actually attach to bony projections in the neural canal!!! These bony spinal cord supports have been documented in many salamanders and bony fish. And guess what else? They vary in size and position across different animals and through vertebral regions.
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So at long last, we have a winner! Bony spinal cord supports meet almost all of the descriptive criteria of neural canal ridges in sauropods, so we think they are there to give extra support to the spinal cord in the tail. .
Last image is my reconstruction of these soft tissues. You can see the dura mater fused to the bone of the neural canal, and the denticulate ligaments of pia mater attaching to the dura mater and bony spinal cord supports.
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We were able to learn something about soft tissue neuroanatomy in dinosaurs by studying the skeleton! 🎉 And we used comparative anatomy to do it. 🤗
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#science #paleontology #anatomy #sauropod #spinalcord #research #vertebrae #fossil #svpca2019 @mathew.wedel

Part 4 of Atterholt and Wedel, SVPCA 2019: a quest to understand neural canal ridges in the tails of sauropod dinosaurs.
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After a couple ideas that didn’t pan out, we took a closer look at bony ridges that separate the spinal cord from other soft tissues in modern birds and crocodylians. This seemed promising, because they are bony ridges actually in the canal and located on the sides of the wall. So far, so good!
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In crocs and alligators this bony ridge separates the spinal cord from a large dorsal spinal vein. In bird, it separates the spinal cord from paramedullary airways, a fancy term for parts of the respiratory system that contact the spinal cord and sometimes enter the vertebral canal! I know, it’s really weird.
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However...this idea, too, didn’t pan out. These ridges in crocs and birds extend aaallll the way to the ends of the vertebral canals (since the soft tissues they separate pass through multiple vertebrae, this makes sense). As a result, they change the shape of the canals. Can you see how they are 8-shaped? This is also NOT what we were seeing in the tail vertebrae of sauropods.
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#science #anatomy #comparativeanatomy #vertebrae #dinosaur #sauropod #svpca2019 @mathew.wedel

Part 4 of Atterholt and Wedel, SVPCA 2019: a quest to understand neural canal ridges in the tails of sauropod dinosaurs.
.
After a couple ideas that didn’t pan out, we took a closer look at bony ridges that separate the spinal cord from other soft tissues in modern birds and crocodylians. This seemed promising, because they are bony ridges actually in the canal and located on the sides of the wall. So far, so good!
.
In crocs and alligators this bony ridge separates the spinal cord from a large dorsal spinal vein. In bird, it separates the spinal cord from paramedullary airways, a fancy term for parts of the respiratory system that contact the spinal cord and sometimes enter the vertebral canal! I know, it’s really weird.
.
However...this idea, too, didn’t pan out. These ridges in crocs and birds extend aaallll the way to the ends of the vertebral canals (since the soft tissues they separate pass through multiple vertebrae, this makes sense). As a result, they change the shape of the canals. Can you see how they are 8-shaped? This is also NOT what we were seeing in the tail vertebrae of sauropods.
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#science #anatomy #comparativeanatomy #vertebrae #dinosaur #sauropod #svpca2019 @mathew.wedel

Atterholt and Wedel, SVPCA 2019 Part 3.
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Matt and I both teach human anatomy for a living (#dreamjob) and we got to thinking about ligaments that attach vertebrae to each other as a possible explanation for the weird bony ridges in tail vertebrae of long-necked dinosaurs. Ligaments (strong sheets or bands of connective tissue) often leave behind rough patches and pokey-outy bits on bones where they attach.
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Matt’s awesome wife Dr. Vicki Wedel (who is a forensic anthropologist!) suggested the ridges could be scars for the attachment of the ligamentum flavum, which attaches consecutive vertebrae to each other along the top of the arches.
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But when we examined bony projections on modern bones we found they were on the roof and ends of the vertebral canal, so not in the right place. 😕 And upon further research we also learned that the ligamentum flavum is only in mammals! So it’s unlikely it was present in a dinosaur. Another wrong idea. #science .
But that’s okay, cause we had more ideas...
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#vertebrae #paleontology #dinosaur #mammal #sauropod #anatomy #comparativeanatomy #ligaments #bones #svpca2019 @mathew.wedel

Atterholt and Wedel, SVPCA 2019 Part 3.
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Matt and I both teach human anatomy for a living (#dreamjob) and we got to thinking about ligaments that attach vertebrae to each other as a possible explanation for the weird bony ridges in tail vertebrae of long-necked dinosaurs. Ligaments (strong sheets or bands of connective tissue) often leave behind rough patches and pokey-outy bits on bones where they attach.
.
Matt’s awesome wife Dr. Vicki Wedel (who is a forensic anthropologist!) suggested the ridges could be scars for the attachment of the ligamentum flavum, which attaches consecutive vertebrae to each other along the top of the arches.
.
But when we examined bony projections on modern bones we found they were on the roof and ends of the vertebral canal, so not in the right place. 😕 And upon further research we also learned that the ligamentum flavum is only in mammals! So it’s unlikely it was present in a dinosaur. Another wrong idea. #science .
But that’s okay, cause we had more ideas...
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#vertebrae #paleontology #dinosaur #mammal #sauropod #anatomy #comparativeanatomy #ligaments #bones #svpca2019 @mathew.wedel

Part 2 of Atterholt and Wedel, SVPCA 2019. (My Instagram “presenting” of a talk I recently gave at a paleontology conference.)
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In my last post I shared that my coauthor and I discovered weird bony ridges in the neural canals of sauropods. Our next task was to figure out what they are!
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Our first idea was that they might form at neurocentral joints. What the heck does that mean?? Well, in early development, all vertebrates (animals with a back bone) have vertebrae in two major pieces: the round centrum on the bottom (this forms the biggest joint between consecutive vertebrae) and the thin bony arch above it. They will ossify and fuse together as an animal grows. We thought neural canal ridges might be part of the suture between these two pieces. BUT...
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It turns out that we still see them even in juvenile sauropods where the arch and centrum are unfused! And furthermore that the neural canal ridges are above the neurocentral joint, so the positioning isn’t quite right.
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What was our next idea...?? Stay tuned for more soon!
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#vertebrae #development #sauropod #paleontology #fossil #alamosaurus #rapetosaurus #anatomy #science #svpca2019 @mathew.wedel

Part 2 of Atterholt and Wedel, SVPCA 2019. (My Instagram “presenting” of a talk I recently gave at a paleontology conference.)
.
In my last post I shared that my coauthor and I discovered weird bony ridges in the neural canals of sauropods. Our next task was to figure out what they are!
.
Our first idea was that they might form at neurocentral joints. What the heck does that mean?? Well, in early development, all vertebrates (animals with a back bone) have vertebrae in two major pieces: the round centrum on the bottom (this forms the biggest joint between consecutive vertebrae) and the thin bony arch above it. They will ossify and fuse together as an animal grows. We thought neural canal ridges might be part of the suture between these two pieces. BUT...
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It turns out that we still see them even in juvenile sauropods where the arch and centrum are unfused! And furthermore that the neural canal ridges are above the neurocentral joint, so the positioning isn’t quite right.
.
What was our next idea...?? Stay tuned for more soon!
.
#vertebrae #development #sauropod #paleontology #fossil #alamosaurus #rapetosaurus #anatomy #science #svpca2019 @mathew.wedel

Last week I had the immense pleasure of attending the 67th Symposium of Vertebrate Paleontology and Comparative Anatomy. I gave a talk on some of my recent research, and thought it would be fun to also “present” my talk to a larger audience on Instagram.
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So here we go! This is Part 1 of Atterholt and Wedel, SVPCA 2019.
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The title of the talk mentions “osteological correlates,” meaning structures on bone that give us clues about soft tissue anatomy. In this case, we found bony things that tell us about neuroanatomy in dinosaurs...but we’ll get to that!
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Matt and I have noticed and documented bony ridges in the vertebral (neural) canals of many sauropod (long neck) dinosaurs. This is the space where the spinal cord sits. We only find them in the caudal (tail) vertebrae.
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They are very tiny and easy to overlook, but once you get the search image very easy to spot! We noticed that they are elongate from the front to back of the vertebra, but don’t extend all the way to the ends of the vertebral canal. They also are variable in size and position in the canal. .
So far, we have found these odd neural canal ridges in every neosauropod we’ve looked in! So they’re present in a great diversity of long-necked dinosaurs.
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The question then is: what are these?? Stay tuned for further posts on the various ideas we considered, and our final conclusion!
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#dinosaursofinstagram #dinosaur #research #svpca2019 #sauropod #vertebra #anatomy #paleontology @mathew.wedel

Last week I had the immense pleasure of attending the 67th Symposium of Vertebrate Paleontology and Comparative Anatomy. I gave a talk on some of my recent research, and thought it would be fun to also “present” my talk to a larger audience on Instagram.
.
So here we go! This is Part 1 of Atterholt and Wedel, SVPCA 2019.
.
The title of the talk mentions “osteological correlates,” meaning structures on bone that give us clues about soft tissue anatomy. In this case, we found bony things that tell us about neuroanatomy in dinosaurs...but we’ll get to that!
.
Matt and I have noticed and documented bony ridges in the vertebral (neural) canals of many sauropod (long neck) dinosaurs. This is the space where the spinal cord sits. We only find them in the caudal (tail) vertebrae.
.
They are very tiny and easy to overlook, but once you get the search image very easy to spot! We noticed that they are elongate from the front to back of the vertebra, but don’t extend all the way to the ends of the vertebral canal. They also are variable in size and position in the canal. .
So far, we have found these odd neural canal ridges in every neosauropod we’ve looked in! So they’re present in a great diversity of long-necked dinosaurs.
.
The question then is: what are these?? Stay tuned for further posts on the various ideas we considered, and our final conclusion!
.
#dinosaursofinstagram #dinosaur #research #svpca2019 #sauropod #vertebra #anatomy #paleontology @mathew.wedel

Super excited to share this recent addition to my mini museum! It was a purchase from @necromancehollywood a couple weeks ago when I was feeling little down and some retail therapy was in order. 😊 I HIGHLY recommend a visit there to anyone in the L.A. area. It is an amazing shop where you can get all kinds of anatomy goodies.
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The big guy here is the cannon bone of a giraffe! Next to it, for scale, is the cannon bone of a sheep. The cannon bone is characteristic of ungulates (hoofed mammals). Giraffes and sheep are both artiodactyls, or ungulates with an even number of toes; both have two on each foot. So in these guys, the cannon bone is formed from the fusion of the 3rd and 4th metacarpals or metatarsals depending on whether we’re talking about the fore- or hindfoot.
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Basically, this bone is a reeeeaaaally long hand (or foot) that short little toes (hooves) would attach to; first pic shows the end where this attachment occurs. Elongate foot bones and hooves are adaptations for agility and running fast that are seen in nearly all ungulates. What’s really striking here is how the giraffe and sheep cannon bones look nearly identical! Apart from size, that is.
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Last pic is one more to emphasize just how huge this giraffe bone is. It is the length of MY ENTIRE LEG, from hip to ankle (or rather, from greater trochanter to lateral malleolus 😉).
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#science #scicomm #bones #ungulate #ungulatesofinstagram #giraffe #sheep #anatomy #evolution

Super excited to share this recent addition to my mini museum! It was a purchase from @necromancehollywood a couple weeks ago when I was feeling little down and some retail therapy was in order. 😊 I HIGHLY recommend a visit there to anyone in the L.A. area. It is an amazing shop where you can get all kinds of anatomy goodies.
.
The big guy here is the cannon bone of a giraffe! Next to it, for scale, is the cannon bone of a sheep. The cannon bone is characteristic of ungulates (hoofed mammals). Giraffes and sheep are both artiodactyls, or ungulates with an even number of toes; both have two on each foot. So in these guys, the cannon bone is formed from the fusion of the 3rd and 4th metacarpals or metatarsals depending on whether we’re talking about the fore- or hindfoot.
.
Basically, this bone is a reeeeaaaally long hand (or foot) that short little toes (hooves) would attach to; first pic shows the end where this attachment occurs. Elongate foot bones and hooves are adaptations for agility and running fast that are seen in nearly all ungulates. What’s really striking here is how the giraffe and sheep cannon bones look nearly identical! Apart from size, that is.
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Last pic is one more to emphasize just how huge this giraffe bone is. It is the length of MY ENTIRE LEG, from hip to ankle (or rather, from greater trochanter to lateral malleolus 😉).
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#science #scicomm #bones #ungulate #ungulatesofinstagram #giraffe #sheep #anatomy #evolution

The first of two plastinated, hemisected pig heads I’ve had in the works for a while now. This one is for @westernuvetmed. Couldn’t be happier with how it turned out! Totally gorgeous. Second photo is the same head flipped over, all the hair and skin still intact. I had some trouble brushing out all the excess cured plastic, so it looks a little like it it has dandruff!
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#pig #pigsofinstagram #plastination #plastinationarts #anatomy #science #head #scienceart

The first of two plastinated, hemisected pig heads I’ve had in the works for a while now. This one is for @westernuvetmed. Couldn’t be happier with how it turned out! Totally gorgeous. Second photo is the same head flipped over, all the hair and skin still intact. I had some trouble brushing out all the excess cured plastic, so it looks a little like it it has dandruff!
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#pig #pigsofinstagram #plastination #plastinationarts #anatomy #science #head #scienceart

Here is that sacred ibis skull again, this time photographed in ventral view (in other words, from underneath). The lower jaw has been removed so we’re looking at the bottom of the top part of the skull.
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I’ve color-coded four bones that play an important role when a bird wants to swallow food: the quadrate, pterygoid, jugal, and palatine (swipe for labeled version).
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You’ve probably noticed that modern birds don’t have teeth. This is because teeth are very dense and heavy, and so are the robust jaw bones that support them. Birds have been able to lighten their skull by evolving toothless jaws and shifting the role of “chewing” to a special, rock-filled part of their stomach called the gizzard. Yep, that means their stomach will now be heavier, but it’s a lot closer to the bird’s center of mass than the head, so it’s still better for flight.
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ANYWAY, birds basically have to swallow their food whole, or at least in really large chunks. And now we get to the four colored bones in this image: the joints between all of them are still mobile, and can be pulled up by the jaw muscles so the bird can more easily swallow food whole! Pretty cool, right?! In contrast, the different bones in our skull are very tightly fused and don’t really move much at all (unless you’re the patient of a doctor of osteopathic medicine...but that’s a fun story for another time!).
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#birds #science #skull #anatomy #evolution #bones #ibis #macabre #scienceart #toothless #bird

Here is that sacred ibis skull again, this time photographed in ventral view (in other words, from underneath). The lower jaw has been removed so we’re looking at the bottom of the top part of the skull.
.
I’ve color-coded four bones that play an important role when a bird wants to swallow food: the quadrate, pterygoid, jugal, and palatine (swipe for labeled version).
.
You’ve probably noticed that modern birds don’t have teeth. This is because teeth are very dense and heavy, and so are the robust jaw bones that support them. Birds have been able to lighten their skull by evolving toothless jaws and shifting the role of “chewing” to a special, rock-filled part of their stomach called the gizzard. Yep, that means their stomach will now be heavier, but it’s a lot closer to the bird’s center of mass than the head, so it’s still better for flight.
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ANYWAY, birds basically have to swallow their food whole, or at least in really large chunks. And now we get to the four colored bones in this image: the joints between all of them are still mobile, and can be pulled up by the jaw muscles so the bird can more easily swallow food whole! Pretty cool, right?! In contrast, the different bones in our skull are very tightly fused and don’t really move much at all (unless you’re the patient of a doctor of osteopathic medicine...but that’s a fun story for another time!).
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#birds #science #skull #anatomy #evolution #bones #ibis #macabre #scienceart #toothless #bird

I’ve been on Instagram hiatus due to teaching commitments, but today was our last lab, so I had a moment to think about something other than human anatomy.
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This is a new addition to my collection: the skull of a sacred ibis. They are native to much of Africa, and live in large colonies near marshy wetlands where they feed on things like frogs, crabs, and insects.
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They are fairly large birds; this skull is about 10” long. Bird skulls tend to be very minimalistic with super thin bone in most places, but this one is big enough to be fairly substantial. And that makes it easy to identify anatomical structures!
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All vertebrate skulls are composed of many bones that are fused to a greater or lesser degree. Birds are definitely a case of the former. Most of the bones are so completely fused that we can no longer distinguish where one ends and the other begins. Swipe for a labeled photo of the skull, showing some familiar structures and a few of the individual bones that are still distinguishable.
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#science #anatomy #bird #skull #skullart #ibis #bones #birdsofinstagram #sacredibis

I’ve been on Instagram hiatus due to teaching commitments, but today was our last lab, so I had a moment to think about something other than human anatomy.
.
This is a new addition to my collection: the skull of a sacred ibis. They are native to much of Africa, and live in large colonies near marshy wetlands where they feed on things like frogs, crabs, and insects.
.
They are fairly large birds; this skull is about 10” long. Bird skulls tend to be very minimalistic with super thin bone in most places, but this one is big enough to be fairly substantial. And that makes it easy to identify anatomical structures!
.
All vertebrate skulls are composed of many bones that are fused to a greater or lesser degree. Birds are definitely a case of the former. Most of the bones are so completely fused that we can no longer distinguish where one ends and the other begins. Swipe for a labeled photo of the skull, showing some familiar structures and a few of the individual bones that are still distinguishable.
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#science #anatomy #bird #skull #skullart #ibis #bones #birdsofinstagram #sacredibis

#throwbackthursday to my first ever skeletonization project. I’m 11 years old here, doing some work as a volunteer paleontologist for @anzaborregodesertsp. This coyote was a roadkill donation that needed to be skeletonized for the comparative anatomy collection (bones of modern animals used to help identify fossil bones). .
I helped to skin and gut this guy, and then we boiled the bones to get rid of remaining soft tissue. In the photo I’m stirring the pot and checking the progress of the boiling skeleton! .
I was totally enamored and delighted with the experience. I remember that the thyroid cartilage (at the top of the stack of tracheal rings) survived the boiling process, and I discovered it fit perfectly on one of my fingers! So I proudly wore my cartilage ring every time I was in Anza Borrego, until I grew out of it. 😂
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#science #womeninstem #womeninscience #coyote #skeleton #grossbutcool #nerdandproud #deadstuff #roadkill

#throwbackthursday to my first ever skeletonization project. I’m 11 years old here, doing some work as a volunteer paleontologist for @anzaborregodesertsp. This coyote was a roadkill donation that needed to be skeletonized for the comparative anatomy collection (bones of modern animals used to help identify fossil bones). .
I helped to skin and gut this guy, and then we boiled the bones to get rid of remaining soft tissue. In the photo I’m stirring the pot and checking the progress of the boiling skeleton! .
I was totally enamored and delighted with the experience. I remember that the thyroid cartilage (at the top of the stack of tracheal rings) survived the boiling process, and I discovered it fit perfectly on one of my fingers! So I proudly wore my cartilage ring every time I was in Anza Borrego, until I grew out of it. 😂
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#science #womeninstem #womeninscience #coyote #skeleton #grossbutcool #nerdandproud #deadstuff #roadkill

It occurred to me when I was staring at this photo while editing that this looks rather looks like a super creepy dismembered monster hand. Can you picture a creature with hands like this?? 😆
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But actually, it’s another of my plastinated bird foot series. Still pretty cool though, right? This one is from a brown pelican! It’s quite large. This specimen is nearly the size of my wrist and hand. Anatomical details coming soon!
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Illustrations from the gorgeous “The Illustrated Bird” by Katrina Van Grouw. Love this book so much! I highly recommend it to anyone with an interest in birds, natural history, or science art.
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#science #scienceart #macabre #bird #tattooart #pelican #birdanatomy #womeninscience #foot #naturalhistory

It occurred to me when I was staring at this photo while editing that this looks rather looks like a super creepy dismembered monster hand. Can you picture a creature with hands like this?? 😆
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But actually, it’s another of my plastinated bird foot series. Still pretty cool though, right? This one is from a brown pelican! It’s quite large. This specimen is nearly the size of my wrist and hand. Anatomical details coming soon!
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Illustrations from the gorgeous “The Illustrated Bird” by Katrina Van Grouw. Love this book so much! I highly recommend it to anyone with an interest in birds, natural history, or science art.
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#science #scienceart #macabre #bird #tattooart #pelican #birdanatomy #womeninscience #foot #naturalhistory

Hi, friends! Here’s a pretty CT scan of a juvenile barn owl. 😊
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But today I’m here to spread the word about an awesome science event coming up! On April 13 the @westernsciencecenter in Hemet, CA will be hosting the Inland Empire Science Festival! This wonderful celebration of science promises to be full of super cool things to see, in addition to the regular museum exhibits.
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I’m extra excited because I’ll be there hosting the Lady Anatomica’s Pop-Up Comparative Anatomy Museum!! So if you’ve ever wanted to see (and touch!) some of the stuff I post about, come out to #IESF2019!
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#science #festival #outreach #popupmuseum #bones #plastination #scienceart #womeninstem

Hi, friends! Here’s a pretty CT scan of a juvenile barn owl. 😊
.
But today I’m here to spread the word about an awesome science event coming up! On April 13 the @westernsciencecenter in Hemet, CA will be hosting the Inland Empire Science Festival! This wonderful celebration of science promises to be full of super cool things to see, in addition to the regular museum exhibits.
.
I’m extra excited because I’ll be there hosting the Lady Anatomica’s Pop-Up Comparative Anatomy Museum!! So if you’ve ever wanted to see (and touch!) some of the stuff I post about, come out to #IESF2019!
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#science #festival #outreach #popupmuseum #bones #plastination #scienceart #womeninstem

Hi, friends! Today I want to share some exciting news: I’m officially an ambassador for the peer-review science journal @peerj_journals! I was inspired to volunteer for the position after publishing with them last year. PeerJ takes a process (scientific publication) that is often incredibly onerous and cumbersome and makes it unbelievably fast and easy. I was SUPER impressed! And now I’m excited to help spread the word about this journal to my fellow scientists.
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BUT, I’m also excited to tell non-scientists about PeerJ, too. It’s one of a growing number of journals that are #openaccess. That means ANYONE can download articles FOR FREE! You don’t have to pay a ridiculous amount of money for a single article, or for a subscription with the journal. Why is this important? It makes science accessible to anyone who is interested, and not just a handful of elite few in the ivory tower.
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Stay tuned for news about cool new articles coming out in PeerJ! Also, here’s a video of a cute little iguana skull that I have. 😊
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#peerj #science #research #iguana #skull #scicomm #womeninstem #publication #free #freeforeveryone

Hi, friends! Today I want to share some exciting news: I’m officially an ambassador for the peer-review science journal @peerj_journals! I was inspired to volunteer for the position after publishing with them last year. PeerJ takes a process (scientific publication) that is often incredibly onerous and cumbersome and makes it unbelievably fast and easy. I was SUPER impressed! And now I’m excited to help spread the word about this journal to my fellow scientists.
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BUT, I’m also excited to tell non-scientists about PeerJ, too. It’s one of a growing number of journals that are #openaccess. That means ANYONE can download articles FOR FREE! You don’t have to pay a ridiculous amount of money for a single article, or for a subscription with the journal. Why is this important? It makes science accessible to anyone who is interested, and not just a handful of elite few in the ivory tower.
.
Stay tuned for news about cool new articles coming out in PeerJ! Also, here’s a video of a cute little iguana skull that I have. 😊
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#peerj #science #research #iguana #skull #scicomm #womeninstem #publication #free #freeforeveryone

Here’s another little treasure from my visit to the Natural History Museum of L.A. County a few months ago. It’s part of the skull of one of my favorite animals: Cryptobranchus, aka the hellbender salamander! .
These guys are humongo salamanders that live in freshwater of the northeastern U.S. This partial skull alone nearly filled the space in my palm! They really creep me out but also totally fascinate me.
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First pic is ventral (bottom) view. The anterior (forward) part of the skull is pointing down. One standout characteristic is the double row of sharp little teeth. It may seem super weird, but actually lots of amphibians and fish have double rows of teeth, and sometimes teeth on the palate to boot!
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Second photo is the dorsal (top) side of the head. The two nostrils are visible at the tip of the nose, and the large indentations are part of the orbit, where the eyes sit.
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#science #salamander #giantsalamander #womeninstem #skull #creepy #cool #scicomm #teeth #anatomy #bones

Here’s another little treasure from my visit to the Natural History Museum of L.A. County a few months ago. It’s part of the skull of one of my favorite animals: Cryptobranchus, aka the hellbender salamander! .
These guys are humongo salamanders that live in freshwater of the northeastern U.S. This partial skull alone nearly filled the space in my palm! They really creep me out but also totally fascinate me.
.
First pic is ventral (bottom) view. The anterior (forward) part of the skull is pointing down. One standout characteristic is the double row of sharp little teeth. It may seem super weird, but actually lots of amphibians and fish have double rows of teeth, and sometimes teeth on the palate to boot!
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Second photo is the dorsal (top) side of the head. The two nostrils are visible at the tip of the nose, and the large indentations are part of the orbit, where the eyes sit.
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#science #salamander #giantsalamander #womeninstem #skull #creepy #cool #scicomm #teeth #anatomy #bones

For your viewing pleasure, a plastinated pelican lung.
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First image is lateral view (towards the outer side of the body), second is medial (towards the midline). The top/dorsal side of the lung is the edge with several deep indentations (left in the fist pic). What are those incisures?? Those indentations are from the ribs of the animal, because bird lungs are very tightly pressed up against them. Weird, right??
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You may be wondering how the lungs can move to expand and contract as the bird breaths if they are stuck to the ribs. The answer: they don’t! Bird lungs are rigid; they don’t expand and contract as the animal breaths. This means that air only flows one way through the lungs, not in and out like us.
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In birds, air enters the main bronchus via the trachea/windpipe (just like us) BUT it then passes to an elaborate system of membranous air sacs at the back of the body (not at all like us!). From there, it moves through the lungs, then to anterior air sacs, then out of the body. This is called unidirectional flow, and is a super efficient way of breathing if you’re often engaged in the highly aerobic activity of flying.
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#bird #pelican #lung #anatomy #science #womeninstem #plastination

For your viewing pleasure, a plastinated pelican lung.
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First image is lateral view (towards the outer side of the body), second is medial (towards the midline). The top/dorsal side of the lung is the edge with several deep indentations (left in the fist pic). What are those incisures?? Those indentations are from the ribs of the animal, because bird lungs are very tightly pressed up against them. Weird, right??
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You may be wondering how the lungs can move to expand and contract as the bird breaths if they are stuck to the ribs. The answer: they don’t! Bird lungs are rigid; they don’t expand and contract as the animal breaths. This means that air only flows one way through the lungs, not in and out like us.
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In birds, air enters the main bronchus via the trachea/windpipe (just like us) BUT it then passes to an elaborate system of membranous air sacs at the back of the body (not at all like us!). From there, it moves through the lungs, then to anterior air sacs, then out of the body. This is called unidirectional flow, and is a super efficient way of breathing if you’re often engaged in the highly aerobic activity of flying.
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#bird #pelican #lung #anatomy #science #womeninstem #plastination

Isn’t this simple and lovely? It’s a close-up of the ventral (bottom) view of vertebrae from a white-throated monitor lizard. They’re still connected because some of the ligaments that hold them together are still there. Our skeletons are held together by LOTS of important connective tissues like ligaments, which are so tough that they can often withstand the process of decay.
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Here you see an example of one if my favorite ligaments: the anterior longitudinal ligament, which runs continuously down this surface of aaallll the vertebrae. There’s also a matching posterior longitudinal ligament on the other side of the vertebral bodies (not shown here)!
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#science #anatomy #monitorlizard #reptilesofinstagram #womeninstem #ligaments #vertebrae #bones #skeleton

Isn’t this simple and lovely? It’s a close-up of the ventral (bottom) view of vertebrae from a white-throated monitor lizard. They’re still connected because some of the ligaments that hold them together are still there. Our skeletons are held together by LOTS of important connective tissues like ligaments, which are so tough that they can often withstand the process of decay.
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Here you see an example of one if my favorite ligaments: the anterior longitudinal ligament, which runs continuously down this surface of aaallll the vertebrae. There’s also a matching posterior longitudinal ligament on the other side of the vertebral bodies (not shown here)!
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#science #anatomy #monitorlizard #reptilesofinstagram #womeninstem #ligaments #vertebrae #bones #skeleton

By now you probably know that I’m a sucker for pretty things. That’s why, as a paleonhistologist I am always drawn to photos of bone under crossed-nicols. It’s a way of manipulating light under a microscope that gives these GORGEOUS colors, caused by different components of the tissue arranged in different orientations.
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This is a sneak peak into one of my current research projects. It’s a slide of fossilized bone that I made by cutting a super thin slice and grinding it thin enough for light to pass through. Here, you see the tissue at 400x actual size.
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There are lots of cool features to see here. All of the small, black dots are osteocyte lacunae; they are where the bone cells “live.” You can also see four osteons. These are concentric layers of osteocytes around a central vascular canal (the larger black circles, where blood vessels were located). Swipe for a labeled pic to help you spot the cool stuff!
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The presence of these osteons and holes for blood vessels tells us that this particular bone, from a Late Cretaceous bird, was growing quickly when it died!
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#science #womeninstem #scienceart #artandscience #histology #bone #osteon #fossil #scicomm #research #cells #beautiful

By now you probably know that I’m a sucker for pretty things. That’s why, as a paleonhistologist I am always drawn to photos of bone under crossed-nicols. It’s a way of manipulating light under a microscope that gives these GORGEOUS colors, caused by different components of the tissue arranged in different orientations.
.
This is a sneak peak into one of my current research projects. It’s a slide of fossilized bone that I made by cutting a super thin slice and grinding it thin enough for light to pass through. Here, you see the tissue at 400x actual size.
.
There are lots of cool features to see here. All of the small, black dots are osteocyte lacunae; they are where the bone cells “live.” You can also see four osteons. These are concentric layers of osteocytes around a central vascular canal (the larger black circles, where blood vessels were located). Swipe for a labeled pic to help you spot the cool stuff!
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The presence of these osteons and holes for blood vessels tells us that this particular bone, from a Late Cretaceous bird, was growing quickly when it died!
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#science #womeninstem #scienceart #artandscience #histology #bone #osteon #fossil #scicomm #research #cells #beautiful

Here’s a beautiful little caudal (tail) vertebra from the skeleton of a green iguana in the herpetology collection at the Natural History Museum of Los Angeles @nhmla (I visited a couple months ago for research purposes).
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This specimen is a lovely example of the two vertebral arches found on the tail verts of most reptiles: the neural arch (on top) and the hemal arch (on bottom). Swipe for a labeled photo. 🙂
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The neural arch is where the spinal cord passes through. Every vertebrate—including us!—has neural arches in the vertebrae that house the spinal cord.
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The hemal arch is where blood vessels run through. In reptiles with looong tails, some extra support is needed for large vessels like the aorta in order to get blood supply all the way out to the end of the tail. Guess who else has awesome hemal arches?? DINOSAURS. Look for them on the tail of the next dino skeleton you see!
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#science #anatomy #anatomyart #bone #vertebrae #caudal #tail #iguana #womeninstem #scicomm #reptile #reptilesofinstagram

Here’s a beautiful little caudal (tail) vertebra from the skeleton of a green iguana in the herpetology collection at the Natural History Museum of Los Angeles @nhmla (I visited a couple months ago for research purposes).
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This specimen is a lovely example of the two vertebral arches found on the tail verts of most reptiles: the neural arch (on top) and the hemal arch (on bottom). Swipe for a labeled photo. 🙂
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The neural arch is where the spinal cord passes through. Every vertebrate—including us!—has neural arches in the vertebrae that house the spinal cord.
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The hemal arch is where blood vessels run through. In reptiles with looong tails, some extra support is needed for large vessels like the aorta in order to get blood supply all the way out to the end of the tail. Guess who else has awesome hemal arches?? DINOSAURS. Look for them on the tail of the next dino skeleton you see!
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#science #anatomy #anatomyart #bone #vertebrae #caudal #tail #iguana #womeninstem #scicomm #reptile #reptilesofinstagram

More of that hemisected pig head. 😄 This is a close-up of the inside of the nose. That broad, white tissue is cartilage forming the nasal septum. What’s really special here is that you can see all the tiny blood vessels supplying blood to the cartilage! Because the head was frozen when we cut it, the blood didn’t immediately leak out. It’s soooo beautiful!!
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#science #macabreart #pigsofinstagram #womeninstem #dissection #nose #pig #anatomy #vetmed #teachersofinstagram #scienceart #cartilage #scicomm

More of that hemisected pig head. 😄 This is a close-up of the inside of the nose. That broad, white tissue is cartilage forming the nasal septum. What’s really special here is that you can see all the tiny blood vessels supplying blood to the cartilage! Because the head was frozen when we cut it, the blood didn’t immediately leak out. It’s soooo beautiful!!
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#science #macabreart #pigsofinstagram #womeninstem #dissection #nose #pig #anatomy #vetmed #teachersofinstagram #scienceart #cartilage #scicomm

My latest anatomy project has been this lovely pig head. I bisected it while it was frozen and now I will plastinate one half and skeletonize the other. Huge thanks to @mathew.wedel for taking this picture and help processing the specimen! He has chronicled our adventures with this #piggie at SVPOW.com. Thanks, also, to @westernuvetmed for letting me use your band saw and giving me a place to dissect. I have the best colleagues! 😊
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This pig head had been cut mid-sagitally; basically, I made one long cut right down the middle. This photo was taken right after cutting it. Everything is still fresh. I’m super glad we got this documented, cause the brain and spinal cord have since turned to mush and fallen out. 🙁 But the rest of this soft tissue will eventually be preserved forever through plastination! 😄
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Swipe for this same image with different anatomical parts labeled. Pig anatomy is actually super similar to ours in lots of ways. Everything I labeled we have too! Just in slightly different relative shapes and sizes. Enjoy!!! .
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#science #anatomy #vetmed #pig #pigsofinstagram #womeninstem #dissection #macabreart #scienceart #piggy #teachersofinstagram #brain #tongue #head

My latest anatomy project has been this lovely pig head. I bisected it while it was frozen and now I will plastinate one half and skeletonize the other. Huge thanks to @mathew.wedel for taking this picture and help processing the specimen! He has chronicled our adventures with this #piggie at SVPOW.com. Thanks, also, to @westernuvetmed for letting me use your band saw and giving me a place to dissect. I have the best colleagues! 😊
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This pig head had been cut mid-sagitally; basically, I made one long cut right down the middle. This photo was taken right after cutting it. Everything is still fresh. I’m super glad we got this documented, cause the brain and spinal cord have since turned to mush and fallen out. 🙁 But the rest of this soft tissue will eventually be preserved forever through plastination! 😄
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Swipe for this same image with different anatomical parts labeled. Pig anatomy is actually super similar to ours in lots of ways. Everything I labeled we have too! Just in slightly different relative shapes and sizes. Enjoy!!! .
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#science #anatomy #vetmed #pig #pigsofinstagram #womeninstem #dissection #macabreart #scienceart #piggy #teachersofinstagram #brain #tongue #head

Okay, time to share some photos of the actual fossil! I present to you the furcula (#wishbone), ulna (a forearm bone), and sternum (#breastbone) of Mirarce eatoni.
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Mirarce is 75 million years old, and comes from rocks in Utah. It is an enantiornithine bird, belonging to a group that is like cousins to modern birds. This fossil is special because it tells a cool evolutionary story. Mirarce shows us that by the Late Cretaceous, some enantiornithine birds had evolved adaptations for strong, sophisticated flight INDEPENDENTLY from modern birds! That means both groups evolve them separately.
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The first evidence of this is the wish bone. In early enantiornithines, this bone is wider and U-shaped. In Mirarce, it is narrower and V-shaped, like living birds. This way it works as a better spring to support the action of flight muscles.
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Second, the ulna has very large, bumpy patches of bone, which are probably quill knobs. In modern birds, quill knobs are places where flight feathers attach to the bone to reinforce them during flight (for comparison you can see the quill knobs of a modern pelican below the fossil). Mirarce is the very first enantiornithine with quill knobs!
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Third, the breast bone of early enantiornithines has a low keel, meaning their flight muscles were smallish (though the could still fly). We only have the end piece of Mirarce’s sternum, but it seems to have had a deeper keel for much larger flight muscles—again, like living birds.
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See if you can find the furcula and sternum on your Thanksgiving turkey next week! 😄
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#fossil #bird #womeninstem #science #bone #evolution #flight #cretaceous #evolutionofflight #enantiornithine #mirarce

Okay, time to share some photos of the actual fossil! I present to you the furcula (#wishbone), ulna (a forearm bone), and sternum (#breastbone) of Mirarce eatoni.
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Mirarce is 75 million years old, and comes from rocks in Utah. It is an enantiornithine bird, belonging to a group that is like cousins to modern birds. This fossil is special because it tells a cool evolutionary story. Mirarce shows us that by the Late Cretaceous, some enantiornithine birds had evolved adaptations for strong, sophisticated flight INDEPENDENTLY from modern birds! That means both groups evolve them separately.
.
The first evidence of this is the wish bone. In early enantiornithines, this bone is wider and U-shaped. In Mirarce, it is narrower and V-shaped, like living birds. This way it works as a better spring to support the action of flight muscles.
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Second, the ulna has very large, bumpy patches of bone, which are probably quill knobs. In modern birds, quill knobs are places where flight feathers attach to the bone to reinforce them during flight (for comparison you can see the quill knobs of a modern pelican below the fossil). Mirarce is the very first enantiornithine with quill knobs!
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Third, the breast bone of early enantiornithines has a low keel, meaning their flight muscles were smallish (though the could still fly). We only have the end piece of Mirarce’s sternum, but it seems to have had a deeper keel for much larger flight muscles—again, like living birds.
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See if you can find the furcula and sternum on your Thanksgiving turkey next week! 😄
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#fossil #bird #womeninstem #science #bone #evolution #flight #cretaceous #evolutionofflight #enantiornithine #mirarce

More about Mirarce! This is a skeletal reconstruction of the extinct Cretaceous bird from Utah that I published on today with my colleagues Howard Hutchison and Jingmai O’Connor. I have the talented Scott Hartman to thank for this illustration (skeletaldrawing.com).
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The white bits are parts that were found. We have about 30% of the skeleton! It may not sound like a lot, but it’s WAY more than any other North American enantiornithine bird (most of which are known from a single foot bone). Now we have much more information about the anatomy and evolution of this group! More details in another post soon...
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But for now, let’s talk about the name: Mirarce eatoni (Meer-ark-ee). One of the most fun parts of describing a new fossil is coming up with the name! It’s a chance to get creative, and I have @andrewmcdonald1701 to thank for help coming up with this one.
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Mirus = “wonderful” in Latin, paying homage to the exquisite 3d preservation of the fossil. Arce = name of the winged messenger of the titans in Greek mythology, highlighting the advanced flight adaptations of this bird. Eatoni = in honor of Dr. Jeff Eaton for his years of important research on Cretaceous fossils from Utah.
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#bird #science #womeninstem #bone #extinct #scotthartman #skeleton

More about Mirarce! This is a skeletal reconstruction of the extinct Cretaceous bird from Utah that I published on today with my colleagues Howard Hutchison and Jingmai O’Connor. I have the talented Scott Hartman to thank for this illustration (skeletaldrawing.com).
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The white bits are parts that were found. We have about 30% of the skeleton! It may not sound like a lot, but it’s WAY more than any other North American enantiornithine bird (most of which are known from a single foot bone). Now we have much more information about the anatomy and evolution of this group! More details in another post soon...
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But for now, let’s talk about the name: Mirarce eatoni (Meer-ark-ee). One of the most fun parts of describing a new fossil is coming up with the name! It’s a chance to get creative, and I have @andrewmcdonald1701 to thank for help coming up with this one.
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Mirus = “wonderful” in Latin, paying homage to the exquisite 3d preservation of the fossil. Arce = name of the winged messenger of the titans in Greek mythology, highlighting the advanced flight adaptations of this bird. Eatoni = in honor of Dr. Jeff Eaton for his years of important research on Cretaceous fossils from Utah.
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#bird #science #womeninstem #bone #extinct #scotthartman #skeleton

Hello, World. Today it is my great pleasure to introduce you to Mirarce eatoni.
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This morning my colleagues and I published a paper naming a new genus and species of extinct bird, and describing the anatomy of this beautiful and important fossil.
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It was found by my collaborator Howard Hutchison in Grand Staircase Escalante National Monument in Utah, from Late Cretaceous rocks (75 million years old). It is one of the biggest and by far the most complete bird belonging to an extinct group called Enantiornithes!
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Here you see a drop-dead gorgeous living illustration of Mirarce by award-winning paleoartist Brian Engh (dontmesswithdinosaurs.com). He took inspiration from pictures of storks perched on water buffalo heads. 😊 Mirarce is perched on the horns of Utahceratops gettyi, a ceratopsian dino found in the same rocks. (Though we don’t know that it actually did this—but I gave him creative freedom as an artist.)
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Oh yeah, and Mirarce is getting featured on a number of blogs and news outlets, including an article on the National Geographic website! Keep your eyes open for Mirarce sightings today!
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#paleontology #fossil #bird #evolution #cretaceous #peerj #mirarce #science #utah #kaiparowits #womeninscience #scicomm

Hello, World. Today it is my great pleasure to introduce you to Mirarce eatoni.
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This morning my colleagues and I published a paper naming a new genus and species of extinct bird, and describing the anatomy of this beautiful and important fossil.
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It was found by my collaborator Howard Hutchison in Grand Staircase Escalante National Monument in Utah, from Late Cretaceous rocks (75 million years old). It is one of the biggest and by far the most complete bird belonging to an extinct group called Enantiornithes!
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Here you see a drop-dead gorgeous living illustration of Mirarce by award-winning paleoartist Brian Engh (dontmesswithdinosaurs.com). He took inspiration from pictures of storks perched on water buffalo heads. 😊 Mirarce is perched on the horns of Utahceratops gettyi, a ceratopsian dino found in the same rocks. (Though we don’t know that it actually did this—but I gave him creative freedom as an artist.)
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Oh yeah, and Mirarce is getting featured on a number of blogs and news outlets, including an article on the National Geographic website! Keep your eyes open for Mirarce sightings today!
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#paleontology #fossil #bird #evolution #cretaceous #peerj #mirarce #science #utah #kaiparowits #womeninscience #scicomm

Rattlesnake heart, anyone?? Yep, that boring beige blob in the center of the first photo is the heart of a 6 foot long Mojave green rattler. (Turns out this specimen doesn’t photograph too well—haha.)
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Snakes have pretty typical reptilian hearts. They are three-chambered, with two atria at the top of the heart and one large ventricle underneath them. In contrast, mammal and bird hearts have four chambers.
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This specimen is too small to distinguish separate chambers from the outside, but you can distinguish the body of the heart itself from the mass of blood vessels leaving it (swipe for a labeled photo). There are two large aortas branching off to the right and left to carry oxygenated blood to the rest of the body, and two pulmonary arteries bringing deoxygenated blood to the lung (just one in snakes!) to pick up oxygen, plus other smaller veins bringing blood back to the heart.
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#science #anatomy #snake #snek #heart #plastination #macabreart #macabre #womeninstem #reptile

Rattlesnake heart, anyone?? Yep, that boring beige blob in the center of the first photo is the heart of a 6 foot long Mojave green rattler. (Turns out this specimen doesn’t photograph too well—haha.)
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Snakes have pretty typical reptilian hearts. They are three-chambered, with two atria at the top of the heart and one large ventricle underneath them. In contrast, mammal and bird hearts have four chambers.
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This specimen is too small to distinguish separate chambers from the outside, but you can distinguish the body of the heart itself from the mass of blood vessels leaving it (swipe for a labeled photo). There are two large aortas branching off to the right and left to carry oxygenated blood to the rest of the body, and two pulmonary arteries bringing deoxygenated blood to the lung (just one in snakes!) to pick up oxygen, plus other smaller veins bringing blood back to the heart.
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#science #anatomy #snake #snek #heart #plastination #macabreart #macabre #womeninstem #reptile

Last week I got to attend the awesome Society of Vertebrate Paleontology conference in Albuquerque (so fun and so exhausting) but now I’m back to share more weird facts about birds and the air inside of them!
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Lately I’ve been posting about bizarre branches of the air sac system at actually enter the neural canal and contact the spinal cord. If you’re wondering how they get in there in the first place, read on!
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This is a diagram I made showing the small air sac branches around the OUTSIDE of a vertebra. The bone you see here is a neck (cervical) vertebra from an ostrich.
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There are two paired tubes of air that run along the side of the neck, which often go into the vertebrae at joints in between them. They also sometimes merge with other air-filled pockets on TOP of the vertebrae. These, too, sometimes bleb into the vertebral canal where the spinal cord is.
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Basically, there is an amorphous blob of air-filled membrane wrapped around the outside of these bones, and often also going inside of them. Fun fact for the day!
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#science #womeninstem #ostrich #bird #cervical #anatomy #livingdinosaur #teachersofinstagram #scicomm #oddity #bone #bones

Last week I got to attend the awesome Society of Vertebrate Paleontology conference in Albuquerque (so fun and so exhausting) but now I’m back to share more weird facts about birds and the air inside of them!
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Lately I’ve been posting about bizarre branches of the air sac system at actually enter the neural canal and contact the spinal cord. If you’re wondering how they get in there in the first place, read on!
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This is a diagram I made showing the small air sac branches around the OUTSIDE of a vertebra. The bone you see here is a neck (cervical) vertebra from an ostrich.
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There are two paired tubes of air that run along the side of the neck, which often go into the vertebrae at joints in between them. They also sometimes merge with other air-filled pockets on TOP of the vertebrae. These, too, sometimes bleb into the vertebral canal where the spinal cord is.
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Basically, there is an amorphous blob of air-filled membrane wrapped around the outside of these bones, and often also going inside of them. Fun fact for the day!
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#science #womeninstem #ostrich #bird #cervical #anatomy #livingdinosaur #teachersofinstagram #scicomm #oddity #bone #bones

Hi, everyone! This is going to be the second in a series of posts about weird air-filled structures in birds. 😄
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Anyone who has talked science with me lately knows I’ve been having a research-obsession with something called supramedullary airways (yeah, it’s a mouthful!). My friend Matt Wedel got me hooked on this very niche but very interesting aspect of bird anatomy. Check out his blog for more info about our recent research: svpow.com!
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Birds need lots of oxygen to fly, but their lungs are actually super small. BUT, they are connected to an elaborate system of air sacs, basically balloons of all shapes and sizes found throughout the body—under the skin, between muscles, in body cavities, and INSIDE of bone.
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Sometimes branches of these air sacs go inside of the vertebral canal and contact the spinal cord! These are called supramedullary airways.
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They come in all shapes and sizes in different birds. In my last post you saw them in a pelican. This is what they look like in an ostrich. (Colors in second pic: yellow - bony vertebral canal, magenta - spinal cord, teal - supramedullary airways.)
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Some birds have them, some don’t. Sometimes they are big, sometimes they are tiny. Right now we’re documenting the variation seen in many types of birds and are super excited by all the weird differences! You can see in the ostrich the airways are present as three tubes on top of the spinal cord. They don’t fully encase it like in the pelican. More to come soon!
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#bird #ostrich #ctscan #comparativeanatomy #birdanatomy #science #scicomm #livingdinosaur #womeninstem #niche #anatomy

Hi, everyone! This is going to be the second in a series of posts about weird air-filled structures in birds. 😄
.
Anyone who has talked science with me lately knows I’ve been having a research-obsession with something called supramedullary airways (yeah, it’s a mouthful!). My friend Matt Wedel got me hooked on this very niche but very interesting aspect of bird anatomy. Check out his blog for more info about our recent research: svpow.com!
.
Birds need lots of oxygen to fly, but their lungs are actually super small. BUT, they are connected to an elaborate system of air sacs, basically balloons of all shapes and sizes found throughout the body—under the skin, between muscles, in body cavities, and INSIDE of bone.
.
Sometimes branches of these air sacs go inside of the vertebral canal and contact the spinal cord! These are called supramedullary airways.
.
They come in all shapes and sizes in different birds. In my last post you saw them in a pelican. This is what they look like in an ostrich. (Colors in second pic: yellow - bony vertebral canal, magenta - spinal cord, teal - supramedullary airways.)
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Some birds have them, some don’t. Sometimes they are big, sometimes they are tiny. Right now we’re documenting the variation seen in many types of birds and are super excited by all the weird differences! You can see in the ostrich the airways are present as three tubes on top of the spinal cord. They don’t fully encase it like in the pelican. More to come soon!
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#bird #ostrich #ctscan #comparativeanatomy #birdanatomy #science #scicomm #livingdinosaur #womeninstem #niche #anatomy

One of my favorite things about being an anatomist are those moments of “Wow, this animal is freaky!” when I see a weird morphology. Lately I’ve been doing a lot of work on bird CT scans studying one of those really weird features: in birds, the respiratory system enters the vertebral canal!
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You know the holes in your vertebrae that should just be full of your spinal cord? Well, in some birds there is air INSIDE of the vertebrae in contact with the spinal cord. These air spaces are part of the air sac system connected to the lungs (basically it’s like a bunch of balloons inside of birds, distributed throughout their bodies).
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Sometimes the air spaces in the vertebrae are absent or very small. And sometimes they are big and can even completely encase the spinal cord! That is so freaky. You can see an example in this CT scan of a brown pelican. The spinal cord is totally surrounded by air, and not in contact with bone at all. Color scheme in second image: yellow - vertebral canal, teal - air, magenta - spinal cord.
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Last month I got to present this research at the Society of Vertebrate Paleontology and Comparative Anatomy annual conference in Manchester, UK. It was soo much fun. The abstract and slides from the talk are available as a preprint on the PeerJ website (a scientific journal) if you search for my name. Yay for making science available to everyone!
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#bird #pelican #ctscan #deadstuff #anatomy #freaky #science #scicomm #livingdinosaur #openaccess #comparativeanatomy #svpca2018

One of my favorite things about being an anatomist are those moments of “Wow, this animal is freaky!” when I see a weird morphology. Lately I’ve been doing a lot of work on bird CT scans studying one of those really weird features: in birds, the respiratory system enters the vertebral canal!
.
You know the holes in your vertebrae that should just be full of your spinal cord? Well, in some birds there is air INSIDE of the vertebrae in contact with the spinal cord. These air spaces are part of the air sac system connected to the lungs (basically it’s like a bunch of balloons inside of birds, distributed throughout their bodies).
.
Sometimes the air spaces in the vertebrae are absent or very small. And sometimes they are big and can even completely encase the spinal cord! That is so freaky. You can see an example in this CT scan of a brown pelican. The spinal cord is totally surrounded by air, and not in contact with bone at all. Color scheme in second image: yellow - vertebral canal, teal - air, magenta - spinal cord.
.
Last month I got to present this research at the Society of Vertebrate Paleontology and Comparative Anatomy annual conference in Manchester, UK. It was soo much fun. The abstract and slides from the talk are available as a preprint on the PeerJ website (a scientific journal) if you search for my name. Yay for making science available to everyone!
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#bird #pelican #ctscan #deadstuff #anatomy #freaky #science #scicomm #livingdinosaur #openaccess #comparativeanatomy #svpca2018

This is a bit of a throwback, but I wanted to share a cool fossil I published on with some of my colleagues back in 2016. .
It’s the back end of a small bird, probably about the size of a scrub jay. You can see the legs, hip bones, and some special tail feathers in the first picture. This guy is from a site in Gansu Province, China, where the rocks have been dated at 124-120 million years old (Early Cretaceous).
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We named this lovely *Fetianius paradisia* after the beautiful murals of feitian (flying spirits) in the Mogao Caves close to the site, and after birds of paradise for their crazy tail feather displays.
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While perhaps not super impressive at first glance, this fossil actually tells a super cool story. The tail feathers are really special, because we found three different feather types (A, B, and C in the second photo). This is unusual—most other fossil birds from the Cretaceous just have one type. Furthermore (this is where it really gets weird), their shape indicates these feathers were not aerodynamic! In other words, they were an adaptation for sexual display! Such large, elaborate structures hint strongly that this is an example of sexual dimorphism in the fossil record. These feathers bear a resemblance to those of modern birds famous for sexual dimorphism and wild feather displays, such as the greater bird-of-paradise. Swipe for a comparative pic!
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For more info or to download the paper, check out my research blog: http://www.jessieatterholt.com/research-blog.
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#birdfossil #bird #fossil #birdsofparadise #feathers #cretaceous #sexualdimorphism #display #science #evolution #scicomm #womeninstem #paleontology

This is a bit of a throwback, but I wanted to share a cool fossil I published on with some of my colleagues back in 2016. .
It’s the back end of a small bird, probably about the size of a scrub jay. You can see the legs, hip bones, and some special tail feathers in the first picture. This guy is from a site in Gansu Province, China, where the rocks have been dated at 124-120 million years old (Early Cretaceous).
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We named this lovely *Fetianius paradisia* after the beautiful murals of feitian (flying spirits) in the Mogao Caves close to the site, and after birds of paradise for their crazy tail feather displays.
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While perhaps not super impressive at first glance, this fossil actually tells a super cool story. The tail feathers are really special, because we found three different feather types (A, B, and C in the second photo). This is unusual—most other fossil birds from the Cretaceous just have one type. Furthermore (this is where it really gets weird), their shape indicates these feathers were not aerodynamic! In other words, they were an adaptation for sexual display! Such large, elaborate structures hint strongly that this is an example of sexual dimorphism in the fossil record. These feathers bear a resemblance to those of modern birds famous for sexual dimorphism and wild feather displays, such as the greater bird-of-paradise. Swipe for a comparative pic!
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For more info or to download the paper, check out my research blog: http://www.jessieatterholt.com/research-blog.
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#birdfossil #bird #fossil #birdsofparadise #feathers #cretaceous #sexualdimorphism #display #science #evolution #scicomm #womeninstem #paleontology

Yesterday I had arts and crafts time at work, and it was SO much fun! As part of a collaboration with Dr. Matt Wedel I am helping to reconstruct vertebrae from Haplocanthosaurus, and type of sauropod dinosaur.
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First, we CT scanned a series of #caudal (tail) vertebrae. Next, we worked with our 3D visualization department, who made a 3D print of our best vert at 85% actual size. THEN Matt and I sculpted on the missing and broken parts (this was the really fun part!). .
Here you see the 3D print in grey, and our sculpted portions in baby pink. Now it will be scanned again, and our colleagues will digitally remove deformations. Ultimately we want to reconstruct the vertebrae both digitally and in 3D prints to help is understand the spinal cord anatomy of these animals. Technology is super cool!! .
Swipe for a pic of the sculpting process in action, and check out SVPOW for Matt’s blog post about the project!
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#science #scienceteacher #scienceart #technology #3dprinting #sauropod #haplocanthosaurus #vertebrae #dinosaur #scicomm #paleontology #ladyscientist #womeninstem

Yesterday I had arts and crafts time at work, and it was SO much fun! As part of a collaboration with Dr. Matt Wedel I am helping to reconstruct vertebrae from Haplocanthosaurus, and type of sauropod dinosaur.
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First, we CT scanned a series of #caudal (tail) vertebrae. Next, we worked with our 3D visualization department, who made a 3D print of our best vert at 85% actual size. THEN Matt and I sculpted on the missing and broken parts (this was the really fun part!). .
Here you see the 3D print in grey, and our sculpted portions in baby pink. Now it will be scanned again, and our colleagues will digitally remove deformations. Ultimately we want to reconstruct the vertebrae both digitally and in 3D prints to help is understand the spinal cord anatomy of these animals. Technology is super cool!! .
Swipe for a pic of the sculpting process in action, and check out SVPOW for Matt’s blog post about the project!
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#science #scienceteacher #scienceart #technology #3dprinting #sauropod #haplocanthosaurus #vertebrae #dinosaur #scicomm #paleontology #ladyscientist #womeninstem

I love this specimen, because it tells a super cool story...and it’s sooooo pretty! This is a cross-section through one of the #cervical (neck) vertebrae of an Apatosaurus. And here is the crazy thing: the black stuff is bone, but the white stuff is all pretty, white geodes! In other words, this huge bone from a massive animal is super thin-walled and was mostly just empty space in the living organism!!
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That might seem totally crazy, but this is actually very common among #dinosaurs, especially #sauropods like this guy and #theropods. This is because many of their skeletal elements are #pneumatic—they are filled with air, and were actually connected to the respiratory system. And what’s extra cool is that we see this exact same thing in #livingdinosaurs, AKA birds. 😁
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It might seem totally insane that birds evolved from dinosaurs, but this is one example of many surprising and awesome pieces of evidence paleontologists have discovered that support this relationship. Yay for fossils!!
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If you want to read more about skeletal pneumaticity, check out these cool articles by my friend and colleague Dr. Matt Wedel on his blog, SVPOW: https://svpow.com/2008/03/12/the-heart-of-the-matter/ AND https://svpow.com/2009/07/20/asp-target-of-opportunity/.
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#paleontology #paleontologist #dinosaur #sauropod #vertebra #fossil #evolution #coolscience #science #scienceart #teachersofinstagram #scicomm #womeninscience #ladyscientist #apatosaurus #pneumaticity

I love this specimen, because it tells a super cool story...and it’s sooooo pretty! This is a cross-section through one of the #cervical (neck) vertebrae of an Apatosaurus. And here is the crazy thing: the black stuff is bone, but the white stuff is all pretty, white geodes! In other words, this huge bone from a massive animal is super thin-walled and was mostly just empty space in the living organism!!
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That might seem totally crazy, but this is actually very common among #dinosaurs, especially #sauropods like this guy and #theropods. This is because many of their skeletal elements are #pneumatic—they are filled with air, and were actually connected to the respiratory system. And what’s extra cool is that we see this exact same thing in #livingdinosaurs, AKA birds. 😁
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It might seem totally insane that birds evolved from dinosaurs, but this is one example of many surprising and awesome pieces of evidence paleontologists have discovered that support this relationship. Yay for fossils!!
.
If you want to read more about skeletal pneumaticity, check out these cool articles by my friend and colleague Dr. Matt Wedel on his blog, SVPOW: https://svpow.com/2008/03/12/the-heart-of-the-matter/ AND https://svpow.com/2009/07/20/asp-target-of-opportunity/.
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#paleontology #paleontologist #dinosaur #sauropod #vertebra #fossil #evolution #coolscience #science #scienceart #teachersofinstagram #scicomm #womeninscience #ladyscientist #apatosaurus #pneumaticity

Recently at work I assisted my students with brain and eye dissections. This entailed cutting open the skulls of their cadavers and gently pulling the brains out while trying to preserve as much of the dura (outer protective covering), blood vessels, and nerves as possible. It was a truly incredible, touching experience, and made me reflect even more on the generous individuals who have allowed us to study their anatomy.
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Cadavers in medical schools are real dead bodies of real people who chose to donate themselves to science education while still alive. They were made completely aware of all the cutting and dissecting that would occur, and still elected to donate. Our summer gross anatomy course is nearing its end, and we’ll soon have a ceremony honoring our donors before the remains are cremated and returned to the families. I wanted to take a moment to express my profound gratitude to the 14 individuals whose bodies we have had the privilege of learning from this year. There is no substitute for seeing the real thing when it comes to anatomical structures, so our donors have played a critical role in the education of future doctors, dentists, and podiatrists.
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And in case you’re wondering, this is a sketch of a brain in inferior view (basically from the bottom) that I made to teach my students about a set of super important nerves coming directly off of the brain called “cranial nerves.” Out of respect for our cadavers we are not allowed to share photos of their bodies, so you get my teaching artwork instead!
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#science #scienceteacher #anatomy #anatomydrawing #cranialnerves #brain #cadaver #gratitude #ladyscientist #womeninscience #teachersofinstagram

Recently at work I assisted my students with brain and eye dissections. This entailed cutting open the skulls of their cadavers and gently pulling the brains out while trying to preserve as much of the dura (outer protective covering), blood vessels, and nerves as possible. It was a truly incredible, touching experience, and made me reflect even more on the generous individuals who have allowed us to study their anatomy.
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Cadavers in medical schools are real dead bodies of real people who chose to donate themselves to science education while still alive. They were made completely aware of all the cutting and dissecting that would occur, and still elected to donate. Our summer gross anatomy course is nearing its end, and we’ll soon have a ceremony honoring our donors before the remains are cremated and returned to the families. I wanted to take a moment to express my profound gratitude to the 14 individuals whose bodies we have had the privilege of learning from this year. There is no substitute for seeing the real thing when it comes to anatomical structures, so our donors have played a critical role in the education of future doctors, dentists, and podiatrists.
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And in case you’re wondering, this is a sketch of a brain in inferior view (basically from the bottom) that I made to teach my students about a set of super important nerves coming directly off of the brain called “cranial nerves.” Out of respect for our cadavers we are not allowed to share photos of their bodies, so you get my teaching artwork instead!
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#science #scienceteacher #anatomy #anatomydrawing #cranialnerves #brain #cadaver #gratitude #ladyscientist #womeninscience #teachersofinstagram

Sometimes there is confusion about #paleontology as a #science because we don’t always do experiments in a lab. This is because the earth has essentially already run lots of cool experiments for us! Fossils and geological clues are the data we collect and make our observations from, after formulating a research question and #hypothesis just like any other #scientist. .
Here is a shot of paleontological observations in action. With my colleagues, I am studying the #vertebrae of long-necked dinos (#sauropods). Pictured here is a #cervical vertebra (neck vert) from Apatosaurus. Our observations consisted of photographing and drawing the specimen, as well as taking measurements. In this case we’re looking for evidence that these animals were using their necks for battle, which we find in the form of the robust sticky-outy club you see projecting from the bottom of the vert. .
Shout-out to Matt Wedel (svpow.com) and Brian Engh (dontmesswithdinosaurs.com and Brian Engh Paleoart on Youtube) for letting me help out with this project! You guys are awesome collaborators and even better friends.
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#scientificmethod #brontosmash #teachersofinstagram #ladyscientist #womeninscience #fossil #apatosaurus #apato #sauropod #dinosaur #dino

Sometimes there is confusion about #paleontology as a #science because we don’t always do experiments in a lab. This is because the earth has essentially already run lots of cool experiments for us! Fossils and geological clues are the data we collect and make our observations from, after formulating a research question and #hypothesis just like any other #scientist. .
Here is a shot of paleontological observations in action. With my colleagues, I am studying the #vertebrae of long-necked dinos (#sauropods). Pictured here is a #cervical vertebra (neck vert) from Apatosaurus. Our observations consisted of photographing and drawing the specimen, as well as taking measurements. In this case we’re looking for evidence that these animals were using their necks for battle, which we find in the form of the robust sticky-outy club you see projecting from the bottom of the vert. .
Shout-out to Matt Wedel (svpow.com) and Brian Engh (dontmesswithdinosaurs.com and Brian Engh Paleoart on Youtube) for letting me help out with this project! You guys are awesome collaborators and even better friends.
.
#scientificmethod #brontosmash #teachersofinstagram #ladyscientist #womeninscience #fossil #apatosaurus #apato #sauropod #dinosaur #dino

My first find of the field season! This is a series of about three vertebrae...and that’s about all we can tell for now! 😂 These are probably from a #theropod dino or baby #sauropod dino.
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All of the fossils from this site are weathering out of extremely hard, coarse sandstone. Basically concrete. So we’re not yet removing anything, but instead are just documenting, drawing, photographing, and describing what we see in the rock.
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Something else challenging is that the fossils are all preserved in weird views and weird planes through the bone, which makes specific identification extra tricky (so it’s not surprising if these aren’t readily recognizable as vertebrae!). Fortunately my colleagues and I have spent a lot of time staring at CT scans of bones, so we’re pretty good at figuring stuff out from a random two-dimensional slice.
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Second pic is me holding a scale bar by two large chunks of bone found next to the vertebrae (which you can still see just to my left). No idea what these are...yet!!
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#fieldwork #science #scicomm #dinosaur #utah #bones #fossil #vertebrae #jurassic #womeninstem #ladyscientist

My first find of the field season! This is a series of about three vertebrae...and that’s about all we can tell for now! 😂 These are probably from a #theropod dino or baby #sauropod dino.
.
All of the fossils from this site are weathering out of extremely hard, coarse sandstone. Basically concrete. So we’re not yet removing anything, but instead are just documenting, drawing, photographing, and describing what we see in the rock.
.
Something else challenging is that the fossils are all preserved in weird views and weird planes through the bone, which makes specific identification extra tricky (so it’s not surprising if these aren’t readily recognizable as vertebrae!). Fortunately my colleagues and I have spent a lot of time staring at CT scans of bones, so we’re pretty good at figuring stuff out from a random two-dimensional slice.
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Second pic is me holding a scale bar by two large chunks of bone found next to the vertebrae (which you can still see just to my left). No idea what these are...yet!!
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#fieldwork #science #scicomm #dinosaur #utah #bones #fossil #vertebrae #jurassic #womeninstem #ladyscientist

I get to be a paleontologist this week!!! And to travel in one of the most gorgeous states.
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I’m out in #utah prospecting for #dinosaur fossils, and documenting previous finds. My colleagues and I are working in a layers of rock called the Morrison Formation. The stuff we’re looking at is about 152 million years old! We are mostly finding bones of #sauropods (long-necked dinos) and #theropods (meat-eating dinos).
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We spend every day, all day hiking around in 100+ degrees across rough terrain. Sometimes it kinda sucks, but all of the challenges are completely outweighed by the stunning geology and the beautiful skies and the thrill of communing with ancient extinct beasts. It’s almost a spiritual experience at times. Being a paleontologist is one of the best jobs in the world.
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This pic is rock exposures outside the Capitol Reef visitor’s center, nearby where we are doing out work.
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#science #scicomm #paleontology #ladyscientist #dinosaur #womeninscience #teachersofinstagram #fossil

I get to be a paleontologist this week!!! And to travel in one of the most gorgeous states.
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I’m out in #utah prospecting for #dinosaur fossils, and documenting previous finds. My colleagues and I are working in a layers of rock called the Morrison Formation. The stuff we’re looking at is about 152 million years old! We are mostly finding bones of #sauropods (long-necked dinos) and #theropods (meat-eating dinos).
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We spend every day, all day hiking around in 100+ degrees across rough terrain. Sometimes it kinda sucks, but all of the challenges are completely outweighed by the stunning geology and the beautiful skies and the thrill of communing with ancient extinct beasts. It’s almost a spiritual experience at times. Being a paleontologist is one of the best jobs in the world.
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This pic is rock exposures outside the Capitol Reef visitor’s center, nearby where we are doing out work.
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#science #scicomm #paleontology #ladyscientist #dinosaur #womeninscience #teachersofinstagram #fossil

Today I’m sharing more bone histology! This is a cross-section through the #femur of a hummingbird that was only about a week old when it passed (as seen under a miscroscope—it is super tiny!). The violet color is not natural—it is from a special stain I used to help better visualize cellular structures under the microscope.
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As you can see, the bone is super thin and the edges have an irregular appearance, which tells us this bone was still in the early stages of developing. However, what you see here was fully ossified and not just cartilage! The small spaces that look like sesame seeds are called osteocyte lacunae; there are where the bone cells “live.” The larger hole to the right is for a single blood vessel supplying this portion of the growing bone.
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#histo #hummungbird #histology #bone #ladyscientist #womeninscience #womeninstem #development #teachersofinstagram #science #scicomm #microscope #osteocytes #bird

Today I’m sharing more bone histology! This is a cross-section through the #femur of a hummingbird that was only about a week old when it passed (as seen under a miscroscope—it is super tiny!). The violet color is not natural—it is from a special stain I used to help better visualize cellular structures under the microscope.
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As you can see, the bone is super thin and the edges have an irregular appearance, which tells us this bone was still in the early stages of developing. However, what you see here was fully ossified and not just cartilage! The small spaces that look like sesame seeds are called osteocyte lacunae; there are where the bone cells “live.” The larger hole to the right is for a single blood vessel supplying this portion of the growing bone.
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#histo #hummungbird #histology #bone #ladyscientist #womeninscience #womeninstem #development #teachersofinstagram #science #scicomm #microscope #osteocytes #bird

Hello fellow lovers of dead things (and the friends/family who follow me to show support but don’t quite share my enthusiasm for dead things)! I’ve had a bit of an Instagram hiatus the past few weeks because I’m transitioning to a new job and moving.
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These days I spend all of my time teaching gross anatomy to medical students and dissecting cadavers (dream job!!!) but I thought I’d take a moment to share another cool skull video.
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This is a baboon skull from my collection. I didn’t skeletonize it personally—it came from a taxidermist, in fact. I love how similar it looks to a human skull! Sure, the canines are longer and the jaws are more elongate. But you can definitely tell we are pretty close relatives! The molars in particular are almost indistinguishable from ours. Enjoy! The feed will continue to be slow for a while still, but I’ll try to get a steady trickle going again.
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#science #scicomm #scienceart #womeninscience #womeninstem #teachersofinstagram #ladyscientist #womeninscience #skull #baboon #bones #skulllove #cranialanatomy

Hello fellow lovers of dead things (and the friends/family who follow me to show support but don’t quite share my enthusiasm for dead things)! I’ve had a bit of an Instagram hiatus the past few weeks because I’m transitioning to a new job and moving.
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These days I spend all of my time teaching gross anatomy to medical students and dissecting cadavers (dream job!!!) but I thought I’d take a moment to share another cool skull video.
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This is a baboon skull from my collection. I didn’t skeletonize it personally—it came from a taxidermist, in fact. I love how similar it looks to a human skull! Sure, the canines are longer and the jaws are more elongate. But you can definitely tell we are pretty close relatives! The molars in particular are almost indistinguishable from ours. Enjoy! The feed will continue to be slow for a while still, but I’ll try to get a steady trickle going again.
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#science #scicomm #scienceart #womeninscience #womeninstem #teachersofinstagram #ladyscientist #womeninscience #skull #baboon #bones #skulllove #cranialanatomy

Sharing another of my #ctscans today! This is the skeleton of a baby house finch. This little guy had barely hatched when he died.
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At this age, many parts of the #skeletalsystem are still cartilaginous. This scan has been rendered to only show ossified portions, which is why it looks a bit odd. You can also see very clearly that the #skull is formed by the fusion of several different bones—here they are unfused still! They’ll grow and fuse together as the baby matures. This is a #developmental pattern seen in many other vertebrates, including humans!
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#scicomm #science #scienceart #bird #livingdinosaur #macabre #skeleton #bones #birdanatomy #housefinch #development #teachersofinstagram #womeninstem #womeninscience #ladyscientist

Sharing another of my #ctscans today! This is the skeleton of a baby house finch. This little guy had barely hatched when he died.
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At this age, many parts of the #skeletalsystem are still cartilaginous. This scan has been rendered to only show ossified portions, which is why it looks a bit odd. You can also see very clearly that the #skull is formed by the fusion of several different bones—here they are unfused still! They’ll grow and fuse together as the baby matures. This is a #developmental pattern seen in many other vertebrates, including humans!
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#scicomm #science #scienceart #bird #livingdinosaur #macabre #skeleton #bones #birdanatomy #housefinch #development #teachersofinstagram #womeninstem #womeninscience #ladyscientist

And here’s a closeup of that #plastinated #pelican #liver. Bird livers are made up of two lobes, a right and a left, with the right lobe being the larger of the two. I’m always fascinated by the lobi-ness of livers. Some animals have five or six lobes (for instance, I’ve seen many in a rat liver)! This organ is connected via the hepatic vein to the stomach, intestine, and spleen.
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The coronary and falciform ligaments are what hold up this organ in the abdominal cavity, attaching it to the body wall anteriorly (falciform) and to other internal structures cranially (coronary). It’s actually very similar to the anatomy of our own liver!
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#anatomy #macabre #birdanatomy #dead #plastinating #plastination #science #scienceart #liver #comparativeanatomy #digestivesystem #teachersofinstagram #womeninscience #ladyscientist

And here’s a closeup of that #plastinated #pelican #liver. Bird livers are made up of two lobes, a right and a left, with the right lobe being the larger of the two. I’m always fascinated by the lobi-ness of livers. Some animals have five or six lobes (for instance, I’ve seen many in a rat liver)! This organ is connected via the hepatic vein to the stomach, intestine, and spleen.
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The coronary and falciform ligaments are what hold up this organ in the abdominal cavity, attaching it to the body wall anteriorly (falciform) and to other internal structures cranially (coronary). It’s actually very similar to the anatomy of our own liver!
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#anatomy #macabre #birdanatomy #dead #plastinating #plastination #science #scienceart #liver #comparativeanatomy #digestivesystem #teachersofinstagram #womeninscience #ladyscientist

The #liver is perhaps not the most exciting organ to look at, but it is pretty darn important! Here is a plastinated liver of a brown pelican that I made. It’s pretty big—actually in most vertebrates I’ve dissected the liver is the biggest, most prominent organ that you seen after cutting open the abdominal cavity. It is an organ with quite a few functions, ranging from helping us digest fats to breaking down old blood cells so they can be recycled.
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Illustration from Katrina van Grouw’s “The Illustrated Bird.”
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#scicomm #science #plastination #pelican #birdanatomy #scienceart #macabreart #macabre #womeninscience #ladyscientist #womeninstem #teachersofinstagram #bird

The #liver is perhaps not the most exciting organ to look at, but it is pretty darn important! Here is a plastinated liver of a brown pelican that I made. It’s pretty big—actually in most vertebrates I’ve dissected the liver is the biggest, most prominent organ that you seen after cutting open the abdominal cavity. It is an organ with quite a few functions, ranging from helping us digest fats to breaking down old blood cells so they can be recycled.
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Illustration from Katrina van Grouw’s “The Illustrated Bird.”
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#scicomm #science #plastination #pelican #birdanatomy #scienceart #macabreart #macabre #womeninscience #ladyscientist #womeninstem #teachersofinstagram #bird

Today I’m sharing a picture of a histological section through the femur of a red-tailed hawk. This was one of several hundred I made for my dissertation research.
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Histology is the study of tissues at the cellular level. Though I spend a lot of time studying gross anatomical structures, I also sometimes study biological patterns at the level of the cell, specifically in bone.
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It’s easy to just think of bone kind of as rock inside of us, but did you know it is very much a living tissue? It has its own special cells, called #osteocytes (osteo = bone and cytes = cells) and even a system of tiny blood vesseles running through it. In this pic the tiny black dots are the spaces where osteocytes lived, and the larger black lines are where the blood vessels were housed.
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Of course, I had to make it aesthetically pleasing! This photo was taken under a petrographic microscope using polarized light, a special way of bending the light that ends up changing the colors of your specimen. Geologists use this to better visualize certain minerals in thin sections of rock. Bone histologists use this because some features show up better than under regular light. I use it because it’s pretty!!! Okay, yeah, and the other actually scientific reason, too...
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#scicomm #science #scienceart #birdbone #bone #histology #bonehistology #redtailedhawk #birds #dinosaur #livingdinosaur #womenimscience #womenofstem #ladyscientist

Today I’m sharing a picture of a histological section through the femur of a red-tailed hawk. This was one of several hundred I made for my dissertation research.
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Histology is the study of tissues at the cellular level. Though I spend a lot of time studying gross anatomical structures, I also sometimes study biological patterns at the level of the cell, specifically in bone.
.
It’s easy to just think of bone kind of as rock inside of us, but did you know it is very much a living tissue? It has its own special cells, called #osteocytes (osteo = bone and cytes = cells) and even a system of tiny blood vesseles running through it. In this pic the tiny black dots are the spaces where osteocytes lived, and the larger black lines are where the blood vessels were housed.
.
Of course, I had to make it aesthetically pleasing! This photo was taken under a petrographic microscope using polarized light, a special way of bending the light that ends up changing the colors of your specimen. Geologists use this to better visualize certain minerals in thin sections of rock. Bone histologists use this because some features show up better than under regular light. I use it because it’s pretty!!! Okay, yeah, and the other actually scientific reason, too...
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#scicomm #science #scienceart #birdbone #bone #histology #bonehistology #redtailedhawk #birds #dinosaur #livingdinosaur #womenimscience #womenofstem #ladyscientist

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@theladyanatomica

IMG_3365.HEIC

My interests are in the fields of comparative anatomy, vertebrate paleontology, and evolutionary biology. My research is question-driven, and I study a variety of organisms from birds to sauropod dinosaurs by integrating neontological and paleontological data. I am an anatomist, with a personal comparative teaching collection of skeletons, skulls, and plastinated specimens, many of which I have prepared myself.

Home: About Me

Recent Publications

For a complete list of publications (and PDF downloads) click here.

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Osteohistology of Enantiornithine Birds from the Lower Cretaceous Xiagou Formation

Atterholt et al., 2025

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Description and Osteohistology of Two Early Immature Enantiornithines (Aves: Ornithothoraces) from the Early Cretaceous Jehol Biota

O'Connor et al., 2025

Home: Skills

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A New Enantiornithine (Aves: Ornithothoraces) from the Lower Cretaceous Xiagou Formation with Unusually Short Pubes

O'Connor et al., 2025

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