Casey Holliday
banner
crocholliday.bsky.social
Casey Holliday
@crocholliday.bsky.social
Anatomy, morphology, evolutionary biology, developmental biology, biomechanics, paleontology, imaging, maybe crocodiles
Calling Midwest Anatomists and Paleontologists!
Deadlines Extended! Sept 1st for Talks and Posters! Sept 12th for registration. Look forward to seeing you here! @anatomyorg.bsky.social @paleosoc.bsky.social @societyofvertpaleo.bsky.social

www.anatomy.org/.../Meetings...
August 24, 2025 at 5:17 PM
Congratulations to Emma Cooney on graduating with a MS out of the lab. Stay tuned for some wicked cranial
morphology.
May 19, 2025 at 9:49 PM
Happy to meet new people and share our work on imaging and informatics at @bionexuskc.bsky.social in Kansas City.
April 11, 2025 at 2:04 PM
Good times with good people at AAA this week!
April 4, 2025 at 10:55 PM
March 19, 2025 at 8:19 PM
This means that the temporal muscles of birds are more fore-aft oriented compared to the more vertical muscles of their dinosaur ancestors. This shows a change in feeding behaviors, from bitey, stiff skulls of early dinosaurs to dexterous, flexible-headed birds. Art by Corrine Cranor.
March 18, 2025 at 3:20 PM
Meanwhile, we also project these vectors as ternary plots to get a general sense of orientation change. In general, you might see how many temporal muscle dots start at the top of the plot in Allosaurus and then plinko their way down along the RC (rostrocaudal) axis along the line to birds.
March 18, 2025 at 3:20 PM
Meet our vector bouquets: orientations and magnitudes of jaw muscles projected as colored vectors and here plotted from a common origin on a single taxon, Dromaeosaurus, to show a phylogenetic change in muscle orientation.
March 18, 2025 at 3:20 PM
The supplementary info hosts a number of plates documenting the muscle attachment sites we used to model jaw muscles. The centroids of each of these surfaces were used to estimate orientation vectors while the we also used them to model volumes which were used in estimating muscle forces.
March 18, 2025 at 3:20 PM
Some birds use their protractor muscles to actively power cranial kinesis, but inferring this function in fossils is challenging. We compared 3D resultants of protractor muscles to orientations predicted palatal movement and found the muscles weren’t optimized for powering kinesis until Neognaths.
March 17, 2025 at 10:15 PM
Compared to even their Cretaceous ancestors, living birds have fewer struts and linkages in their skulls, resulting in a higher potential for cranial kinesis, the ability of birds to move multiple joints in their skulls. Think about how a parrot can use its upper beak as an extra limb.
March 17, 2025 at 10:10 PM
We reviewed palatal morphologies across a variety of Mesozoic birds. Many changes the palate occurred, namely the breakdown of linkages between the quadrate, epipterygoid and braincase. Much of this change maybe be hidden in the developmental biology of the palatoquadrate cartilage.
March 17, 2025 at 10:07 PM
We figured out how to calculate 3D resultant vectors of jaw muscles in a modeled sample of living and extinct dinosaurs and found that a number of muscles change orientations and proportions as the brain got big and changed head shape during the origin of birds.
March 17, 2025 at 10:04 PM
Movers and shakers in the lab: Chris, Aryan, Corrine, John, Cerise and whiteboard.
March 12, 2025 at 10:31 PM
Lab had a great time at the Columbia Young Scientist Expo. Constant parade of families keen on discovery.
March 11, 2025 at 1:26 PM
Hey folks!!! Come join us at Mizzou this October for a Paleo-Themed @anatomyorg.bsky.social Regional Meeting: PALEO CONNECTED.
Sponsored in part by @paleosoc.bsky.social, we're looking forward to having you all. Watch this space.
February 14, 2025 at 10:33 PM
Who says birds don’t have teeth?
February 7, 2025 at 2:36 PM
We’re cleaning some lab spaces to make way for impending construction. Found an entiantiornithine fossil high up on a shelf with some other skeletons. New taxon methinks.
February 5, 2025 at 4:22 PM
Got to see the latest Squirrel-raptor at The Field Museum. Its exquisite preparation was done by Connie Van Beek and Akiko Shinya. Here’s Connie working on a more recent bird from the Green River Fm., a similar type of slab fossil, just ~90degrees of Eocene longitude away and ~90million yrs later.
January 23, 2025 at 5:37 PM
This was me in 1998 with Sue's exquisite left femur, side burns and hair! c/o Nat Geo. Her neck block is still in the jacket in the background.
January 22, 2025 at 6:09 PM
Got to visit the Field Museum Friday. Got my picture with Geology Collections Manager Bill Simpson. Bill helped get me started in this grand adventure in Paleo. I’m forever grateful to him and all the rest of the Sue prep team, who still let me hang in the lab when I show up with my own students.
January 21, 2025 at 8:16 PM
Best lab photo ever
January 6, 2025 at 8:45 PM
January 1, 2025 at 2:42 PM
Nesting prints of different layers of tongue muscle architectures
December 21, 2024 at 11:54 PM
3D print ready for painting over the holidays.
December 18, 2024 at 9:42 PM