Griffin Lab

The billion-dollar case for sustaining palaeontology’s digital databases - Nature Ecology & Evolution The authors survey community palaeontological databases, documenting their contributions to science as well as their vulnerabilities, and provide recommendations for the future of open science databas...

🚨 Hot off the press: Our look into of the palaeontological database landscape and its sustainability into the future.

Palaeo databases are invaluable and continue to transform our research field - but they are vulnerable... (1/6) 🧪 ⛏️

www.nature.com/articles/s41...

A beautiful cake with chocolate icing and strawberries

In bird embryology you occasionally get an unfertilized “dud” egg. @lnwilson.bsky.social, not wanting her emu eggs to go to waste, used a dud egg to make a beautiful cake for the lab!

For your delight and amusement, here are some dinosaur gastroliths, underneath the ribs of an Early Jurassic sauropodomorph from Zimbabwe 🦖🇿🇼

Not a big baby Multipronged approaches resolve the debate about the Nanotyrannus fossil species

Not a big baby! My commentary in @science.org about the latest Nanotyrannus research. www.science.org/doi/10.1126/...

Why does life explore so few of the forms it could possibly take? Using fractal descriptors, this #scienceadvances paper shows that Earth’s biosphere clusters around simple shapes, reflecting deep evolutionary constraints. @artemyte.bsky.social @manlius.bsky.social www.science.org/doi/pdf/10.1...

a man wearing a beanie and a black jacket is smiling and holding a piece of food . ALT: a man wearing a beanie and a black jacket is smiling and holding a piece of food .

Our lab is growing: we will have openings for student and staff positions throughout the year. Please visit edwards-lab.org for the most up to date job positions. I am excited to work with the department and looking forward to the months ahead!

Evidence for high-frequency hearing in a Permian stem reptile - Nature Communications Hearing evolved in most amniotes by the late Permian, but its origins in reptiles remain poorly understood. Here, using biomechanical and morphometric analyses, the authors show that high frequency hearing likely had evolved in reptiles by the late Permian.

A few new papers out recently that I'm excited to share with you!

First: How well could stem reptiles hear?

www.nature.com/articles/s41...

Another cool paper, glad to see it finally out:

www.nature.com/articles/s41...

Figuring out the range of error that exists, & factors influencing offsets, between growth marks and ontogenetic age remains a challenge for estimating growth curves from bone histo data.

More work like this is needed.

This was done with an Original Prusa XL, highly recommended

A row of painted 3D printed skulls on a table

A group of painted 3D printed skulls on a table

The Vertebrate Paleontology students did a great job 3D printing and painting skulls—look at that homology!

The discovery that Nanotyrannus is a distinct species from the T-rex indicates complex food web and interspecies interactions in the Dinosaur world. This research was funded by NSF post-doc grants, which were just archived, i.e., they're no longer available.

news.yale.edu/2025/12/04/t...

Congratulations to UMMP Associate Research Scientist Miriam Zelditch on the release of the third edition of the indispensable "Geometric Morphometrics for Biologists" (a.k.a. the green book)! #FossilFriday

Volume renderings of CT scan data of the holotype skull of Nanotyrannus lancensis (CMNH 7541). The top image is mostly a left lateral view. The bottom image is a ventral view showing the caudal half of the hyoid bone preserved in place.

Additional images (all in ventral view) of the holotype skull of Nanotyrannus lancensis (CMNH 7541). The top right image is from the original 1946 article by Charles Gilmore showing the full ceratobranchial hyoid bone in place. The bottom photograph (that I snapped in 2005 when I had the skull on loan for study & CT scanning) shows the caudal half of the hyoid bone preserved in place. The top left image is similar to the bottom image but is grayscale except for the hyoid bone.

The main photograph (again, that I snapped in 2005 when I had the skull on loan for study & CT scanning) shows the caudal half of the hyoid bone of Nanotyrannus (CMNH 7541) preserved in place, but it's more of a front view. Notice the broken end of the ceratobranchial in a close-up in the inset.

#FossilFriday The awesome new article in Science by
@griffinlabpaleo.bsky.social et al. adds more evidence for the validity of Nanotyrannus by showing that the hyoid bone in the holotype has adult bone histology. Here are some more images showing the ceratobranchial bone in place in the skull. 🦖

The development of a single zebrafish retina captured on a light sheet microscope approx. every 12 hours from 1.5 days to 3.5 days after birth of the embryo. The retinal ganglion cells are labelled with Ath5:RFP (magenta) the amacrine and horizontal cells are labelled with Ptf1a:YFP (yellow) and the photoreceptors and bipolar cells are labelled with Crx:CFP (cyan). The image was created in the Norden lab at the MPI-CBG, Dresden. Credit text to Wikimedia Commons.

Development of the zebrafish retina captured on a light sheet microscope. Credit to @ichajaroslav.bsky.social. #ZebrafishZunday 🧪

Just emailed it to you!

I forgot image credit, I apologize! This is by Andrey Atuchin, courtesy the Cleveland Museum

Thanks to all our collaborators, the taggable ones are @ashpoust.bsky.social , @mfabbri.bsky.social , @rileysombathy.bsky.social ! Extra thanks to the Cleveland Museum, the Yale Peabody Museum, and the LA Natural History Museum for allowing crucial sampling of their specimens (12/12)

Nanotyrannus and Tyrannosaurus coexisted at the close of the Cretaceous - Nature A well-preserved skeleton of a nearly mature tyrannosaur from the Hell Creek Formation in Montana, USA supports the existence of a second Nanotyrannus species, Nanotyrannus lethaeus sp. nov., and vali...

Really nice work by @jgn-paleo.bsky.social & Zanno reached this same conclusion from independent lines of evidence/specimens just a few weeks ago. Our papers converge on the same conclusion, mutually bolstering each other (11/12)
www.nature.com/articles/s41...

We have uploaded all high-resolution, whole-slide images in all light regimes onto Dryad, available for anyone to download, study, and compare (10/12)

doi.org/10.5061/drya...

A Nanotyrannus individual facing off with a juvenile and an adult Tyrannosaurus rex

So the Nanotyrannus type specimen is full-size, or nearly so. We discuss more in the paper why we don’t find it likely that this is simple intraspecific variation in T. rex, sexual dimorphism, or a congenital dwarfism. The best explanation is that Nanotyrannus is distinct from Tyrannosaurus (9/12)

a comparison of hyoid bone histology

Three Tyrannosaurus rex individuals of different growth stages on display at the Los Angeles museum

This is especially apparent when we compare to a juvenile T. rex hyoid from the LACM. Despite being smaller in size, the Nano hyoid shows a close package of external growth marks that is the classic indicator of skeletal maturity (8/12)

All that was left was to test the Nanotyrannus type specimen, the skull that formally defines the species Nanotyrannus lancensis. At the time, it was the general consensus that Nano was a juvenile T. rex, so we were surprised to find every indication of maturity in the hyoid (7/12)

Then, we had to establish that it worked in extinct dinosaurs, especially large theropods. Running the size gamut from Coelophysis to Allosaurus to two definitive Tyrannosaurus individuals, we showed that hyoid microstructure works well! Not quite as precise as limbs, but it gets the job done (6/12)

First, we had to establish that hyoid histology worked to gauge maturity in living relatives of dinosaurs of known growth stages. We showed that it did, in a growth series of Ostrich, Alligator, and even a Dwarf Caiman. Step one, done! (5/12)

A drawing from an old scientific paper of the underside of a tyrannosaur skull, with an arrow pointing to the hyoid

A 3D render of a tyrannosaur skull with the hyoid highlighted in green

The Nano skull does have ‘hyoids’, tubular throat bones. During a visit to the Cleveland Museum of Natural History, curator Caitlin Colleary and I wondered if these might also contain a record of growth, and allow us to directly test maturity in the name-bearing specimen (4/12)

A woman standing behind a small tyrannosaur skull

An image of bone histology of an Alligator femur, with growth lines highlighted

The best way to tell a dinosaur’s maturity is by looking at the bone microstructure (histology) of limb bones. However, the type specimen of Nanotyrannus is an isolated skull, so this method wasn’t viable. This difficulty resulted in the longest-running current debate in dinosaur paleontology (3/12)

A drawing of a tyrannosaur skull from an old scientific paper

A black & white photo of a paleontological dig with an old truck

A black & white photo of three men standing by a crate that says “FOSSILS DO NOT DROP”

There has been a debate since the skull’s discovery in 1942: whether Nano was a small-bodied tyrannosaur that lived with Tyrannosaurus, or just a juvenile T. rex. This has major implications for how we understand T. rex growth and carnivores within last ecosystems to host non-bird dinosaurs (2/12)

Very excited to share that our latest paper is out in Science! We show that the type specimen of Nanotyrannus—an isolated skull—is fully grown, showing that it is not a juvenile Tyrannosaurus rex but a distinct species (1/12)
www.science.org/doi/10.1126/...

'Tis the season for graduate school applications, so here's a reminder that I'm recruiting! My lab uses a combination of fossils, statistical phylogenetics, fieldwork, & computational methods to study macroevolutionary dynamics in the marine biosphere. Check the link below & feel free to reach out

Life restoration by Matheus Fernandes showing a Triassic scene with the lagerpetid non-pterosaurian pterosauromorph Ixalerpeton with early pterosaurs flying overhead. The publication is here: https://www.cell.com/current-biology/fulltext/S0960-9822(25)01467-8

Life restorations and labeled cranial (brain) endocasts of the lagerpetid Ixalerpeton and the pterosaur Allkaruen.

Happy to be a part of this big project led by Mario Bronzati & Matteo Fabbri—out today #OA in @currentbiology.bsky.social
bit.ly/3M5weun —on the brain endocast of a close pterosaur cousin & what it means for pterosaur brain evolution...maybe different from bird brain evolution. 1/2