We focus on great transitions in the history of vertebrates. In the field and in the lab, we use the geological record of life to guide questions about major transformations across Vertebrata, especially at the origins of extant radiations such as (but not limited to) birds, mammals, tetrapods, and gnathostomes. To address the nature and mechanism of pivotal events at crucial points in evolutionary history, we bring to bear a full range of modern biological and geological techniques, especially molecular developmental biology and functional biology, coupled with advanced three-dimensional imaging and geometric analysis. However we maintain a surpassing commitment to the discovery of new fossils in the field; these will always be the inspiration, the grist, and the final validating test for work on the history of life.

We operate at the core of the immensely rich paleontological research, teaching, and curatorial community at Yale and are prepared to support promising research across the entire chordate radiation and at any timescale. Yale’s paleontology, geobiology, and biology faculty and staff, spread across several departments, collectively have the resources and expertise to guide students and other researchers in work on all parts of the vertebrate tree.

We are also interested in more fundamental questions of vertebrate development from a molecular developmental and genomic perspective, particular regarding structures and functions of biomedical and evolutionary significance.


Our laboratory spaces include a complete molecular developmental lab with cell-culture facilities, permitting the full range of modern developmental biology investigations on model and non-model vertebrates. Yale additionally has a state-of-the-art high-resolution CT scanning facility to which we have full access. We add to these Yale’s traditional strengths in the form of the staff and collections of the Peabody Museum of Natural History, among them the third-largest paleontology collection in the nation, and consistent annual endowed support and a small fleet of vehicles for several paleontological field programs, including multiple yearly expeditions focused on vertebrates, virtually unparalleled among university-based paleontology programs. Students and staff have a great deal of say in the places and strata we explore each year.

3D volumetric rendering of above gecko embryo with nerve channel deactivated, showing cartilage in orange and muscle in red. Image credit: Daniel Smith-Paredes

01 ichthyornis painting and skull colored.png

CT-based 3D reassembly of the skull of the stem bird Ichthyornis dispar, which had a transitional beak, a derived brain, and a primitive jaw muscle attachment region. Image credit: Michael Hanson

CT rendering of skull of Velociraptor. Image credit: Bhart-Anjan Bhullar

05 Sphenosuchian lateral 01.jpg

CT rendering of skull of undescribed stem crocodile collected by Yale Peabody expeditions to the Triassic of Utah. Image credit: Bhart-Anjan Bhullar

06 Quail foot cartilage nerves.jpg

Volumetric rendering from laser-scanning confocal data of quail foot immunostained for nerve (red) and cartilage (green). Image credit: João Botelho

07 Tweet 01 figure 02.jpg

Summary figure showing inner ear evolution and behavioral correlates in Reptilia. Image credit: Michael Hanson

08 future 02 arm.JPG

Volumetric renderings from laser-scanning confocal data of embryonic alligator (left) and quail (right) arms, immunostained for cartilage (blue) and muscle (red). Image credit: Daniel Smith-Paredes

Volumetric rendering of laser-scanning confocal data of early gecko embryo immunostained for nerve (white) and muscle (red). Image credit: Daniel Smith-Paredes

09 Gecko embryo 12 days incubation nerves and muscle.jpg
10 Alligator embryo stained for muscle nerve and cell nuclei.jpg

Alligator embryo immunostained for cell nuclei (blue), nerve (green), and muscle (orange). Image credit: João Botelho

11 02 FINAL_braincases4-01.jpg

CT renderings of brain endocasts and skull roof/braincase bones of important fossil taxa on the line to birds. Image credit: Matteo Fabbri and Bhart-Anjan Bhullar

Research image gallery

02 general Gecko_muscles_nerves_01.JPG

3D volumetric rendering from laser-scanning confocal data of gecko embryo, clarified using a modified CLARITY protocol and immunostained for nerve (blue), cartilage (orange), and muscle (red). Image credit: Daniel Smith-Paredes

03 general Gecko_muscles_cartilage_01.JPG
04 Velociraptor_mongoliensis 2.jpg