Portrait of Jack Tseng kneeling next to a large fossil skull of an extinct rhino, with rows of specimen cabinets in the background at the University of California Museum of Paleontology.

Research Bio

Jack Tseng is an associate professor in Integrative Biology.  Research in his laboratory is focused on understanding the macroevolutionary-scale patterns of structure-function relationships in mammals and other vertebrate groups. Projects in his lab include analysis of variables such as dietary and locomotor ecology, evolutionary relationships, and their interplay on the structure and function of the vertebrate skeleton. He uses methodologies such as landmark-based shape analysis (geometric morphometrics), model-based assessments of feeding performance (finite element analysis) as well as experiment-based model validation approaches (mechanical testing and kinematics analysis). He also conducts field-based and collection-based research on extinct mammal groups to understand the influence of inter-continental dispersals on the evolution of predator lineages. His fieldwork areas including Wyoming (Eocene), Inner Mongolia (Neogene), Tibetan Plateau (Neogene), Mexico (Neogene), and southern China (Paleocene).

Research Expertise and Interest

paleontology, jaws, bite force, macroevolutionary trends and patterns, mammals, vertebrates, evolution, vertebrate evolutionary morphology, mammalian systematics, evolution of form and function

In the News

Was This Hyena a Distant Ancestor of Today’s Termite-Eating Aardwolf?

Of the hundred or so known species of hyena — living and extinct — that stalked the earth, all have been meat eaters or omnivores except one, the aardwolf, which, mysteriously, eats termites. What happened in the history of fearsome hyenas that led one group to give up raw meat and turn to insects? Two fossil skulls of a 12- to 15-million-year-old hyena that once lived in the Gansu province of China may shed light on that mystery.

Featured in the Media

Please note: The views and opinions expressed in these articles are those of the authors and do not necessarily reflect the official policy or positions of UC Berkeley.
June 2, 2021

Teen T. Rex Could Deliver Bone-Puncturing Bites From Age 13 Before Its Adult Teeth Even Came In, Study Finds

Daily Mail
Sam Tonkin
A teenage Tyrannosaurus rex had a much more powerful bite than previously thought, a study has found, and was able to deliver a bone-puncturing crunch before its adult teeth even came in. At the age of 13, T.Rex was able to exert up to 5,641 newtons of force - somewhere between the jaw forces of a hyena or crocodile. Bite force measurements can help paleontologists understand the ecosystem in which dinosaurs lived, as well as which predators were powerful enough to eat which prey, and what other predators they competed with. "If you are up to almost 6,000 newtons of bite force, that places them in a slightly different weight class," said Jack Tseng, assistant professor of integrative biology at University of California, Berkeley. "By really refining our estimates of juvenile bite force, we can more succinctly place them in a part of the food web and think about how they may have played the role of a different kind of predator from their larger, adult parents." For more on this, see our press release at Berkeley News. Stories on this topic also appeared in Phys.org and Fox 11 News.
FullStory


Teaching

Courses taught during the three most recent terms
2026 Spring

  • Directed Undergraduate Research  [INTEGBI 191]  

  • Supervised Independent Study and Research  [INTEGBI 199]  

  • Research Seminar  [INTEGBI 291]  

  • Special Study in Integrative Biology  [INTEGBI 298]  

  • Graduate Research  [INTEGBI 299]  

  • The Animal In You: Evolutionary Traces In The Human Body  [INTEGBI 38]  

  • Supervised Independent Study and Research  [INTEGBI 99]  

  • Thesis Course  [INTEGBI H196A]  

  • Thesis Course  [INTEGBI H196B]  

2025 Fall

  • Morphology of the Vertebrate Skeleton with Laboratory  [INTEGBI 184L]  

  • Supervised Internship  [INTEGBI 197]  

  • Supervised Independent Study and Research  [INTEGBI 199]  

  • Special Study in Integrative Biology  [INTEGBI 298]  

  • Graduate Research  [INTEGBI 299]  

  • Thesis Course  [INTEGBI H196A]  

  • Thesis Course  [INTEGBI H196B]  

  • Supervised Research: Biological Sciences  [UGIS 192C]  

2025 Summer

  • Supervised Internship  [INTEGBI 197]  

  • Supervised Independent Study and Research  [INTEGBI 199]  

  • Thesis Course  [INTEGBI H196A]  

  • Graduate Research  [INTEGBI N299]  

2025 Spring

  • Directed Undergraduate Research  [INTEGBI 191]  

  • Supervised Independent Study and Research  [INTEGBI 199]  

  • Paleontology Seminar Series  [INTEGBI 287]  

  • Research Seminar  [INTEGBI 290]  

  • Research Seminar  [INTEGBI 291]  

  • Special Study in Integrative Biology  [INTEGBI 298]  

  • Graduate Research  [INTEGBI 299]  

  • Life During the Age of Dinosaurs  [INTEGBI 33]  

  • Supervised Independent Study and Research  [INTEGBI 99]  

  • Thesis Course  [INTEGBI H196B]  

  • Supervised Research: Biological Sciences  [UGIS 192C]