One of the biggest debates in the dinosaur world is what was happening right before they went extinct. Were they already declining, or would they have thrived if not for the asteroid? Two recent studies shed some light on this question: one that analyzes a trove of fossils from New Mexico and suggests there was more diversity in the Americas than previously thought, and another that reanalyzes a long-debated juvenile T. rex fossil and finds it’s likely a separate, smaller species.

Host Ira Flatow is joined by authors on those separate studies, paleontologists Steve Brusatte and Lindsay Zanno.

Guests: Dr. Lindsay Zanno is division head of paleontology at the North Carolina Museum of Natural Sciences in Raleigh, NC.
Dr. Steve Brusatte is a paleontologist at the University of Edinburgh in Scotland.

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