Squamates are a group of reptiles that include lizards and snakes, with the earliest fossils occurring in the Jurassic, despite molecular studies dating the group back to the Triassic. The study of their origins has been contentious because of this gap, and the lack of fossils during this time period.

However, a new look at a previously-known fossil has changed our view of squamate origins, and discussing this animal and what it means about reptile relationships and squamates is Dr. Tiago Simões of the University of Alberta. This episode is based on a new paper published in Nature by Dr. Simões and colleagues.

Direct download: Ep92.mp3
Category:general -- posted at: 6:00pm UTC

The Appalachian mountains, span the Eastern margin of the United States of America. They are predominantly composed of Paleozoic rocks, but Mesozoic marine sediments (formed adjacent to the Appalachian continent at the time) can be found along the Eastern coast. It is within these deposits that the remains of a unique dinosaur fauna can be found.

Joining us to paint a picture of the vertebrate faunas of Appalachia during the Mesozoic is Chase Brownstein, research associate at the Stamford Museum and Nature Centre.

Direct download: Ep91.mp3
Category:general -- posted at: 2:29pm UTC

Bird evolution has long fascinated palaeontologists. Despite crown-group birds (birds giving rise to modern lineages today) evolving during the Cretaceous, there are relatively few fossils from this time, making it difficult to understand this key time period and just exactly how modern birds came to be.

Dr Daniel Field, 50th Anniversary Prize Fellow from the University of Bath, studies bird evolution, particularly how crown-group birds evolved. In this episode, we discuss his recent paper on an exceptionally preserved Ichthyornis specimen, and it’s significance in understanding how modern birds came to be.

Direct download: Ep90.mp3
Category:general -- posted at: 7:52am UTC