Palaeocast

One of the great themes in palaeobiology is the water-land transition, or how and when the ancestors of today’s four-legged terrestrial animals moved to land. Lines of questioning have included understanding the anatomy and biomechanics of the axial skeleton- head and vertebrae (focusing on biting and swallowing) and the appendicular skeleton (focusing on how the earliest tetrapods walked or swam). Our picture of this story has drastically changed in the last three decades, as new fossils have filled in crucial gaps in the tetrapod evolutionary tree. This changing picture really came to the fore with the work of the late Professor Jenny clack, who’s work at Cambridge in early tetrapods from Greenland and elsewhere  brought the water land question back in fashion. 

Joining us to discuss Jenny Clack's Legacy in this episode are Prof. Mike Coates and Ben Otoo both of the University of Chicago. 

Direct download: Ep110.mp3
Category:general -- posted at: 5:36pm UTC

Early tetrapods include the earliest animals to grow legs, and their closest ancestors. Moving from the water to land required a number of changes within the skeleton and muscular system, related to moving from swimming to crawling, greater pressure on the body after experiencing further effects of gravity without buoyancy, and the difference in feeding with and without water. This transition is commonly referred to as the 'water-to-land' transition. While a significant amount of work has been done on the anatomical changes through this period, there has been less study on the biomechanics. What has been looked at tends to relate to the mechanical changes related to walking on land and the limbs. However, less has been done looking at the skull mechanics and feeding.

Early tetrapod work was pioneered by Professor Jenny Clack. She did a lot of early field work and description, understanding this transition better than anyone. Sadly, Professor Clack passed away in March, but has left behind a legacy of other professors, post docs and students around the globe which she inspired. In this episode, we talk to Dr Laura Porro from University College London about her work on early tetrapod feeding and skull mechanics, and how the skull changed over the water-to-land transition, work which was done with and inspired by Jenny.

Direct download: Ep109.mp3
Category:general -- posted at: 11:05am UTC

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