2020 - 2021 session

The University lecture rooms remain closed, and so the following meetings

will be held via video using the  Zoom system

8th June: Dr David Button (Natural History Museum)

Putting flesh on old bones: reconstruction of feeding ecology and its role in the early evolution of Dinosauria

After their first appearance about 240 million years ago, early dinosaurs exhibited substantial increases in maximum size, diversity and abundance through the Late Triassic and Early Jurassic. Dinosaur evolution during this interval has been suggested to represent an adaptive radiation, with expansion into new ecological niches and novel feeding behaviours. However, cranial material from early dinosaurs is rare, and has often been distorted during fossilisation, and there have been no biomechanical modelling studies conducted across early Dinosauria. Consequently, the functional anatomy and feeding behaviour of early dinosaurs are poorly understood, preventing evaluation of the dynamics and drivers of the radiation of Dinosauria.

 

To address this, we performed virtual reconstruction of the skulls and jaw musculature of early dinosaur taxa. These data were then used to conduct finite element analyses (FEA) of the skulls of these dinosaurs, allowing calculation of functionally induced stresses and strains during simulated feeding behaviours. Sensitivity analyses indicate that results are robust to uncertainties due to the fossilisation process. Further, biomechanical performance is observed to vary more closely with hypothesised feeding ecology than gross anatomical similarity, showing that results are useful in interpreting the evolution of early Dinosauria. 

 

Very different patterns are observed between individual early dinosaur clades. Early theropods exhibit functional constraints suggesting they were small-prey specialists, not expanding into apex predator roles until the Jurassic. Similarly, comparison of early-diverging members of major ornithischian clades indicates the exploration of a range of dietary strategies during the Early Jurassic. This is consistent with both of these clades invading newly vacant ecological niches following the end Triassic mass extinction. By contrast, sauropodomorphs underwent ecological radiation earlier, in the Late Triassic, but this was related more to increases in body size than in cranial morphology. The asynchronous radiation of different dinosaur clades highlights the different evolutionary histories and unique character combinations of each. Nonetheless, the radiation of all three of the major dinosaur radiations appears to have been opportunistic, associated with invasion of vacant ecological niches, as opposed to competitive replacement of other groups during the Trias

 

- invitation to this zoom talk has been sent via email to WEGA members

 

 

 

 

 

Please login into the zoom system between 7 and 7.25 pm, as once the lecture starts it is difficult for Judy to keep track of the talk, waiting room and zoom messages.

Other dates yet to be confirmed

        

WEGA members will be emailed with the invitation to each of these zoom meetings separately