A new study by Katy Prentice, done as part of her undergraduate degree (MSci in Palaeontology and Evolution) at the University of Bristol, shows that the pterosaurs evolved in a most unusual way, becoming more and more specialised through their 160 million years on Earth. The work is published today in the Journal of Systematic Palaeontology.
'Usually, when a new group of animals or plants evolves, they quickly try out all the options. When we did this study, we thought pterosaurs would be the same,' said Katy. 'Pterosaurs were the first flying animals they appeared on Earth 50 million years before Archaeopteryx, the first bird and they were good at what they did. But the amazing thing is that they didn't really begin to evolve until after the birds had appeared.'
Katy's study was done in conjunction with her supervisors, Dr Marcello Ruta and Professor Michael Benton. They looked at 50 different pterosaurs that ranged in size from a blackbird to the largest of all, Quetzalcoatlus, with a wingspan of 12 metres, four times the size of the largest flying bird today, the albatross. They tracked how all the pterosaur groups came and went through their history and recorded in detail their body shapes and adaptations.
The new work shows that pterosaurs remained conservative for 70 million years, and then started to experiment with all kinds of new modes of life. After birds emerged and became successful, the pterosaurs were not pushed to extinction, as had been suggested. It seems they responded to the new flyers by becoming larger and trying out new lifestyles. Many of the new lifestyle adaptations were seen in the pterosaurs skulls, as they adapted to feed on different food sources; some were seed-eaters, many ate fish, and later ones even lost their teeth. The rest of the body also showed a surprising amount of variation between different groups, when considering that the body forms have to retain many features to allow flight
|Contact: Hannah Johnson|
University of Bristol