MadSci Network: Evolution |
re-evolution of dinosaurs
The Dinosaurs are extinct members of the larger group of vertebrates known as the archosauria, the living members of this group include the crocodiles and birds. As a group, the archosaurs separated from the the other main types of reptiles, the turtles and the snakes and lizards (the lepidosauria) approximately 250 million years ago (the dinosaurs as a group went extinct approximately 65 million years ago. |
Now, to answer your question, is it possible for this process to run in reverse? In theory, the answer is yes in the sense that a population of modern crocodiles could find themselves living under conditions where, over millions of years, and in specific environments, their ancestors could come to look like dinosaurs (upright in poster, rather than sprawling). However, it is extremely unlikely that the organisms that resulted would be dinosaurs - they would differ in lots of anatomical and genetic details. In a sense, it would be an example of convergent evolution, in which organisms that are similar are formed from different ancestors. |
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