By Corey Charlton for MailOnline Dinosaurs walked the earth about nine million years earlier than once realised, with recent discoveries of their cat and dog-sized ancestors providing the key to understanding their evolution. Research has revealed small creatures which roamed the earth 245million years ago are likely to have been the immediate ancestors of dinosaurs such as the Tyrannosaurus rex and velociraptor. One of these is a labrador-sized carnivore, first discovered in Africa, which had a metre long tail and lived alongside other reptile-type species 243million years ago. Nyasasaurus, pictured in the foreground, was an ancestor to the dinosaurs and about the size of a labrador
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Dinosaurs evolved from small cat and dog-sized creatures 249m years ago
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The species survived a mass extinction, after which dinosaurs evolved
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Footprints found in Poland and bones in Africa give clues about creatures
He added the @placeholder quarry footprints, which he worked on, 'may provide a new frontier in understanding the evolution of early dinosaurs'.