![]() ![]() ![]() Credit: Emily Willoughby Wikimedia (CC BY-SA 4.0) According to its describers, it is not a bird. This reconstruction, by Emily Willoughby, depicts Serikornis from the Upper Jurassic of China. Mesozoic maniraptoran dinosaurs that possess all kinds of bird-like and not-so-bird-like combinations of anatomical characters are published all the time. None of these taxa is at all birdlike and all clearly belong elsewhere in reptile phylogeny. These authors argue that a number of peculiar Triassic reptiles – they include Megalancosaurus, Cosesaurus, and Longisquama and have been dubbed avimorph thecodonts – might represent the real closest relatives of birds. Supposedly, theropods are too large and too specialized for terrestrial cursoriality to give rise to birds, possess anatomical characters that bar them from avialan ancestry, and appear too late in the Mesozoic record to be ancestral to Archaeopteryx (e.g., Martin 1983 Feduccia 1996, 2002). Some ornithologists and paleontologists argue that theropods cannot be ancestral to birds because they do not conform, in anatomy or lifestyle, to the true bird ancestor as imagined by these researchers. The theropod hypothesis of bird origins is not universally accepted. Credit: Yale University Press (left) Yale University Press (right) 'Riddle of the Feathered Dragons' is such a terrible (and terribly misleading) title. That section is reproduced here…Īlan Feduccia's books are by far the best known sources for the 'Birds Are Not Dinosaurs' arguments. Back in 2012 I wrote a long chapter on the evolutionary history of birds ( Naish 2012), and I thought it would be remiss to exclude a section on the BAND movement. It’s made “among the most interesting” by the fact that its proponents have seen themselves as crusaders, true sceptics and better scientists than those who support what is now the mainstream model they’ve – I think unwittingly – moulded themselves into a distinct social group, even going so far as wearing special badges at conferences. But… I can’t help but be interested in ‘non-standard’ or ‘alternative’ hypotheses on evolutionary history, and among the most interesting is the ‘Birds Are Not Dinosaurs’ (or BAND) movement. ![]() Additional support for the coelurosaurian origin of birds arrives on a regular basis, since new Jurassic and Cretaceous fossil species that fit somewhere on the bird lineage are reported virtually every month. A huge quantity of evidence shows that birds are dinosaurs, and specifically a lineage of the coelurosaurian theropod group Maniraptora.
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