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Anonymous File :-(, x)
>>297552
Genetic markers remain for tooth development in birds, but remains largely inactive. "Rare as a hen's tooth," as it were. But even the occasional "toothed bird" has a beak. Of course, I think we would have classified therapods as birds if they were alive today, so in a way, this thread is about a beakless bird...
The Hoatzin does have claws on it's wings, though... Quoted from some website:
Many features distinguish the hoatzin from other birds, not least of which is its voice which sounds more like a heavy smoker's wheezing than a bird call. About the size of a rather slender, upright pheasant, the hoatzin has an untidy crest of feathers, blood-red eyes encircled by bright blue skin, a long neck and long tail feathers. But perhaps the most interesting characteristic is the presence of claws on the wings and these, although useless to the heavy adult bird, are employed by the youngster to clamber among the branches near the nest- just as Archaeopteryx must have done so many millions of years ago.
The main function of the wing claws, it seems, is to assist the young hoatzin in times of crisis. The nest is normally built on branches overhanging water and is thus exposed to the eyes of marauding hawks. It is a rudely constructed platform of short twigs of roughly pencil thickness. If danger threatens, the parents usually abandon the nest for the safety of dense bushes nearby. The chick, left to its own devices, either uses the wing claws to help it clamber through the branches to some inaccessible spot, or dives into the water and emerges farther downstream to clamber back to 'the nest once the danger has passed.
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