Head, neck, and shoulder therefore all suggest that pterodactyls evolved from a primitive dinosaur, and so does the ankle joint. All dinosaurs had a hinge-like ankle that allowed the foot to flex foreward and backward relative to the shank.(animatronic dinosaur) But the dinosaur bird type of ankle didn’t allow the foot to twist much, so dinosaurs couldn’t turn the soles of their feet inward as can monkeys, most infant humans, and very agile human adults. Pterodactyls had an identical basic plan in the structure of their ankles. (life size dinosaur for sale)Crocodilians and their kin have a bent ankle-hinge line and so did most Triassic uncles of the dinosaurs (the thecodonts).
Reconstructing the ancestry of a clan like the pterodactyls remains an especially difficult challenge. Flying dragons seem to burst into the world like Athena from the mind of Zeus, fully formed. (dinosaur factory)Even the earliest skeletons of pterodactyls already display fully developed wings and the specialized torso and hips so character istic of the entire order. Cases like this in paleontology – and there are many more – persuade many scholars that evolution doesn’t work slowly and continuously at one even pace.
Instead, there appear to be times when evolution speeds up and suddenly produces totally new adaptive configurations.(realistic dinosaur costume)Pterodactyls must have emerged in one of these creative spurts of the evolutionary process. (realistic animatronic dinosaur)As of today, no fossils have been discovered to show how the pterodactyl’s forelimbs became transformed into wings. But the S-shaped neck, the simplified shoulder structure, and the bird-type ankle are excellent clues to the ultimate ancestry of the dragons—the quick and agile early dinosaurs of the Triassic Period.