The OTHER Aye-aye Dinosaur

Epidendrosaurus ningchengensis, like Scansoriopteryx after it, has been called an aye aye-like like dinosaur because of the elongated third finger of the hand. The actual aye-aye, Daubentonia, is a peculiar Madagascan lemur with a middle finger (index) greatly elongated and extremely thin with a small claw on the end, while the other fingers, as in all other lemurs, monkeys, apes, and us, has a nail instead. This finger is used to probe crevices for grubs and other food inside trees and fallen logs. Thus it is a specialized feeding adaptation. As I mentioned when I submitted Scansoriopteryx, these animals may not have been extremely flexible, and unlike the lemur, the wrist, elbow, and shoulder were likely very limited in movement. It seems odd, if not improbable, that these animals used their long third fingers to probe for food. Instead, they may have functioned like the middle finger does in non-winged dinosaurs, which has a great deal of motion and, along with the pollex (or first -- thumb -- finger) and the short third finger, would have been used to hold and grip, so that all claws faced into what ever it was holding on to. Here, the second figner may have supported feathers, and as such would have been almost incapable of moving enough to manipulate food, which may have neccesitated the long third finger's abilities.

Some have suggested these two animals are the same thing. It's possible, and they are very nearly the extact same size, with Epidendrosaurus about 5% smaller on average than Scansoriopteryx. Nonetheless, they also appear to be different in some features, as in the longer parietal in the skull (almost the same length as the frontal in Epidendrosaurus, but apparently much shorter in Scansoriopteryx), and the different shapes of the skull bones that are known. Otherwise, they might be clones.