Metazoa info

[Duke Guilmon]

I don't think any other bird's wing delivers thrust on both the up and down stroke. It does make you wonder what led to that. Of course other birds can hover and some there are that are as completely dependent on flight as are hummers. Swifts likewise have ridiculously small feet which make them only fit for standing on .. no hopping or stepping. Swifts are among the birds that can sleep in flight. Huh, just looked them up and found that swifts are the only bird classed with hummers. One would have expected swifts to be more closely related to swallows.

Yeah, this is true. I have always knew that swifts and humming birds only use their feet for perching. Maybe there might have been an animal that only hovered once in a while but would fly like a normal bird other times. But this is only my hypothesis.