[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Gansus Bird-Dino Connection - Penn Press Release

Scott Hartman wrote:

Climbing hoatzin chicks aren't perching...at least while climbing.

Their parents have a strange form of perching. Aside from the anisodactyl feet, the sternum is also used to help support the body ("sternal perching"), probably because adult hoatzins are so front-heavy due to the huge crop.

Cassowarys are reported to occasionally scale trees, and I doubt very much that they perch.

I've heard that seriemas (Cariamidae) can do the same thing, and they use their enlarged inside claws. I didn't know about this behavior in cassowaries - but I also doubt that they perch. :-) However, humans are advised to climb a tree should they ever be chased by a cassowary, suggesting that the climbing abilities of cassowaries are not very good. ;-)

I've yet to see anything in the literature on *how* cassowaries and seriemas climb trees. Do they use branches, or the trunk, or both?

If a bird is arboreal without wrapping its toes around the branch I assume that would be a non-
perhcing bird. That said, I share Tim's general opinion that modern birds would have a difficult time being arboreal non-perchers.

Yes, that's exactly what I was driving at. Aside from Dan's examples of cavity nesters, that is.