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

Re: Why did small dinos become extinct?

The hands of alvarezsaurids faced ventrally, not medially, based on Senter's 2005 study on _Mononykus_'s forelimbs (Paleobiology 31: 373-381).

Oh, yes -- but that's because the arms are fixed in a sprawling position. Imagine a bird with permanently spread wings.

I also like the alternative idea of alvarezsaurids being professional scavengers - using their stubby clawed forelimbs to rip into carcasses, gobbling up the yummy bits, and using their long legs to run away when a bigger predator came along. Having only a single big claw on each forelimb, sheathed in keratin, might also have decreased the risk of infection from a putrefying carcass.

Then I'd expect more of a cutting edge on the claw, and longer arms. Or simply sharp teeth. Alvarezsaurid arms had a very small range of motion (same paper); they had nothing but sheer power.

Besides, professional scavengers that can't fly are impossible, see *Tyrannosaurus*.