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Re: Haplocheirus does not confirm alvarezsaurs are maniraptoran



 Enough grousing... _Haplocheirus_ is a really, really interesting
 critter.  It would seem that the peculiar functionally monodactyl
 manus of derived alvarezsaurs evolved *after* the forelimb had
 reduced in size.  This is strange, because if the forelimbs were used
 to rip open insect nests (either mounds or soft wood), why was the
 reach of the manus *decreased*?  This goes against the playbook of
 extant ant-eaters.

Ant-eaters don't need reach. (They can just walk closer.) They only need power.

The trick is that all extant ones are (to varying degrees, but still) quadrupedal. To be useful in locomotion, forelimbs need a minimum length. Compromises result that the bipedal alvarezsaurids simply didn't need.