Re: Deinonychus claws; love 'em or leave 'em

[Jonathon Woolf <jwoolf@erinet.com>]

Erik Omtvedt wrote:
> 
> I don't understand why people want to deny the obvious and make up all of
> these external excuses for the claw.  Deinonychus and velociraptor were
> killers.  Evolution would not give a devise for climbing--especially to a
> large animal--when the animal's main purpose was to hunt the ground
> feeders.  Besides, what good would a wolf-size predator do in the trees?
> Talk about the energy envolved to climb and then what would he do once he
> got up there?  Look people, the claws were for killing, not to climb up
> in trees to eat its kill like big cats, not to punture a hole in the prey
> and hope that it bleeds to death.  Carving, cutting, slicing, dicing.
> La la la la la.

First of all, leopards find trees quite useful for lookouts.  Leopards
have also been known to drop from trees to ambush prey -- it's rare, but
it's happened.  It's even been caught on film once or twice.  Leopards
also use tres to protect prey from scavenging hyenas and lions.

If "evolution would not give a device for climbing" to a large animal
(which _Deinonychus_ wasn't, as either dinosaurs or mammals go), how
much more puzzling is it to find a killing weapon on the _hind_ feet,
the walking feet?  That more than anything is what makes me doubt the
view you espouse.  _Deinonychus_ was bipedal,  with perfectly
serviceable claws on its hands and a mouthful of teeth that would make a
crocodile whistle in admiration.  In other words, it was an extremely
well-adapted predator without the foot-claws.  So, why add the
foot-claws?  It didn't need them.  Other theropods did perfectly well
without them.  They make no sense simply as added attack weapons. 
Therefore, it seems reasonable to look for a second function for them,
some context in which they do make evolutionary sense.  

-- JSW