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RE:about those claws
> Birds have a special adaptation in their feet that allows them to perch.
> The tendons which control the toes run up the leg and are rather
> unelastic. As long as the bird keeps its leg extended, the toes can move
> freely. If the bird bends its leg, the toes flex because the distance
> between the origin of the tendon and the toes lengthens. This allows
> perching birds to sleep while perching. Suppose the dromaeosaurids' large
> second claw worked in this manner. When the animal ran and pulled one leg
> up, the second toe would flex and the claw would be pulled downward
> (someone mentioned that a dromie might disembowel itself if it kept its
> toe in the vertical position while running, made me think of this).
> When the leg straightened to contact the ground, the toe could be
> raised to the vertical position again to help prevent wear on the
> ground. Also,if the dromaeosaurid attacked something, it might leap and
> extend its legs in the air (allowing the claw to assume the "retracted"
> position), then when it struck the animal, the impact would bend the leg
> and for the claw downward and into the prey. With its initial momentum
> gone, the dromie would begin to slide down the side of the prey animal,
> dragging the claws (this would work better with the "all toes in the kick"
> theory). This assumes, of course, that the dromie was hanging on and/or
> attacking with its mouth and hands.
If you reconstruct the foot based on birds - tendons running from the
calf to the toes, then the toe claws will rotate down as they move the
foot forward with the leg bent. This is a great point. It implies that
the claw will stab into a tree or prey and allow lifting/supporting the
dinosaur,s weight with this claw. My opinion is that the hand claws did
the most damage. I would expect a little more shoulder muscle and
"popeye forearms" than shown on most restorations. Czerkas's models and
Rachel Clark's drawing "thistle" are the best with this musclature.