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Re: about those claws
Makes sense to me, but then...
> From: Kevin James Dracon <firstname.lastname@example.org>
> To: email@example.com
> Cc: firstname.lastname@example.org
> Subject: about those claws
> Date: Thursday, October 02, 1997 8:14 PM
> Hello all,
> I hesitated in bringing this up (novice that I am) in hopes that an
> would mention it. Oh well.
> 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'
> second claw worked in this manner. When the animal ran and pulled one
> 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
> theory). This assumes, of course, that the dromie was hanging on and/or
> attacking with its mouth and hands.
> Well, that's my two neurons' worth. I expect the flames to start any
> time. Have a wonderful evening.