Re: "Flight theory has legs"

["Jaime A. Headden" <qilongia@yahoo.com>]

Graydon (oak@uniserve.com) wrote:

<<<force limit; you can't apply more than will start shoving the
dromeosaur away from the prey.>>>

Jim Cunningham wrote:

<<Yes, you can.>>

<Ok, yes, there's the springing away phase.>

  Not involving the "initial physicial contact" phase. Reads like a
strategy card game....

<<Applying additional force will tear through the prey with more vigor,
just as it moves the predator away from the prey with more vigor.>>

<Not if the other two toes touch, and not if the claw rotates out of a
slicing angle and into a holding angle.>

  Especially if the other two toes touch. Of course, this is all one good
reason why jaguars can't get tapirs from above, they keep knocking the
tapirs away. [That was sarcasm.] A leap from above causes the prey to
collapse below it, but not force the predator away from the prey. The same
impetus will cause in a lateral or diagonal trajectory to carry the
predator with the prey, not "bouce off." Especially if the prey is of the
same relative mass as the prey.

<Well, if the predatory stroke with the feet is directed down, you have to
jump up to apply it to large prey.  (Small prey you're effectively
stepping on.)>

  The same slash "stroke" (arm or otherwise) will be just as efficient for
any given prey mass.

<This presumably starts with leaping and slashing, but you're better off
if you can extend the leap and pick _where_ to slash a little better. But
since your feet are off the ground, you have to use aerodynamic means to
add energy to get that 'hang time' in the leap.>

  Inertia. Falling causes inertia and potential energy to build. That is,
speed and time falling translates to kinetic force when the falling body
*stops* falling. This force transfers into the object that it hits when it
stops falling, like a game of marbles. Typically, the original falling
body must alter its direction to dissipate the remaining kinetic energy
and for struggling animals, this usually gets resolved with a jump "off"
after primary contact. At this point, both prey and predator are on the
ground, and the initial contact has resulted in a horrendous wound. Given
that the animals in question have large, powerful arms and many sharp
claws, it's easy to see an effective second stage attack as well.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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