[phasma proeliator]

Okay - so as the size of the animal grows - the muscle mass required to maintain a set speed (regardless of animal size - 45 MPH for instance) grows.

But, is this a linear path or exponential? if the percentages are the same - how fast can an osterich run and what percentage of it's total body weight is leg muscle?

[knarf]

Beats me, but I'm convinced the cave drawings were done by kids skipping school ... smoking dope.

The pictures showing men hunting deer with javelins are actually poets exxercising their license to depict what's gonna' happen to 'em when they get home.

[fourdeuce82d]

is this a linear path or exponential? if the percentages are the same - how fast can an osterich run and what percentage of it's total body weight is leg muscle?

IIRC, the amount a force a muscle can exert goes up proportionaly with its cross-sectional area, but the weight goes up by volume- an animal four times as big would have muscles twice as strong, but would weigh 64 times as much. I think.

[Dawgsquat]

Good point. Cheetahs aren't bulky either.

[longshadow]

But, is this a linear path or exponential?

The simple analysis is that volume increases with the cube of the size (which is roughly proportional to mass, while strength scales with the square of the size. (strength actually refers to structural strength, but it gives you an idea of what happens)

So, the mass/strength ratio varies with the 3/2 power of size.

[mcook4]

It has nothing to do with muscle mass. It is bone structure of the legs that determines speed.