by Marlowe Hood Agence France Presse PARIS, France (AFP) — It’s not quite E=mc2, but scientists unveiled Monday a simple, powerful formula that explains why some animals run, fly and swim faster than all others. Call it the “speed rule”: strength alone does not determine top velocity because land mammals, birds and fish can only accelerate for as long as they can draw from available energy stored in muscle tissue. An intermediate body size — […]