Originally Posted by JMS

belgian blue cattle. its a mutation that inhibits production of myostatin to produce more muscle. the cows dont necessarily survive "better," but theyre bred to exploit this mutation and produce more meat.

doesnt only happen with cows.



similar mutation in humans has been found:

http://www.msnbc.msn.com/id/5278028/

of course, people are already at work, trying to harness this power to use it at will for things like muscular dystrophy and body building.