Well, go hungry.

E. elaborated a complex mechanism of protection as a species. And it is not ordered so Her Majesty Nature - not to establish such a mechanism, and that's all ... Our Earth has not experienced the least - what is this fauna. Maybe Flora would not know either. But we are just about the fauna - and, hence, about us with you. Probably all have seen, thanks to television broadcasts such as "in the animal world, as to earn their living prey, say, tigers or leopards in the savannah as they hunt antelope or any other livestock. Clearly seen when the show closeup - as predator screw up one's eyes as he raised the hair on the nape as he stops for a moment, as ... One word is preparing the body to an extraordinary situation - to hunt. Trigger the brain, the subcortical structures, in particular the pineal gland, starting in the enhanced mode to synthesize and release into the blood to adrenaline and acetylcholine, the adrenal glands. The famous American scientist-physiologist at Harvard University Walter Cannon (W. Cannon) identified and examined the physiological properties of the natural chemical transmitter of nervous excitement - simpatina E (from the English word exiting - exciting), later called noradrenaline and simpatina I (from the English word - inhibitory - inhibitory), called adrenaline. These studies led to the creation of H. Selye doctrine of the general adaptation syndrome. By the way, it was Cannon and called adrenaline "emergency hormone". And, in his opinion, this is the best emergency hormone performs in extreme conditions to mobilize all the forces of the body, all the functions of his survival. Increased excretion of (output) of adrenaline is always marked by emotional stress or pain, for any psychological and emotional overload. Survives aggression the state that ensures the timely mobilization of its forces, resources. For example, our country has managed in the 40's with a monstrous force of aggression by Nazi Germany mobilized its resources, its army, the people who managed to evacuate the factories to the east and begin production of modern weapons - tanks, aircraft, artillery, etc. And just because we then survived. Likewise, the body of an animal (including our bodies) survives, if it can mobilized its forces and resources. If the body is the same antelope, which attacked the tiger or leopard, healthy and able to provide a synthesis of the proper, corresponding to the situation of adrenaline, acetylcholine and other substances, the Antelope will be able to get out, escape, escape. And if not ... Then nothing can be done - go for lunch predator. Conversely, if a predator good adaptive mechanism - it will overtake the antelope and will fill it. And if not ... Well, go hungry. And if it persists - nature takes care of that this predator long roamed the savannah ... And so in nature always has been, is and will be. When we say that the fittest survive, then we have in mind not muscle strength (or rather not so much muscle) and strength and ability to mobilize the adaptive mechanism, worked out over millions of years.