Oxygen is quite corrosive, and eventually it poisons the body's chemistry.
Their cells accumulate mutations as they divide over and over.
Nat selection has programmed them to die, to allow for turnover in the population.
NS has taken control of the death rate, to prevent population overshoot.
NS doesn’t care about old animals, because animals in nature don’t last that long.
Some genes rev the body up for short-term fitness, but have bad results in the long run.

        40 votes    View Results and Comments