Neil Young referred to it with, "It's better to burn out than to fade away" while Pete Townshend echoed the sentiment with the line, "I hope I die before I get old."
Both men (who are now getting on a bit) knew that as humans age our organ function deteriorates, our skin loses elastin and sags, our bones decalcify and become brittle and the neurons in our brains gradually die out. In short, we fade away.
But do all animals age before they die? And if they do, why has natural selection shaped us this way?