Why do some species live so much longer than others? Parrots live to be over 100 but mice only live 2 years. I feel that the person who can answer this might be on the way to telling us how to live forever!
They say that most animals have about a billion heart beats. Some animals have a much slower heart beat and animals such as mice have very fast heartbeats. While this is not and exact amount it does show how metabolisms may vary.
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