why do animals have shorter lifespans than human beings?

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I’ve had several pets die of old age, and I found this very interesting, think about it, out of all the animals on Earth, only a select few can live for more than 70 years (the average lifespan of a human being).

In: Biology

2 Answers

Anonymous 0 Comments

Animals bodies wear out faster due to faster metabolisms and smaller sizes. Their bodies have to work harder and faster. Larger animals tend to live longer because they have slower metabolic rates

Anonymous 0 Comments

It’s a combination of a couple things.

* It depends a lot on reproductive strategy. Many animals have a lot of kids at once, so as long as more than a few survive, the species will continue, so there’s not a strong pressure for them to keep mating and they’ll die soon after to not compete against their own offspring. Humans, conversely, put a lot of energy into raising a tiny number of children, which means the parents have to stick around long enough to have multiple children one-at-a-time. It’s a quality-over-quantity thing, but quality takes time.
* Humans, because we walk upright and also have such huge heads, need to effectively be born premature in order to fit our brains through our mothers’ tiny birth canals. That means we’re helpless when we’re born, meaning it takes even longer for us to fully mature.
* We’re social animals. Our elders aren’t competition, they’re an extra pair of hands to gather food for as long as they’re strong enough to do so. They can still help their children and grand children survive well after having passed on their genes, which helps select for genes that let you live a long time.
* We’re fairly large animals in the grand scheme of things. Our metabolisms necessarily have to be slower so we don’t cook our own flesh as a human-sized mouse would. That also makes us grow and age slower. We’re also hearty enough to survive multiple winters.