5 ms·
By far the most important reason dictating lifespan is evolvability - the ability to adapt genetically [0]. This has so great effect that it's easy to observe
by Isinlor 6y ago
By far the most important reason dictating lifespan is evolvability - the ability to adapt genetically [0].
This has so great effect that it's easy to observe even in a simple computer simulations. If you don't adapt and the environment is changing, then you go extinct.
Think about this sharks and how much their environment has changed since they were born. As a spices they will have a very hard time adapting to the changes we induce in the environment. While small animals that have lifespan in weeks, months or few years will be adapting a lot faster. E.g. in one generation of this shark a mouse will go trough up to 900 generations with up to 12 offspring in each generation.
This shark probably will go extinct and mice will thrive.
Interesting consequence of this effect is that our lifespan is most likely not dictated by any fundamental limitations of biological machinery to maintain us healthy indefinitely.
A lot more likely is that we are evolutionary designed to get old and die.
https://en.wikipedia.org/wiki/Evolvability https://en.wikipedia.org/wiki/Evolvability
- lostlogin 6y agoThanks you, nice link. The opposite side of this is biological immortality. This wiki has a good discussion. https://en.m.wikipedia.org/wiki/Biological_immortality https://en.m.wikipedia.org/wiki/Biological_immortality
- 46756e 6y agoI’m not educated on this topic at all, but wouldn’t birth rate be more relevant than aging? If this shark lives 400 years but has kids often, it could also go through 900 generations like the mice. Presumably if the environment isn’t favorable then the old members of the species would die off anyway.
- albertgoeswoof 6y agoThe older living sharks would use up resources that the younger ones need to thrive. So it’s way more efficient to get the older population out of the way sooner. The longevity of the Greenland shark, humans and other long living animals, is in spite of evolutionary pressure to reproduce, raise the next generation and die.
- jagger27 6y agoConsider that a litter of sharks born in year 100 would be very closely related to a litter sharks born in year 400. Imagine the same pair of sharks mate over that span of time, those siblings are even closer. To me, evolution is a very deep graph of descendants. The scenario you propose is a very wide and shallow graph. N.B.: I'm a layman on this topic as well.
- pizzapill 6y agoTo counter this a little, there is a jelly fish Turritopsis Dohrnii which is biological immortal. Those jelly fish and sponges (which can get very old too) are very, very old/successful species.