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Marsdreamer t1_j9hniym wrote

Reply to comment by CletusDSpuckler in What are more accepted hypotheses that similarly explain the aspects of hominid evolution that the "pseudoscientific" aquatic ape theory does? by KEVLAR60442

Evolution is honestly a lot more nuanced than people generally realize. Even deleterious mutations and traits can rise to fixation in a population despite our understanding of fitness models.

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Somnif t1_j9i4ccm wrote

Also important to note that Evolution doesn't work towards the Best solution.

Just the... least worst.

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Marsdreamer t1_j9i7yo9 wrote

Pretty true. To kinda expound on that, it works "up," but it can get stuck on local maxima rather than global maxima. Picture two mountains separated by a valley and one being higher than the other. If a species is 'climbing' the smaller peak of fitness then once it gets there it can theoretically never climb down the valley and start climbing the taller mountain. It will always* be stuck on that smaller peak because Evolution doesn't know how to take short term pain for long term gain. It's effectively a greedy algorithm to borrow from a CS concept.

*As long as conditions stay exactly the same. The adaptive landscape is always changing.

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dmilin t1_j9iuy2i wrote

This is believed to be the reason no species ever developed wheels despite them being incredibly efficient. It's simply too large an evolutionary jump.

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chx_ t1_j9j0pkh wrote

Also, sorry for the amateurish questions, wouldn't that require a rotating axle which is kinda impossible to develop? Like, everything is connected to the rest of the body. Maybe some weird symbiosis could do it? :)

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RestlessARBIT3R t1_j9i7s2v wrote

Exactly. You don’t have to be the best at something, just better than anyone else around you

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viliml t1_j9itljd wrote

The least worst is the same thing as the best.

What you probably meant was "good enough".

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KJ6BWB t1_j9iip77 wrote

> Even deleterious mutations and traits can rise to fixation in a population

To be fair, it requires a lot for a new mutation to spread through a population. For instance polydactylism, or having more than 5 fingers on a hand, is a dominant trait but despite its advantages most of still only have 5 fingers on a hand because it's really hard for a new trait to spread unless it confers a real evolutionary advantage, meaning those who lack it die and most of the survivors have that trait.

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asdqwe123qwe123 t1_j9juz61 wrote

Dominance also has no effect on how common a trait is, with fitness levels being the same, an allele being dominant doesn't make it more present within a population.

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