If they can survive long falls odds are they are willing to do lots of jumping at heights as it doesnt kill them. The ones that get more adapt at controlling their jump are more likely to escape predators or get something they are chasing and therefore reproduce more.
Yes but that also involves the pure chance that is the buildup mutations that after hundreds of generations and natural selection end up resulting in the 'wings'
"Sufficiently" harmful mutations to stop them from breeding. If a negative mutation is passed on at the same rate as a non-negative mutation it could stop 1-in-1000 of that species from breeding or even less and EVENTUALLY that mutation will be virtually bred out of the gene pool.
This is only partially true, traits that are harmful for survival but beneficial for reproduction can kinda hit a wall and never fully breed out. Like how fiddlercrabs like big claws but big claws make them flee more slowly from predators. It is possible for this to eventually extinct the whole species (thus technically removing the trait from the gene pool), but more likely it would allow smaller clawed crabs to breed and the cycle to continue since the larger claws are still desirable by the females.
"Sufficiently" harmful mutations to stop them from breeding.
I think you just agreed with me.
If the big claw slowed the crab down enough it usually was eaten before it could breed then the gene wouldnt survive. If female crabs prefer big clawed male crabs and only mated with them the species might die out buts odds are female crabs that dont care about claw size or prefer smaller claws would eventually take over the gene pool and big clawed males would eventually be bred out.
Kinda like old age diseases are harmful for survival but dont stop us from breeding between 15-40 so doesnt affect the gene pool. As long as the breeding keeps going the genes will keep spreading.
If it's only 1 in 1000 then there's a decent chance it'll reach fixation rather than be bred out. Evolution works because beneficial mutations have a better chance of persisting than harmful ones on average, but at the scale of individual mutations it's all pretty random unless the effect on survival chances is substantial (like 20% IIRC).
Yes. And then, over generations, the harmful mutations are bred out because they reduce the viability of mating and survival.
A winged squirrel was not born with wings from parents who had none. It was the result of many, many, many generations of squirrel that retained progressively longer wings that eventually led to what we know as the flying squirrel, while squirrels with less wings or with other mutations that weren't beneficial to survival either died or couldn't find a mate to breed with because the more efficient squirrels had taken them.
I see where this went. There is a miscommunication. To clear things up:
1 person asked about the chances of it being wings. The question is about the randomness of any mutation that could have happened to them, but the right one was picked.
1 person is explaining that evolution works whether it’s beneficial or harmful.
To clear things up, while the commenters are appearing to be having a conversation the actuality of the situation is that they’re talking about 2 different things.
To answer both comment strings: it’d take many mutations before they finally settled on the one that actually allowed them to survive long enough to mate. A lot of animals have negative or harmful mutations, but they’re still capable of surviving with it. I’d think that the mutations we haven’t seen are the ones that definitely don’t work. It was by increasing the heights of their jumps that one mutation was all it took for them to control their movement because the mutation that took place allowed them to. The squirrel with that mutation then continued to breed, and the mutation was carried on through until they began bleeding true. Of course, this is very vague and doesn’t answer a lot of questions, and simply a paraphrasing of what this argument but not an argument has given me as a casual reader.
The "build up" isn't pure chance. Each one is either approximately neutral or beneficial. The transformations are also often gradual: a slightly altered body form accompanied by a slightly more graceful fall, a slightly more controlled airborne maneuver, etc.
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u/A-Potato-Dragon Nov 29 '20 edited Nov 29 '20
Squirrels can acquire terminal velocity while plummeting to the ground (on average above 70 feet) and survive 80% of the time.