Given that mutation occur because there is a change in the structure of DNA, in animals, for instance the predominant species who may have mutations that help them survive in the wild world, those could be the ones who pass it on to their offspring. In my mind mutations are only transfer between generations if there is an actual benefit that lead to that species living longer, survive, protect or even hide better.
But with humans, how mutations work? We are not been chased down, eaten by predators? In that scenario, where everyone’s offspring gets a copy of a DNA from their parents, how we as humans have developed through the centuries, how is DNA mutations are propagated more so that it takes over and then more people are born with that mutation? For example, babies being born without wisdom teeth, smaller pinkie toe.
In the scenario of wisdom teeth, i heard that humans used to chew raw meet or something like that and thus we used those wisdom teeth more, but how it became so that now babies are being born without it?
I hope i made myself understand, I’m wiring down this before going to bed and I could go to sleep before looking for an answer, and my brain is not braining atm.
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You confused passing a mutation and spreading. Mutation can be passed to offspring as long as parent won’t fail to breed and that mutations can lead to minor “bad” traits or neutral traits. Those mutations appear sometimes and stay or die out eventually. Beneficial mutations that give some beneficial traits in long term have to promote survivalibity of an individual eg lactose tolerance.
And no, not using something doesn’t necessarily mean it will disappear, also mutation are noticable in geological scale more than in historical so fact that we as a humans doesn’t loosen wisdom teeth in 3000 hears is just because it’s too short to happen and wisdom teeth isn’t “bad trate” enough to exist a pressure for loosing it
> In my mind mutations are only transfer between generations if there is an actual benefit that lead to that species living longer, survive, protect or even hide better.
That’s not quite right. Mutations transfer between generations, period. Well, not quite period, because the mutations have to reach the reproductive cells before they can be transferred and some mutations occur later in life and don’t necessarily reach the reproductive cells.
But ignoring that, mutations are passed to children regardless of their benefit or detriment. What you’re thinking of is the basic mechanism behind evolution of species by means of natural selection — a creature with a beneficial mutation is more likely to survive and have children than a creature with a detrimental mutation. After all, a mutation that almost instantly kills the creature means the creature won’t even survive to sexual maturity and won’t even have a chance to be passed down.
But a mutation that turns eyes blue instead of brown? That’s pretty neutral all things considered so the creature with that mutation won’t have any particular malus making it less likely to successfully reproduce. Most mutations are fairly harmless and get passed on all the time.
How natural selection relates to humans is an interesting question and one with a long, long history of horrific and monstrous people trying to force an answer (see: Eugenics).
Because of our social nature and utter dominance of this planet, “can survive to reproduce” is a fairly low bar all things considered, so we humans have a lot of things have have built up in our gene pool that might seem pretty undesirable, but even that isn’t as clear cut as you might think.
There’s a mutation called “sickle cell anemia” which causes all sorts of health problems. Except sickle cell anemia also results in a much stronger resistance to malaria. Is sickle cell anemia a beneficial or detrimental mutation? It depends on if you live in an area where malaria is common or not and whether the negative health effects are outweighed by the malaria or not. As we build up more medical knowledge and infrastructure to fight and eliminate malaria the mutation becomes more and more of a detriment because the environment in which it exists is changing.
There’s another mutation that severely weakens a muscle in our heads and results in a significantly weaker bite force than we would otherwise have. Is this a negative mutation? You probably shouldn’t think so, because it’s believed to be one of the key features that allowed hominids to develop the big brains that let us have this conversation.
>In the scenario of wisdom teeth, i heard that humans used to chew raw meet or something like that and thus we used those wisdom teeth more, but how it became so that now babies are being born without it?
Because we’ve reached a point in our societal and technological development that those without them aren’t more likely to die before reproducing, thus removing the negative pressure on the spread of the mutation.
Wow! That’s a really thorough explanation, it is clearer now that all along was the topic of natural selection and that some mutations may have no benefit nor negative consequences but all depending on the current environment the individual is living in. When comes to all of this stuff, I was always fascinated with how this process has changed our life for either direction. And who some mutations does not provide any higher survival rate, thus being massively spread to more generations.
Thanks
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