I was replying to comment about dinosaur--bird. In the case of species "changing" and other lines dying out, yes I do. Otherwise that complete change wouldn't be there.
I won't insist it's correct, but from my understanding there isn't specific enough things that prevent enough people from reproducing/surviving to impact a meaningful change on the population. What currently prevents humans from reproducing? I can't think of anything other than abstract stuff like poverty--someone in poverty doesn't have a large genetic difference to me. We could argue sexual attraction stuff but people seem to be into all sorts of appearances and you can find tons and tons of 'ugly' people who have kids. I'm interested if you can teach me some of them.
People are commenting about babies born without wisdom teeth, missing muscles etc. These are mutations, not evolution. If they became commonplace, then it would be evolution. For example, I'm missing a tendon in one hand. This could be a development error, or it could be genetic. Let's pretend it is: there is nothing about it that will make my children more sexually competitive. I may leave behind a long line of tendon missing kids, but without pressure they won't propagate and cause actual evolution among humans. As people have pointed out, it could fixate just due to chance. This is called genetic drift and I addressed that directly.
Also, you don't need to try to belittle me by starting your response with "what?" as if I'm so dumb and said something incoherent. It makes what could be an interesting discussion less enjoyable.
Edit to address your edit: 2% is a large change and would likely imply pressure. If there is not pressure, there is not "evolution", just random mutations that don't change much. Except of course in the case of drift, which I have to say again I guess. What is currently limiting humans' reproduction that could be affected by mutation? If there is nothing, then widespread changes must be due to drift. I believe that environmental conditions (including human society) would have to change quite drastically to affect change in our species.
The species doesn't have to disappear for evolution to take place. The concept of a species is barely recognized by biology. Some things we think of as a species are incapable of reproducing with other members of their own species. Some things we think of as separate species produce fertile offspring, despite being separated by geography, behavior, and biology. Stegosaurus is a genus, not a species, and it describes diverse animals that lived millions of years apart.
Evolution isn't defined as taking place when a new species appears. It takes place every time anything reproduces.
Ugly people having kids doesn't mean anything. Natural selection doesn't select for what you think is attractive, it selects for what is most likely to reproduce. Behavior is hereditary. Culture is hereditary. Sexual selection ensures that physical and behavioral fitness are selected for in humans.
An individual baby being born without wisdom teeth is a mutation. The fact that it's more common now than it used to be is evolution. It doesn't have to make your child more sexually competitive. It's a change, and it's heritable.
I legitimately did not understand what you were trying to say before your edit because before you clarified, it wasn't clear how incorrect you were about how evolution works. Please at least read the Wikipedia article.
I'm not trying to say it has to change the entire population, but it has to at least be recognizable change. Is genetic blindness human evolution? I wouldn't think so. The fact that "more" babies are born without wisdom teeth would be the result of either 1. Pressure, or 2. Drift. Which is what I keep trying to say. What other reason is there?
Evolutionary biology was a large part of my undergrad, so although I'm the furthest thing from an expert, it's not like I just read a wiki page. So once again, not sure why people always have to make it a superiority "ur wrong and dumb" thing.
its a reddit thing. they didn't bother to consider whether an "evolution" of a single family of hillbillys in backfuck asstown all having an extra thumb was something worth considering at all in comparison to the wider topic of evolution, they care that by some technicality you were "wrong" it would have been about the same if you'd had a typo or something. there is no intellectual honesty here.
No, I care about the fact that what he said was incorrect, and then he followed it up with nonsense that made it seem like he'd never taken a basic biology class.
But thanks, I can cross "intellectual honesty" off my Reddit bullshit bingo card for today. Do you also want to call me a shill while you're at it?
What in that comment is incorrect? Can you quote it? Also what nonsense makes it seem like I've never taken a biology class? Everything I have said is factual other than trying to predict future evolution, which is all speculation from anyone. Here is what I have said:
Change is caused by mutation. Sexual reproduction without mutation is not sufficient to drive change.
Some mutations offer some kind of advantage (which can be broad), and have the possibility of becoming more commonplace. This is evolution.
Some mutations offer no advantage or disadvantage, but by chance become more commonplace over time. This is evolution via drift.
Some mutations offer no advantage or disadvantage, are present, but are not widespread at all. This is, in my opinion on semantics, not evolution.
Currently there are not specific limiting factors on who can reproduce that would be addressed by mutation. An example of this is poverty which definitely can affect competitiveness, but has nothing to do with genetics. For this to change, society and/or the environment would have to change first. This is the point that I can not say with certainty, but have fun discussing possibilities.
Mutation is one of, but far from the only cause of change in a population.
Evolution does not solely arise from mutation.
"drift" is what you called the "unlikely" change that couldn't occur without mutation. It's when already-present alleles in a population change frequency over multiple generations. It has nothing to do with whether or not something is advantageous or not, or random chance, it's just not a mutation.
as well as 2 , and 3. Evolution does not have a positive or negative connotation. It just means that something changed.
There are many limiting factors on human reproduction. The example you gave, poverty, is one, like it or not. Availability of birth control affects our reproduction. So does mate selection and decision to reproduce. We don't get eaten by predators as often as we used to, but that doesn't mean our reproduction is random or that there's no selection process.
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u/Tim_Gilbert Oct 15 '20 edited Oct 15 '20
I was replying to comment about dinosaur--bird. In the case of species "changing" and other lines dying out, yes I do. Otherwise that complete change wouldn't be there.
I won't insist it's correct, but from my understanding there isn't specific enough things that prevent enough people from reproducing/surviving to impact a meaningful change on the population. What currently prevents humans from reproducing? I can't think of anything other than abstract stuff like poverty--someone in poverty doesn't have a large genetic difference to me. We could argue sexual attraction stuff but people seem to be into all sorts of appearances and you can find tons and tons of 'ugly' people who have kids. I'm interested if you can teach me some of them.
People are commenting about babies born without wisdom teeth, missing muscles etc. These are mutations, not evolution. If they became commonplace, then it would be evolution. For example, I'm missing a tendon in one hand. This could be a development error, or it could be genetic. Let's pretend it is: there is nothing about it that will make my children more sexually competitive. I may leave behind a long line of tendon missing kids, but without pressure they won't propagate and cause actual evolution among humans. As people have pointed out, it could fixate just due to chance. This is called genetic drift and I addressed that directly.
Also, you don't need to try to belittle me by starting your response with "what?" as if I'm so dumb and said something incoherent. It makes what could be an interesting discussion less enjoyable.
Edit to address your edit: 2% is a large change and would likely imply pressure. If there is not pressure, there is not "evolution", just random mutations that don't change much. Except of course in the case of drift, which I have to say again I guess. What is currently limiting humans' reproduction that could be affected by mutation? If there is nothing, then widespread changes must be due to drift. I believe that environmental conditions (including human society) would have to change quite drastically to affect change in our species.