10 minutes ago, BusaDave9 said:

When compared to animals we are far more likely to pass on our genes to the next generation. 200 years ago people would have 8 children but most would not make it to adulthood. Wild animals have it worse than that.

Except, of course animals that produce dozens or hundreds of offspring each season, of course. Again, this comparison makes no sense.

6 hours ago, swansont said:

I will once again ask you for examples of evolution in humans

One example of human evolution that I've been thinking about lately is Lactase Persistence. All baby mammals drink milk. Lactose is hard to digest. Mammal babies make the enzyme lactase to digest milk. As the mammals grow they stop making the enzyme lactase. We humans have evolved to continue making this enzyme.

I wonder how this came about. Do you think this was natural selection? Do you think people drank milk, some died and no one made the connection until enough people died to evolve.

I don't know but I'll listen to opinions.

Just now, CharonY said:

Except, of course animals that produce dozens or hundreds of offspring each season, of course. Again, this comparison makes no sense.

True, in general, the larger the animal the fewer offspring. We'd have to do the comparison with other large animals.

I talked about this earlier and pointed out that spiders may lay hundreds of eggs at a time.

6 hours ago, swansont said:

I think a problem here is that you are narrowing your field of view on this, but still trying to apply it to a broader conclusion.. Avoiding predators is not the only avenue of natural selection.

Agreed. I have used examples of finding food and a broken bone is a death sentence for a deer or many other animals. I think the majority of the examples apply more to animals than humans.

Can you think of any examples of natural selection that affect humans more than animals. I realize there are lots of examples but I think living in the wild is harder than living in civilization.

7 hours ago, CharonY said:

This is again conflating survival with reproductive success.

I know the difference. I've talked about both. The post you quoted me I talked about natural selection.

Then when I talked about reproductive success I said "Next lets look at ..." as I changed the topic.

In wild animals I think the main driving force for evolution is natural selection but mutations must be present.

Do you think reproductive success is the main driving force for human evolution? I don't know but I don't think so. I think everyone can have a couple offspring. Since we have such a high survival rate people may decide to have 2 children, expecting both to survive. Animals have as many as possible without realizing the link between sex and offspring.

Is genetic drift the main driving force for human evolution? I very much doubt that.

Edited yesterday at 01:25 AM1 day by BusaDave9
to clarify

11 minutes ago, BusaDave9 said:

I wonder how this came about. Do you think this was natural selection? Do you think people drank milk, some died and no one made the connection until enough people died to evolve.

I don't know but I'll listen to opinions.

Research is good. Wikipedia or other free web sources provide a wealth of information on the nature of the LP gene, and consulting them would quickly make clear that it wasn't about people dying from milk consumption. Roughly 5 billion people in the world still lack the LP gene, and before 8-12000 years ago, almost no one had it. People who tried milk before then didn't die of flatulence and diarrhea, they just felt sick and decided milk wasn't a viable protein source. As do billions still. (Unless having access to lactose free diary products, as is common now in developed countries) Look up the topic and learn how selective advantage might have arisen for those having the LP phenotype - I gave you a strong hint a couple sentences back there.

Also note that at least six mutations (single-nucleotide polymorphisms – SNPs) have been associated with lactase expression. Can you see how these mutations might shift from being neutral to beneficial in certain environments? Look back through the thread and I think you can put this together. And also, a courtesy of replying to posts is appreciated. Several here are going to some trouble to help the learning process.

Edited yesterday at 01:35 AM1 day by TheVat

7 hours ago, swansont said:

I will once again ask you for examples of evolution in humans

Breasts are an interesting example of human evolution due to reproductive success.

Sexual attraction is the main reason women have breasts from puberty to death. Sure breasts are used to nurse infants but that is a very small percentage of their lives.

Think about this: no other animal, not even apes, bonobos and chimpanzees, our closest relatives have breasts until they have a baby and start to lactate.

Guys love breasts. That's why women have them even when they are not lactating.

Guys look at breasts and think "I want to have babies with her!" and they are NOT thinking "They would be able to feed our baby nicely.

Okay but seriously, I don't think this plays a big part when we are seriously looking for a wife. When guys are young they are just out to have fun and are attracted to breasts.

8 hours ago, BusaDave9 said:

One example of human evolution that I've been thinking about lately is Lactase Persistence. All baby mammals drink milk. Lactose is hard to digest. Mammal babies make the enzyme lactase to digest milk. As the mammals grow they stop making the enzyme lactase. We humans have evolved to continue making this enzyme.

I wonder how this came about. Do you think this was natural selection? Do you think people drank milk, some died and no one made the connection until enough people died to evolve.

I don't know but I'll listen to opinions.

True, in general, the larger the animal the fewer offspring. We'd have to do the comparison with other large animals.

I talked about this earlier and pointed out that spiders may lay hundreds of eggs at a time.

Agreed. I have used examples of finding food and a broken bone is a death sentence for a deer or many other animals. I think the majority of the examples apply more to animals than humans.

Can you think of any examples of natural selection that affect humans more than animals. I realize there are lots of examples but I think living in the wild is harder than living in civilization.

I know the difference. I've talked about both. The post you quoted me I talked about natural selection.

Then when I talked about reproductive success I said "Next lets look at ..." as I changed the topic.

In wild animals I think the main driving force for evolution is natural selection but mutations must be present.

Do you think reproductive success is the main driving force for human evolution? I don't know but I don't think so. I think everyone can have a couple offspring. Since we have such a high survival rate people may decide to have 2 children, expecting both to survive. Animals have as many as possible without realizing the link between sex and offspring.

Is genetic drift the main driving force for human evolution? I very much doubt that.

@CharonY did actually give a number of examples of environmental selection pressures that affect humanity, in response to a post of mine: climate adaptation, pathogen exposure and metabolic syndromes related to diet that reduce the chance of reproduction. (I might speculate in addition that tolerance to, say, certain pervasive pollutants in the human environment, such as oestrogen mimics, might confer a reproductive advantage.) Such factors are relevant measures of “fitness” in the Darwinian sense for humanity, whereas for example short sightedness arguably no longer is.

(This is important to understand. Darwinian “fitness” means suitability to the environment, not closeness to some standard of perceived physical perfection.)

One further interesting point he made in that post is that people with a genetic disability cannot be treated as if the disability is their sole contribution to the gene pool of humanity. They also contribute to the width of the gene pool in other respects, which may turn out to have evolutionary advantages at some point.

Edited yesterday at 09:48 AM1 day by exchemist

11 hours ago, BusaDave9 said:

Guys love breasts. That's why women have them even when they are not lactating.

It would help if you could reply to the posts responding to your question about lactase persistence. And do the homework that's needed to really engage with this topic.

13 hours ago, BusaDave9 said:

One example of human evolution that I've been thinking about lately is Lactase Persistence. All baby mammals drink milk. Lactose is hard to digest. Mammal babies make the enzyme lactase to digest milk. As the mammals grow they stop making the enzyme lactase. We humans have evolved to continue making this enzyme.

I wonder how this came about. Do you think this was natural selection? Do you think people drank milk, some died and no one made the connection until enough people died to evolve.

I don't know but I'll listen to opinions.

I’l lactose intolerant, as are others, so it’s not “we humans,” it’s “some humans”

It certainly could be that this ability persisted because dairy is a way to turn indigestible grass, etc. into useful calories, and that’s something that would give improved survival probability and increase the odds of passing down the gene(s) responsible

I asked for examples that supported your premise, i.e. ones that allowed you to draw your conclusion, and this doesn’t fit the bill. Evolving to adapt to new food sources is definitely something observed in wild animals.

12 hours ago, BusaDave9 said:

Breasts are an interesting example of human evolution due to reproductive success.

Sexual attraction is the main reason women have breasts from puberty to death. Sure breasts are used to nurse infants but that is a very small percentage of their lives.

Think about this: no other animal, not even apes, bonobos and chimpanzees, our closest relatives have breasts until they have a baby and start to lactate.

Guys love breasts. That's why women have them even when they are not lactating.

Guys look at breasts and think "I want to have babies with her!" and they are NOT thinking "They would be able to feed our baby nicely.

Okay but seriously, I don't think this plays a big part when we are seriously looking for a wife. When guys are young they are just out to have fun and are attracted to breasts.

Sexual selection. Definitely something that happens in wild animals.

Mammals generally have breasts, they just aren’t prominent when not lactating in most mammals. My understanding is that it’s part of the evolution of the human reproductive “strategy” where women aren’t just fertile for a short period of time (estrous) - humans don’t have a breeding season. Lots of inter-related elements in this. The specifics are human-centric but the process is not.

Your examples don’t support your thesis.

I wonder where the word mammals comes from.

There were mammals 66 million years ago, long before there were any humans.

Breasts are a spurious argument.

Here is a proposal I think worthy of consideration.

I suggest the main difference between humans and their evolution and other creatures and their evolution is that humans are generalists and very very adaptable.

Many, if not most, other creatures tend to develop (evolve) specialist traits and characterisation not possessed by humans or by many other creatures.

3 hours ago, studiot said:

Here is a proposal I think worthy of consideration.

I suggest the main difference between humans and their evolution and other creatures and their evolution is that humans are generalists and very very adaptable.

Many, if not most, other creatures tend to develop (evolve) specialist traits and characterisation not possessed by humans or by many other creatures.

Agree. I think the specific series of changes humans underwent is specific to humans, but the overall process is the same as all organisms, as it must be.

More specialized traits leave a species susceptible to extinction if/when the environment changes

3 hours ago, studiot said:

Here is a proposal I think worthy of consideration.

I suggest the main difference between humans and their evolution and other creatures and their evolution is that humans are generalists and very very adaptable.

Many, if not most, other creatures tend to develop (evolve) specialist traits and characterisation not possessed by humans or by many other creatures.

That is an interesting point. Generally speaking, specialist species tend to do develop within stable environments. The reason is that under unchanging conditions, there are certain optimizations (e.g. resource use) that provide relative fitness benefits (e.g. moving towards a set of fixed maxima in a fitness landscape). Generalists are more commonly found in changing environments, as optimizations do not provide the same fitness benefits. Humans are a bit different as they extend their generalist ability by being able to create fairly static habitats. I.e. they are not necessarily genetically as generalist as other species, but I would argue that their optimization of traits related to higher brain functions allowed them to expand the concept adaptability. Some other species do similar things, but not at that scale.

4 hours ago, TheVat said:

It would help if you could reply to the posts responding to your question about lactase persistence.

Thanks, that was interesting but to be honest I haven't really done any research beyond reading what you've posted. Maybe I'll find time after work.

4 hours ago, swansont said:

Your examples don’t support your thesis.

My thesis is that natural selection does not affect modern human evolution as much as with wild animals. You want examples? If I found few examples of human evolution due to natural selection and lots of examples of animal evolution would that be what you want?

I'm just interested in the conversation. I see lots of people surviving even with major genetic deficiencies such as blindness and deafness. I believe animals with these same problems would never reach reproductive age.

I realize people with genetic disability "also contribute to the width of the gene pool in other respects". That's true but they also pass on blindness and deafness.

20 minutes ago, BusaDave9 said:

I'm just interested in the conversation. I see lots of people surviving even with major genetic deficiencies such as blindness and deafness.

This is again shows a focus on the wrong elements. You should instead ask, do folks with blindness and deafness have higher or lower reproductive success than those without. This is the actual basis on how fitness is being calculated (the relative ability of a genotype compared to another).

Surviving is not the key part of the equation. And again, you can only compare reproductive success within species not between.

IOW, what you are interested in engaging with is more like a narrative discussion (similarly like would Godzilla win against King Kong) but it is not based on evolutionary science.

I've mentioned this several times in several ways but the OP seems uninterested in the bald fact that nearly have the human lifespan is beyond the reproductive stage, unlike most other creatures and life forms.

So they are only considering the contribution of half an average human's total.

3 hours ago, BusaDave9 said:

My thesis is that natural selection does not affect modern human evolution as much as with wild animals.

Yes. You also said the evolution that happens in modern humans isn’t due to natural selection.

3 hours ago, BusaDave9 said:

You want examples? If I found few examples of human evolution due to natural selection and lots of examples of animal evolution would that be what you want?

Yes, I want examples that support your thesis. I’ve asked for this multiple times. The examples you gave do not support your thesis.

3 hours ago, BusaDave9 said:

I'm just interested in the conversation.

I am too, but also not having time wasted by a bunch of tap-dancing

3 hours ago, BusaDave9 said:

I see lots of people surviving even with major genetic deficiencies such as blindness and deafness. I believe animals with these same problems would never reach reproductive age.

And I will ask again: so what? How does that tie in with your thesis?

What it shows is that specific pathways of and traits affected by evolution differ between species. You seemto think it has more significance but resist in explaining further.

3 hours ago, studiot said:

I've mentioned this several times in several ways but the OP seems uninterested in the bald fact that nearly have the human lifespan is beyond the reproductive stage, unlike most other creatures and life forms.

So they are only considering the contribution of half an average human's total.

Correct, I am uninterested in the bald fact that nearly half the human lifespan is beyond the reproductive stage. I don't care if they lived to 105 years old. All that matters is if they pass their genes off to the next generation and that usually happens when someone is in their 20s or 30s.

48 minutes ago, swansont said:

You also said the evolution that happens in modern humans isn’t due to natural selection.

I believe natural selection is not as prevalent in human evolution as in animals.

I don't think I said "evolution that happens in modern humans isn’t due to natural selection" but if I did I misspoke.

51 minutes ago, swansont said:

I want examples that support your thesis. I’ve asked for this multiple times. The examples you gave do not support your thesis.

If I found few examples of human evolution due to natural selection and lots of examples of animal evolution.
This would take a huge collection of evolutionary data to say natural selection is less prevalent in humans. Is this a scientific publication or an internet forum?

51 minutes ago, BusaDave9 said:

This would take a huge collection of evolutionary data to say natural selection is less prevalent in humans. Is this a scientific publication or an internet forum?

This is a science forum, which requires some sort of supporting evidence for assertion. A single (scientific) publication that would outline or even hint at it would be a sufficient basis for discussion. Yet so far we only have your belief. Even worse, it is pretty clear that you fail to understand the basics of it, specifically why a) you cannot group all animals into one big category and b) you cannot compare selective pressures between species meaningfully. And by ignoring these issues you just revert to repeat your assertion. Even worse, the arguments you present are not even inherently consistent. You somehow want to link lack of natural selection to a certain genetic syndromes and disabilities. For that to even start to make sense you would need to provide some evidence that somehow those factors do not in fact affect reproductive success (and this is likely again down to the fact that you conflate the ability to survive with likelihood of producing fertile offspring).

That being said, there are plenty of examples of human evolution over the last few thousand years and I have yet to see any evidence that this has somehow stopped.

In contrast, there are studies using population data, such as the Framingham study (a long term cohort on cardiovascular health) which suggested that some folks had children earlier lower cholesterol and some other effects compared to models where selection was not a factor (Stearns was the lead author in PNAS, probably around 2010s). The issue I had with these and relates studies is that it struck me as a bit improbable to find these effects in such a relatively short time frame. But the paper exists. I believe there were more studies using another population coming to similar conclusions I believe. I am sure since then there is more out there. I remember that natural selection was considered to be factor of different variations of metabolic syndromes, for example, and potentially with increasing sequencing results folks are able to test it.

What you are doing is to take assumptions and wildly extrapolate them. I see less disabled folks surviving, hence there is no natural selection anymore. This line of reasoning, is disconnected to the mechanisms of evolution (which I very superficially tried to introduce, and which is getting ignored).

Also the fact that we have more data on animals vs humans is not evidence. It means a) there are more animal species than human species and thus more researchers in the field working on various aspects b) animal models are more accessible for experiments. c) it is just very tricky in humans (it is also tricky for broader analyses in animals, but often there is something specific that one can pick out).

6 hours ago, BusaDave9 said:

I haven't really done any research

This is my shocked face 🥱

1 hour ago, BusaDave9 said:

I believe natural selection is not as prevalent in human evolution as in animals.

How much international warfare do animals engage in? Do animals ever practice genocide on continental scales? Do you not consider the various ancestral genetic ratios found around Europe of hunter-gatherer, to agriculturalist, to pastoralist evidence of evolutionary change? Do you not think that capital punishment over the millenia caused shifts in genetically based propensity for violence, burglary, or being Welsh in the wrong place at the wrong time. Do you not think that enslaved sections of society may not have been 'domesticated' to a certain extent in much the same way as aurochs became cattle, wolves became dogs etc? Or are you just going to glibly dismiss these as examples of 'unnatural selection' to save yourself the bother of thinking about them?

1 hour ago, BusaDave9 said:

I believe natural selection is not as prevalent in human evolution as in animals.

I don't think you're using the term 'natural selection' the way an evolutionary scientist would, and that may be leading to the confusion.
The 'environmental forcings' that humans are naturally selected for, are vastly different than those of wild animals.
We can regulate temperature of our environment, change our food supply, etc., but we have social forcings, economic forcings, etc. which most animals don't have.
As @CharonY tried to explain, comparison of the mechanisms for the two isn't really possible.

As another monkey wrench into the works, consider that humans are 'evolving' to outlive our reproductive age.
This is likely due to the economic forcing I mentioned, and we are not having enough children to replace the population.
I think @TheVat previously mentioned this, but eventually, in most advanced societies, the population will consist of a non-reproductive population due to its age.
That goes against the purpose of 'natural selection', reproducing, does it not ?
Maybe the mechanism of evolution doesn't like what we're doing, and is trying to kill us off.

1 hour ago, CharonY said:

there are plenty of examples of human evolution over the last few thousand years and I have yet to see any evidence that this has somehow stopped.

I never once said human evolution has stopped. This is a lie. As I have indicated before, I will not respond to people that lie about what I have said. I am looking for an honest discussion. If you are wrong, I don't mind. If you lie I will not respond.

14 minutes ago, MigL said:

The 'environmental forcings' that humans are naturally selected for, are vastly different than those of wild animals.
We can regulate temperature of our environment, change our food supply, etc., but we have social forcings, economic forcings, etc. which most animals don't have.
As @CharonY tried to explain, comparison of the mechanisms for the two isn't really possible.

It goes even beyond that, in a "not even wrong" kind of situation. Natural selection is, by definition, a relative force acting on a gene pool (be it species of population). It causes certain genotype to be relatively more or less successful than others. However, if we compare species, we are looking at entirely different gene pools and the comparison makes absolutely no sense.

Let's assume a population where there are literally no selection (or any stochastic parameters) except for one. Perhaps the ability to eat fast. In any other scenario it wouldn't be a meaningful fitness benefit, but in an otherwise entirely flat landscape, this would be the singular driver (imagine the only peak in an otherwise entirely flat landscape).

If you investigate it, it will look like strong selective pressure as it seems that the gene pool single-mindedly drives towards that trait.

Conversely, a different species might have a much more complex environment, so the same trait is also there, but kinds of drowns among all the other forcings. How would one compare this relative shifts to each other? At least AFAIK there is not simple calibrant that one can use to be able to compare that to each other.

26 minutes ago, sethoflagos said:

How much international warfare do animals engage in? Do animals ever practice genocide on continental scales?

Good points. Let me answer. Animals do selectively go after specific prey, eliminating them wherever they can find them. You talk about "genocide on continental scales" but only humans populate every country in the world.

When some animals try to kill every one of a specific species, do you call that genocide?
Sure you were talking about genocide within the human race. Many animals try to kill off an entire species whenever they encounter them. But you don't call it genocide when a species tries to kill another species.

34 minutes ago, MigL said:

We can regulate temperature of our environment, change our food supply, etc., but we have social forcings, economic forcings, etc. which most animals don't have.
As @CharonY tried to explain, comparison of the mechanisms for the two isn't really possible.

We don't need to compare the evolutionary mechanisms between animals and humans. We only need to compare the results. Because we can control our environment, we and control our food supply and our survival. The vast majority of modern humans survive for these reasons.

14 minutes ago, BusaDave9 said:

I never once said human evolution has stopped. This is a lie. As I have indicated before, I will not respond to people that lie about what I have said. I am looking for an honest discussion. If you are wrong, I don't mind. If you lie I will not respond.

My bad, I should stated "selective pressures in human evolution has stopped". The examples later including analysis of the Framingham study were specifically regarding detecting signatures of natural selection in very recent times (which, again, is exceedingly difficult). So IOW there is evidence of NS in humans over the last thousands of years, and some data on very recent events. So far, I have not seen anything that convincingly suggests that they are now suddenly one except your repeated assertions. Combining it with the issue that the comparison that you are suggesting is largely impossible (at least the way as it is stated, and with the caveat that I am not well enough read in the modeling aspects to know whether there might be a theoretical way to do so), are you going now to reconsider your initial assumptions or are we stuck on repeat?

23 minutes ago, CharonY said:

My bad, I should stated "selective pressures in human evolution has stopped".

Again you are lying. You put it in quotes so I searched to see if I misspoke. No, I never said that.

If you lie, lie, lie. Don't be surprised if I don't notice if you eventually do tell the truth. I will be ignoring your posts from here on out.

Edited 19 hours ago19 hr by BusaDave9
grammer

11 hours ago, BusaDave9 said:

This would take a huge collection of evolutionary data to say natural selection is less prevalent in humans. Is this a scientific publication or an internet forum?

It’s a science forum; kind of a hybrid of both. You’re expected to support your claims with scientific evidence.

Your response here suggests that you did not come to a conclusion and that this is a conjecture, i.e. speculation, which still requires evidence per forum rules. However, you have shown resistance to posts saying you are incorrect. The reasoning you use is limited to a few specific cases, which is cherry-picking. Not very scientific at all.

9 hours ago, BusaDave9 said:

I never once said human evolution has stopped. This is a lie. As I have indicated before, I will not respond to people that lie about what I have said. I am looking for an honest discussion. If you are wrong, I don't mind. If you lie I will not respond.

Not in this thread, but did express that sentiment before. A thread entitled “Are we still evolving?” and the first thing you say in it is “I say no” (a thread that covered much of the same ground as this one, showing that you’ve learned very little in 12 years)