(Evolutionists Only Please) Is there anything about evolution you think is wrong?

I don't think there is anything "wrong" with it, especially with the generality of the idea of descent with modification.

There are however a lot of things we don't know. For example:

1) Is geographical isolation a necessary step in the formation of species or is natural selection strong enough to counter the homogenizing effects of gene flow?

2) Are genomes cohesive or can portions of the genome be exchanged between emerging species?

3) How does selection act on genome structure at a large scale?

4) How do new genes arise? What is the role of gene duplication in this process?

5) Is there such a thing as convergent genetic evolution?

These are just a few, I could go on and on.

Notedstrangeperson said:

There is more genetic variety between people of the same race (and ethnicity) than there is between people of different races.

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Could you perhaps show this? I'm interested.

Notedstrangeperson said:

I believe genetic variety has little to nothing to do with creating new species. Instead it just makes different versions of the same species. I think new they might arise by "switching on" a particular set of genes.

I first thought of this idea after looking at human races. There is more genetic variety between people of the same race (and ethnicity) than there is between people of different races. So in theory two people from England would eventually become different species ... but English and Nigerian people would remain part of the same species. Obviously that doesn't make sense.

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Genetic variation has everything to do with species diversification. You are asking the question without looking at natural selection. So, let's elaborate in your example, correct me if I am wrong, but here is what I got as being your key assumption:

1) There is more genetic variation within the same race as there is between races.

Let's assume this is correct, which is not the case in humans but might very well be in other animals. So, your assumption is that because there is more variation in people from England (as opposed to Africa), they would become a new species. That, however, is not the case, as genetic variation per se is not the sole cause of speciation. If have to add selection to the mix. So, let's add second and third assumptions:

2) Selection pressure is different in England and Africa.

3) There is limited migration between England and Africa.

So, with the selection component added we can actually start talking about speciation. To simplify things, let's assume that because of the amount of solar radiation received in England and in Africa, it is highly advantageous to have light skin in England and dark skin in Africa. Now, regardless of how much genetic variation there is in both of these populations, they will be pushed apart by selection on skin color. See where I am getting at? Genetic variation is needed to provide the raw materials, but selection is the force that drives fixation (or extinction) of characteristics.

My personal belief is that humans, particularly, evolved from the pongo clade and are closer related to orangotangs than chimps.

There has been some research and a bit of controversy over this, I am happy to say and am excited and look forward to a definitive answer in the coming future.

Huram Abi said:

My personal belief is that humans, particularly, evolved from the pongo clade and are closer related to orangotangs than chimps.

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DNA shows you to be conclusively wrong.

Notedstrangeperson said:

I believe genetic variety has little to nothing to do with creating new species. Instead it just makes different versions of the same species. I think new they might arise by "switching on" a particular set of genes.

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Generally, species arise from multiple genetic changes in separated populations.

I first thought of this idea after looking at human races. There is more genetic variety between people of the same race (and ethnicity) than there is between people of different races.

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This is either right or wrong, depending on what you mean by it. Most genetic variation can be found within a race (or other human population), and the overall differences between the races are fairly small. But the typical European is more similar genetically to another European than he or she is to an African.

So in theory two people from England would eventually become different species ... but English and Nigerian people would remain part of the same species. Obviously that doesn't make sense.

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No, that doesn't make much sense.

We've even identified a particular gene which might be responsible for speciation: PR-Domain containing 9 (PRDm9). It's responsible for changes in genetic hot-spots - which in some cases can render male animals sexually incompatible with members of their own species. I suspect this gene is passed on the same way colour-blindness is - through the female line.

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It's one of several known speciation genes.

Notedstrangeperson said:

Approximately 85−90% of genetic variation is found within these continental groups, and only an additional 10−15% of variation is found between them. In other words,

90% of total genetic variation would be found in a collection of individuals from a single continent, and only

10% more variation would be found if the collection consisted of Europeans, Asians and Africans.​

- Nature.com​

By far the largest amount of that variation, about 85%, is among individuals within local national or linguistic populations, within the French, within the Kikuyu, within the Japanese
...
Of the remaining 15% of human variation, between a quarter and a half is between local populations within classically defined human “races,” between the French and the Ukrainians, between the Kikuyu and the Ewe, between the Japanese and the Koreans. The remaining variation, about 6% to 10% of the total human variation is between the classically defined geographical races that we think of in an everyday sense as identified by skin color, hair form, and nose shape.​

- Raceandgeonomics.ssrc.org​

The analysis, which is based on hundreds on hundreds of genes in scores of populations, shows that around eight tenths of the total diversity, worldwide, comes from the differences between the people of the same country: two Englishmen, say, or two Nigerians. Another five to ten per cent is due to differences between nations; for example, the people of England and Spain, Nigeria and Kenya. The remainder - the overall genetic differences between 'races' (Africans and Europeans, for example) - is not much greater than between different countries within Europe or within Africa.​

- The Language of Genes (Revised Edition, 2000)
Steve Jones​

Some people have used this fact to argue that human races technically don't exist, but I disagree.


Again, I just want to point out this is about exploring any thoughts you have about evolution - not necessarily proving an idea right or wrong.

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Yes, I get that, and the basic reason for that is quite simply because humans migrate a lot, so the genetic variation gets spread throughout the populations. But again, that has little to do with which populations will become species. As far as we know, in animals (let's not go into plants and micro-organisms for simplicity) there are only two main ways in which one species can split into two:

1) If populations become separated by a physical barrier that stops migration between them.

2) If selection pressure is different enough between populations to drive some alleles to fixation (or extinction).

So, it doesn't really matter where the genetic variation is (if within or between populations), what really matters is how (and most importantly how often) this genetic variation is crossing population boundaries. In our case, because we move a lot, there is a lot of gene flow, that is why variation within populations can be higher than variation between populations. But even if the variation in England is 100x higher than that in Nigeria, the two populations won't become species unless there is differential selection pressure or a cessation of migration.

Notedstrangeperson said:

Sfs: I know my idea doesn't have a lot of evidence behind it, it was just a thought. Are there any ideas about evolution you think are wrong or disagree with? You used to be a geneticist didn't you?

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Unless my boss knows something I don't, I'm still a geneticist. (I used to be a physicist.) There are specific positions held by some biologists that I disagree with(*), but I can't think of anything that is widely accepted that I think is wrong -- not surprisingly, since ideas have to be pretty well supported to become the consensus view.

(*) For example, there is a trend right now to downplay the importance of positive selection on new mutations as a force shaping current genetic diversity in humans, based on a paper in Science last year, and searching for instances of recent positive selection seems to be out of fashion at the moment. I believe that study placed only quite weak limits on the amount of recent positive selection, and that the fashionable view is premature at best.

I note, by the way, that there was a review on PRDM9 in the December issue of PLoS Biology, under the heading "Unsolved Mystery".

Phred said:

DNA shows you to be conclusively wrong.

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How so?

Notedstrangeperson said:

CabVet: For most of human history, the majority of people did not travel over long distances. We've only been doing so for the last few centuries, thanks to inventions such as aeroplanes, trains and the discovery of new continents. There have been barriers stopping us from doing so (oceans, deserts, mountain ranges etc.) and there are different selection pressures for different places - European climate favours fair skin while African and Australian climate favours dark skin.


Sorry to keep dodging your posts but I wanted to collect opinions from other evolutionists, rather than discuss what causes speciation.

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Ok, so now the subject is not speciation anymore, but the maintenance of genetic variance. We are confusing two things here, one is genetic variance and the other is similarity between two groups. A little genetics background:

1) Spreading genetic mutations in a population that is growing exponentially is incredibly easy, and that is what is happening to the human population in the last 2000 years.

2) All that it takes to maintain genetic cohesion between two populations is one effective migrant (a migrant that reproduces) per generation.

Do those two observations answer your questions?

Notedstrangeperson said:

We've had a couple of creationist-only threads, so here's one for the evolutionists - theistic or atheistic.

Is there anything about the theory of evolution you think is wrong or disagree with?

Just to clarify, this isn't about "disproving" evolution. You don't need to back up your ideas with evidence or refute an idea you don't agree with. These are just your thoughts.

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I believe genetic variety has little to nothing to do with creating new species. Instead it just makes different versions of the same species. I think new they might arise by "switching on" a particular set of genes.

I first thought of this idea after looking at human races. There is more genetic variety between people of the same race (and ethnicity) than there is between people of different races. So in theory two people from England would eventually become different species ... but English and Nigerian people would remain part of the same species. Obviously that doesn't make sense.

We've even identified a particular gene which might be responsible for speciation: PR-Domain containing 9 (PRDm9). It's responsible for changes in genetic hot-spots - which in some cases can render male animals sexually incompatible with members of their own species. I suspect this gene is passed on the same way colour-blindness is - through the female line.

Click to expand...

With a full and robust understanding, I don't see anything "wrong" with evolution, however, there are various places where there are competing theories which I have opinions on. Example, the pan spermia idea I largely reject. I very much doubt that any life would survive unprotected reentry. I'm more "membranes first" when it comes to origins of life.

Notedstrangeperson said:

We've had a couple of creationist-only threads, so here's one for the evolutionists - theistic or atheistic.

Is there anything about the theory of evolution you think is wrong or disagree with?

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You will need to explicitly state The Theory if you really expect rational responses to what is wrong with it.

The generic term really means a whole collection of ideas which included both evidence and the linking together of that evidence into deductions.

It is these deductions which are always slightly changing depending upon the particular State-of-the-Art of that moment.

Of course, you already know this.
You realize that BECAUSE of this recognition of the deduction part of Science we call our ideas Theories.

You know that science people admit that these theories can be reconsidered and even changed or amended in order to accommodate new evidence, or a different and better rationale.

One rationale I would change is the idea of what bible people call an absence of macro-evolution, or an absence of intermediary species between two different species that have been related by evolution, one evolving from the other.

It can be shown that evidence support a radical and enormous almost immediate transfiguration of one species into another.

Notedstrangeperson said:

We've had a couple of creationist-only threads, so here's one for the evolutionists - theistic or atheistic.

Is there anything about the theory of evolution you think is wrong or disagree with?

Click to expand...

Interesting topic.

Hmm. I wouldn't say I disagree with it, precisely*, but one thing I don't like to take for granted is that evolution is fundamentally the same on all scales. I guess it's part personal preference/gut feeling, part the early influence of Stephen Jay Gould, part thinking about the Cambrian explosion and early animal evolution in general. People always tell creationists that macroevolution is nothing more than lots of microevolution put together, but is that actually true? A related question, has the nature of variation changed over time?

*It feels like the more science I read and try to do, the less likely I am to have strong convictions about it. Reverse Dunning-Kruger effect?