Human Hybrid Gen1 Found in Russia :eek:

[Jokodo]

You don't understand, People of mixed race are less fertile, not couples of different races.
"hybrid vigor" is irrelevant here.

That's a claim that would need some factual support.

Im other words, did you just make that up?

No, I read about it long time ago. And it is not really that remarkable claim if you know how that stuff works.

It is remarkable enough. Your failure to see it as such doesn't make it less so. Also, what did you read about? Was there a discussion about potential explanations other than the one you seem to favor? I can easily imagine that interracial couples in the US have a lower number of children on average than either black or white couples, but that does not suggest a biological explanation and does jack shit to demonstrate an effect of hybridisation on fertility: it's sufficiently explained by the fact that conservatives tend to be more wary of interracial relationships, and also more in favor of big families. Occam's razor rings a bell?

 

[barbos]

No, I read about it long time ago. And it is not really that remarkable claim if you know how that stuff works.

It is remarkable enough.

Not if you have not failed high school biology.

Your failure to see it as such doesn't make it less so.

Failure is yours.

Also, what did you read about? Was there a discussion about potential explanations other than the one you seem to favor?

There was no need for a new explanation. Hybrid infertility is a known and understood fact, what they did is tried to measure for different human races and succeeded at that, effect is obviously small

I can easily imagine that interracial couples in the US have a lower number of children on average than either black or white couples,

You don't understand what hybrid infertility is, do you?

 

[Elixir]

People of mixed race are less fertile, not couples of different races.
"hybrid vigor" is irrelevant here.

Okay - source?

 

[Jokodo]

Not if you have not failed high school biology.

Your failure to see it as such doesn't make it less so.

Failure is yours.

Also, what did you read about? Was there a discussion about potential explanations other than the one you seem to favor?

There was no need for a new explanation. Hybrid infertility is a known and understood fact,

It is. Is it understood by you, though? Hybrid infertility is not a given between any two closely related populations. All extant humans are more closely related than members of the same subspecies in many other mammals, so we don't expect hybrid infertility to be an issue. Sure, it might, but that's something that would need to be demonstrated with solid data and by showing that alternative explanations are not viable. It is not something that can be assumed, nor something that trumps alternative explanations for an observed phenomenon as being more plausible, or as being idependently motivated.

what they did is tried to measure for different human races and succeeded at that, effect is obviously small

I'm not going to take your word for that. If you have a citation, let's look at the data.

I can easily imagine that interracial couples in the US have a lower number of children on average than either black or white couples,

You don't understand what hybrid infertility is, do you?

I do. However, another well known fact is that fertility-relevant behaviour (eg. use of contraception or lack thereof) is culturally transmitted from generation to generation. If it is indeed true that mixed-race individuals in a specific context (e.g. the US) show lower numbers of children than either blacks or whites, that does nothing to demonstrate a biological basis.

 

[Jokodo]

Maybe you're mixing it up with something different, [MENTION=224]barbos[/MENTION]?

There is indirect evidence that Neanderthal-modern human hybrid males may have been infertile. For example the fact that no Neanderthal Y-chromosomal DNA is preserved in any modern population could indicate as much, and as I understand it there is more suggestive evidence for that. But that says nothing about fertility of "hybrids" between any two extant populations.

 

[barbos]

Not if you have not failed high school biology.

Failure is yours.

There was no need for a new explanation. Hybrid infertility is a known and understood fact,

It is. Is it understood by you, though? Hybrid infertility is not a given between any two closely related populations. All extant humans are more closely related than members of the same subspecies in many other mammals, so we don't expect hybrid infertility to be an issue. Sure, it might, but that's something that would need to be demonstrated with solid data and by showing that alternative explanations are not viable.

It was demonstrated and explained.

It is not something that can be assumed, nor something that trumps alternative explanations for an observed phenomenon as being more plausible, or as being idependently motivated.

what they did is tried to measure for different human races and succeeded at that, effect is obviously small

I'm not going to take your word for that. If you have a citation, let's look at the data.

I can easily imagine that interracial couples in the US have a lower number of children on average than either black or white couples,

You don't understand what hybrid infertility is, do you?

I do.

It was a rhetorical question. You clearly don't understand the claim.

 

[barbos]

Maybe you're mixing it up with something different, [MENTION=224]barbos[/MENTION]?

There is indirect evidence that Neanderthal-modern human hybrid males may have been infertile. For example the fact that no Neanderthal Y-chromosomal DNA is preserved in any modern population could indicate as much, and as I understand it there is more suggestive evidence for that. But that says nothing about fertility of "hybrids" between any two extant populations.

No, I am not mixing it up with anything.

 

[Jokodo]

[MENTION=224]barbos[/MENTION]

citation or it didn't happen.

This is the science forum.

 

[barbos]

[MENTION=224]barbos[/MENTION]

citation or it didn't happen.

This is the science forum.

It did happen, I said so, you can cite me.
And yes, science forum requires more than constant nagging about citations, it requires certain amount of subject knowledge and understanding.

 

[Worldtraveller]

Well, this discovery rather gives fuel to the lumper side of the lumper/splitter conversation. i.e., if two species can have a viable offspring, by at least one common definition they aren't in fact two species but one.

Very cool discovery though. We'd already found a fair amount of evidence of DNA admixture between Denisovans, Neanderthals, and African human populations, but this case is quite straightforward.

Indeed. It's like the recent (a decade or so now) discovery that brown (aka Kodiak/Grizzly) bears and polar bears are not distinct species, but just 'races' that readily interbreed. I suspect that humans have always been horndogs and always will be. That alone would put in the lumper camp.

 

[barbos]

One wonders if she would have been able to reproduce, given that as I understand it, hybrids that we know of today are generally infertile.

What hybrid humans are you talking about? We're the last species standing, that is not in dispute. And we non-African humans have large segments of Neanderthal and Denisovan DNA in our genome, so at least some hybrid pairings must have resulted in reproductive success. There's only one way to inherit a gene.

That's not necessarily true. It is possible that Sapiens and Neanderthals mating could produce fertile offspring, that Sapiens and Denisovans mating could produce fertile offspring, but that Neanderthals and Denisovans mating could produce sterile offspring. Further that the Sapien/Neanderthal hybrid and Sapien/Denisovan hybrid mating could produce fertile offspring.

Ring species can result in some non-intuitive results.

Yes, ring species are very relevant here. They illustrate how hybrids become less and less fertile as two species become more and more genetically distant.

 

[barbos]

https://link.springer.com/article/10.1007/s00294-019-01038-x

Many species are able to hybridize, but the sterility of these hybrids effectively prevents gene flow between the species, reproductively isolating them and allowing them to evolve independently. Yeast hybrids formed by Saccharomyces cerevisiae and Saccharomyces paradoxus parents are viable and able to grow by mitosis, but they are sexually sterile because most of the gametes they make by meiosis are inviable. The genomes of these two species are so diverged that they cannot recombine properly during meiosis, so they fail to segregate efficiently. Thus most hybrid gametes are inviable because they lack essential chromosomes. Recent work shows that chromosome mis-segregation explains nearly all observed hybrid sterility—genetic incompatibilities have only a small sterilising effect, and there are no significant sterilising incompatibilities in chromosome arrangement or number between the species. It is interesting that chromosomes from these species have diverged so much in sequence without changing in configuration, even though large chromosomal changes occur quite frequently, and sometimes beneficially, in evolving yeast populations.

 

[Jokodo]

[MENTION=224]barbos[/MENTION]

citation or it didn't happen.

This is the science forum.

It did happen, I said so, you can cite me.
And yes, science forum requires more than constant nagging about citations, it requires certain amount of subject knowledge and understanding.

You have demonstrated neither.

 

[Jokodo]

https://link.springer.com/article/10.1007/s00294-019-01038-x

Many species are able to hybridize, but the sterility of these hybrids effectively prevents gene flow between the species, reproductively isolating them and allowing them to evolve independently. Yeast hybrids formed by Saccharomyces cerevisiae and Saccharomyces paradoxus parents are viable and able to grow by mitosis, but they are sexually sterile because most of the gametes they make by meiosis are inviable. The genomes of these two species are so diverged that they cannot recombine properly during meiosis, so they fail to segregate efficiently. Thus most hybrid gametes are inviable because they lack essential chromosomes. Recent work shows that chromosome mis-segregation explains nearly all observed hybrid sterility—genetic incompatibilities have only a small sterilising effect, and there are no significant sterilising incompatibilities in chromosome arrangement or number between the species. It is interesting that chromosomes from these species have diverged so much in sequence without changing in configuration, even though large chromosomal changes occur quite frequently, and sometimes beneficially, in evolving yeast populations.

I know what hybrid sterility/infertility is. Do you have evidence that it is an issue between any two extant human populations? Even in the sense that "hybrids" show a small but significant decrease in fertility that'll only become evident when you look at large numbers?

This doesn't qualify for the simple reason that it talks about yeast.

 

[barbos]

https://link.springer.com/article/10.1007/s00294-019-01038-x

Many species are able to hybridize, but the sterility of these hybrids effectively prevents gene flow between the species, reproductively isolating them and allowing them to evolve independently. Yeast hybrids formed by Saccharomyces cerevisiae and Saccharomyces paradoxus parents are viable and able to grow by mitosis, but they are sexually sterile because most of the gametes they make by meiosis are inviable. The genomes of these two species are so diverged that they cannot recombine properly during meiosis, so they fail to segregate efficiently. Thus most hybrid gametes are inviable because they lack essential chromosomes. Recent work shows that chromosome mis-segregation explains nearly all observed hybrid sterility—genetic incompatibilities have only a small sterilising effect, and there are no significant sterilising incompatibilities in chromosome arrangement or number between the species. It is interesting that chromosomes from these species have diverged so much in sequence without changing in configuration, even though large chromosomal changes occur quite frequently, and sometimes beneficially, in evolving yeast populations.

I know what hybrid sterility/infertility is.

No, you don't

Do you have evidence that it is an issue between any two extant human populations?

I read about it long time ago. maybe 15 years ago.

Even in the sense that "hybrids" show a small but significant decrease in fertility that'll only become evident when you look at large numbers?

Yes. effect was small. But it's linear.

This doesn't qualify for the simple reason that it talks about yeast.

It qualifies as illustration and explanation why it happens. Ring species is a good illustration too.

 

[Jokodo]

It qualifies as illustration and explanation why it happens. Ring species is a good illustration too.

That's not at issue though. You can't "illustrate" that the Sun has an iron core by pointing to evidence for Earth's iron core.

 

[barbos]

It qualifies as illustration and explanation why it happens. Ring species is a good illustration too.

That's not at issue though. You can't "illustrate" that the Sun has an iron core by pointing to evidence for Earth's iron core.

You can't illustrate your "point" with such a retarded analogy.

 

[Jokodo]

It qualifies as illustration and explanation why it happens. Ring species is a good illustration too.

That's not at issue though. You can't "illustrate" that the Sun has an iron core by pointing to evidence for Earth's iron core.

You can't illustrate your "point" with such a retarded analogy.

But you can "illustrate" that hybrid infertility is a thing between different human populations by citing a study on yeast? And how do I know whatever you read 15 years ago want also about yeast and you just remember wrongly if this is what you come up with?

I'm really hoping you quit your science job.

 

[barbos]

You can't illustrate your "point" with such a retarded analogy.

But you can "illustrate" that hybrid infertility is a thing between different human populations by citing a study on yeast?

Yes, because Meiosis in yeast and humans is exactly the same process.

And how do I know whatever you read 15 years ago want also about yeast and you just remember wrongly if this is what you come up with?

And how do I know you are capable of understanding whatever I link or post?

 

[Jokodo]

Yes, because Meiosis in yeast and humans is exactly the same process.

Remember the part you bolded? "The genomes of these two species are so diverged that they cannot recombine properly during meiosis, so they fail to segregate efficiently."?

That's not the case of any two extant human populations. At least, it cannot be assumed to be so, and is contrary to pretty much anything we know about human genomics. If you have evidence that it is, show it already.

Looks like you really don't understand the mechanisms behind hybrid (in)fertility all that well.