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Comment by MustardTiger | Hacker News Reader

>The paper is about species, not subspecies.

And my reply is about subspecies, and our refusal to apply the same standards we apply to other animals to ourselves. I do not understand your confusion.

>Humans do not meet the phylogenetic criteria which justifies the use of "subspecies"

We have greater genetic difference between races than ANY example of subspecies in existence. I am very aware that a large group of people have a political agenda in denying this fact. But no amount of "we can get rid of racism by pretending races don't exist" will change basic facts. DNA does not lie.

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Yes, my complaint is that you are highjacking an article on species differentiation in giraffes to talk about purported human subspecies.

No, we emphatically do not have that high of a genetic difference. Quite the opposite. The diversity in human genetics is relatively small compared to other species. For example, quoting http://www.nature.com/ng/journal/v27/n2/full/ng0201_155.html :

> The extent of DNA sequence variation of chimpanzees is several-fold greater than that of humans[1]. It is unclear, however, if humans or chimpanzees are exceptional among primates in having low and high amounts of DNA sequence diversity, respectively. To address this, we have determined approximately 10,000 bp of noncoding DNA sequences at Xq13.3 (which has been extensively studied in both humans and chimpanzees[1, 2]) from 10 western lowland gorillas (Gorilla gorilla gorilla) and 1 mountain gorilla (Gorilla gorilla beringei; that is, from 2 of the 3 currently recognized gorilla subspecies[3]), as well as 8 Bornean (Pongo pygmaeus pygmaeus) and 6 Sumatran (Pongo pygmaeus abelii) orang-utans, representing both currently recognized orang-utan subspecies[4]. We show that humans differ from the great apes in having a low level of genetic variation and a signal of population expansion.

I'll repeat that last line for emphasis: "humans differ from the great apes in having a low level of genetic variation"

The paper I linked to previously specifically compares the differences in DNA between chimpanzee subspecies to any putative human subspecies.

> We know that there is human geographical variation, but does this infraspecific diversity reach a threshold that merits the designation 'subspecies', as is true with chimpanzees[14]? ...

> The within- to between-group variation is very high for genetic polymorphisms (approx85%; refs. 16,17). This means that individuals from one 'race' may be overall more similar to individuals in one of the other 'races' than to other individuals in the same 'race'. This observation is perhaps insufficient[18], although it still is convincing because it illustrates the lack of a boundary. Coalescence times[19, 20] calculated from various genes suggest that the differentiation of modern humans began in Africa in populations whose morphological traits are unknown; it cannot be assumed from an evolutionary perspective that the traits used to define 'races' emerged simultaneously with this divergence[15]. There was no demonstrable 'racial' divergence. ...

> Race' is a legitimate taxonomic concept that works for chimpanzees but does not apply to humans (at this time). The nonexistence of 'races' or subspecies in modern humans does not preclude substantial genetic variation that may be localized to regions or populations.

DNA doesn't lie. Humans lie, or are mistaken. Please demonstrate that you are not mistaken, and tell us the source of your statement that "We have greater genetic difference between races than ANY example of subspecies in existence".

What are the two most distinct human subspecies, and what is their level of DNA similarity? How does that compare to the difference in chimp subspecies?

>Yes, my complaint is that you are highjacking an article on species differentiation in giraffes to talk about purported human subspecies.

I did nothing of the sort.

>No, we emphatically do not have that high of a genetic difference

Yes, we do. The genetic distance between Nigerians and Australian aboriginals is .176. This is greater than the distance between almost any subspecies ever tested.

>DNA doesn't lie. Humans lie, or are mistaken

Yes they do. And they will even deliberately misrepresent facts to present things the way they want them to be. Like looking at isolated segments of DNA and drawing conclusions based on that (your link).

Citation for the "0.176", please? There are many scoring functions for DNA similarity.

Citation for the same numbers for chimpanzee subspecies, please?

Also, which Nigerians do you refer to? Huasa? Ibo? Because I think you meant to say either Yoruba or Western Pygmy.

At least I give links so others can double-check my statements. I would laugh if your reference used 500 bases rather than 10,000, or used something under strong evolutionary pressure instead of something neutral like this study.

FWIW, I'll use the time to the most recent common ancestor as my scoring function. For chimpanzees, two of the subspecies started to separate ~1 million years ago: http://www.eva.mpg.de/documents/AAAS/Kaessmann_Extensive_Sci... :

> When the MRCAs of the two chimpanzee subspecies for which multiple samples were available were estimated, they were found to be 1,755,000 years (95% confidence interval: 915,000 to 3,660,000 years) for the central chimpanzees and 502,000 years (95% confidence interval: 270,000 to 1,010,000 years) for the western chimpanzees.

The most recent ancestry for humans is no more than 100-200,000 years ago, dating from Mitochondrial Eve. We've had about an order of magnitude fewer generations to diversify than the chimps have. (We reach puberty later than chimps, so our generations are longer. Also, it's much more likely that our most recent common ancestor, pre-1400, is more recent than mtEve.)

By that definition, chimps are more diverse than humans.

If human races (which clearly exist) are not genetically distinct enough to be considered subspecies, how about the inverse? Can you point out examples of animal species/subspecies that have races?

Are different dog breeds the equivalent of human races, for example?

In the post you replied to I pointed out gorilla (with three subspecies, two of which are Gorilla gorilla gorilla and Gorilla gorilla beringei) and orang-utans (with Pongo pygmaeus pygmaeus and Pongo pygmaeus abelii) as two species with recognized subspecies. I also earlier mentioned chimpanzees as a species with multiple subspecies. https://en.wikipedia.org/wiki/Common_chimpanzee#Taxonomy says there are four.

This uses the taxonomic definition of race, which http://www.nature.com/ng/journal/v36/n11s/full/ng1455.html says "Although 'race' and subspecies are usually treated as equivalent, some zoological taxonomists reserve the word 'race' for local breeding populations, with subspecies being geographical collections of populations that are similar or the same in the defining traits."

That same article is careful to point out that the taxonomical definition is different from the sociopolitical, "socially constructed" definitions used by humans when talking about themselves.

Concerning dogs, https://en.wikipedia.org/wiki/Dog#Taxonomy points out that it's unresolved if domesticated animals should be list as a subspecies, so that dogs are "Canis lupus familiaris", or if they are their own species, as in "Canis familiaris".

In either case, dog breeds are "artificial variants created by ... selective breeding", from http://vertebrates.si.edu/msw/mswCFApp/msw/taxon_browser.cfm... . The term "variety" has no formal definition in mammalian taxonomy. See https://en.wikipedia.org/wiki/Variety_(botany)#Other_nomencl... .

Many animal species have races (or sub-species).

Dogs breeds are not generally considered as different species despite it being impossible for many to interbreed (think chihuahuas and Great Danes). Isn't biology wonderful :)

Yes humans are more genetically similar to each other than some other species, but this has nothing to do with the question if there are different sub-species of humans or not. You can't answer questions about speciation like this.

Physical difference is not the same thing as genetic difference. Humans may subjectively look very different but genetically humans aren't very different. This is empiracle fact. Stop living in the 19th century.

Physical difference has nothing to do with the discussion. That is a complete red herring you just pulled out from no where. The empirical fact is that humans are genetically quite different. The genetic distance between human races is greater than many species, and virtually all subspecies distinctions made in the animal kingdom. Stop denying science because of a false belief that lying will somehow get rid of racism.

Humans have accumulated an enormous amount of genetic variation between groups in only a few thousand years? Citation needed.

http://www.nature.com/ng/journal/v36/n11s/full/ng1435.html

You can barely even discuss the facts much less publish them because of histrionic accusations of racism and eugenics. Also, it hasn't been a few thousands years, it has been tens of thousands of years at the low end.

>The average proportion of nucleotide differences between a randomly chosen pair of humans (i.e., average nucleotide diversity, or pi) is consistently estimated to lie between 1 in 1,000 and 1 in 1,500 (refs. 9,10). This proportion is low compared with those of many other species, from fruit flies to chimpanzees11, 12, reflecting the recent origin of our species from a small founding population13.

>In other words, approx90% of total genetic variation would be found in a collection of individuals from a single continent, and only approx10% more variation would be found if the collection consisted of Europeans, Asians and Africans.

>The pi value for Homo sapiens can be put into perspective by considering that humans differ from chimpanzees at only 1 in 100 nucleotides, on average14, 15.

> Clustering of individuals is correlated with geographic origin or ancestry. These clusters are also correlated with some traditional concepts of race, but the correlations are imperfect because genetic variation tends to be distributed in a continuous, overlapping fashion among populations.

I'm not sure how this supports your point. What species are separated by a pi value of 1 in 10000 or less?

http://hydrodictyon.eeb.uconn.edu/people/fry/MolEcol.pdf has a table of π for subspecies of the song sparrow (Melospiza melodia). The smallest value on that list is 0.00095 or 1 in 1052.

The next smallest values are 0.00171 and 0.00204 while the largest is 0.00800 .

For the rock pigeon (~12 recognized subspecies), π = 3.6E-3 (1 in 277) says http://www.chinabird.org/news/Science-2013-Shapiro-science.p... .

Mice (three main lineages) also have a larger value of π than humans, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2219490/ :

> This study allows us to compare patterns of DNA sequence variation in mice to patterns seen in humans, the only other mammalian species for which extensive population samples of DNA sequence variation have been obtained. Levels of variation on the X chromosome in mice are nearly identical to levels of nucleotide diversity at X-linked introns in humans (π = 0.07%; Hammer et al. 2004), although levels of variation on the autosomes appear to be roughly twice as high in mice (π = 0.26%: Table 4) as in humans (π = 0.11%; Li and Sadler 1991; Aquadro et al. 2001).

These are yet more examples which demonstrate that human genetic diversity, despite the many claims by MustardTiger, is not greater than "virtually all subspecies distinctions made in the animal kingdom".

>I'm not sure how this supports your point

Why not? What subspecies has more than 10% of the species wide variation? I can't find any. This is what I meant. Just to report facts you have to try to couch it in politically correct disinfo. "This will make it sound like races aren't real, even though the data clearly shows they are". Just like "we're 99.8% the same DNA!". Yeah, but most of that DNA is also the same as a banana's. What matters is the differences, not the basic requirements for life.

>What species are separated by a pi value of 1 in 10000 or less?

I said subspecies. I won't be able to continue this conversation unfortunately, "you are submitting too fast". HN doesn't seem to approve of discussion.

> What subspecies has more than 10% of the species wide variation?

So you're not saying that the racial differences are large in absolute terms of how many genes are different, you're saying that they're large relative to the low overall genetic diversity of humans? That might be true[1], but that's because the denominator for a relatively new species is small, not because the numerator is large.

Also to me, a layman, if only 10% of our intra-species genetic diversity is between races that sounds like a pretty good case for disregarding race in the vast majority of situations.

> I said subspecies.

You said "The genetic distance between human races is greater than many species, and virtually all subspecies".

[1] What are the numbers for canis lupus, giraffes, etc. so I can compare?

> The genetic distance between human races is greater than many species

Please back up that claim.

MustardTiger I sympathize with the points you are trying to get across (and the undeserved downvotes and careless replies you are getting). Just one thing though

> We have greater genetic difference between races than ANY example of subspecies in existence.

You went too far with that comment. I think I know what you're trying to say: that if intrahuman genetic divergence and superficial morphology differences were observed in any other organism it would be classified as subspecies, but as a matter of fact there remain many examples of strongly genetically divergent populations in nature that have not been elevated from subspecies to species, and some which are unlikely to be due to known introgression etc.

EDIT: yes I know that introgression doesn't contradict species status for many species definitions, but taxonomy literature is determined by practices local to the community studying the taxon in question and for many taxa introgression is still certainly an argument against classifying as species.

Yes, upon further research I see that you are correct. Thanks for the info.

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