The genetic differences between you and any other human being of any other race are vanishingly small both in proportion to the size of the human genome and to the (known) differences between sapiens and neanderthalensis.
It's not politics, it's parsimony.
It could become problematic if, as has been suggested, some or all of the other great apes are reclassified as Homo rather than Pan, Gorilla or Pongo.
For a layman, an "human" is a "modern human", i.e. "Homo sapiens sapiens", i.e. me.
There are two difficult problems here. The first is how to classify animals species (including humans, whatever it means). The taxonomy classification is somewhat arbitrary. It's very useful for discussions between biologist, but arbitrary.
For an easy example, what is a kingdom looks like an easy question, but https://en.wikipedia.org/wiki/Kingdom_(biology)#Summary
Currently Homo, Pan, Gorilla or Pongo are different "genus" of the Hominidae "family". (I hope I got all the notation correctly.) The genus is somewhat special, because it's written in the name of the specie, but we could have agree to write the family in the name two. We could have been "H. H. sapiens sapiens" and chimps could be "H. P. troglodytes"
The second problem is that we all agree that the sentence for killing a "human" should be different of the sentence for killing a cow or a pig. But the decision of what "human" means in that sentence is a political one, not a scientific one. Should we consider killing any great apes as bad as killing me? What about other apes? Why? Why must we use the taxonomy classification? What about whales and dolphins? Octopus?
Tangent, but if we ever genetically engineer some eldritch horrors, I vote to classify them as "H. P. lovecraft".
Technically a 'species' is something that interbreeds but does not breed with members outside of it's species and mating produces reproductive offspring. (at least this is the old mayr definition that everyone uses)
The problem is that neanderthals and humans matings produced viable offspring. So is 'neanderthal' a species or not?
The same issue is a problem with the Galapagos finches, which are the holy cows of darwinian genetics. By Mayr's definition they should not be able to interbred and produce viable offspring. However, apparently they can interbreed and therefore are not technically different species.
No one in science want's to badmouth the masters, so Darwin's theory of Galapagos finch species will quietly be put back in the Victorian cabinet while we invent a new 'genetics' based theory of 'species' that makes everyone happy. However, life is not easily classified. Viruses? Species? Bacterial plasmid replication?
There is a lot of politics in the life sciences. Naming a new species or having your name on a species is a big deal. It reminds me of Cope/Marsh and the dinosaur finds (https://en.wikipedia.org/wiki/Bone_Wars) of the early 20th century. They both screwed up the identification of many species so that they could out publish the other and left the mess for future scientists to clean up.
My feelings on this is that we still don't have enough evidence about the genetic makeup of humans to really make any conclusions on anything. Example: What is the blood type in the reference sequence for the human genome?? We know that there is A, B, A/B and O which represent 4 different genotypes (an AA sequence, a BB sequence, an AB sequence and a missing sequence from both alleles).
If I sequence a neatherthal with blood type A and a human with blood type O, are we genetically divergent?? How can you come to this conclusion unless you know the plasticity of each genome. (i.e. I can't identify a nucleotide change in blood type gene for a type O human because the gene is absent)
It looks like most of the research has been on mtDNA which is passed from mother to child. If we can't find a mtDNA match, it might just mean that there is no maternal linage that can be traced back to that sequenced individual. (i.e. all the children of that mother died out at some point)
Different species? That's a question for politics imho. I personally think that life shuns classification. BTW sorry for the ramble :0
Species and race are vague terms we use for convenience. That's all. I think keeping them vaguely defined is a feature not a bug, because it could help prevent people assigning too much weight or meaning to them. If people get the idea that race and species can be precisely defined, then maybe they can be measured? Maybe we can use that to derive tests or policies? But trying to precisely define race and species is futile, like trying to put light in a box. I'd rather knowingly and consciously keep the ambiguity, to remind myself that the terminology isn't the reality.
Similarly, the definition of species as individuals that breed with each other has importance for transmission of genes. By this rationale, transitive gene transmission makes ring species a "species".
A biologist told me that species are defined, not by theoretical interbreeding, but by actual breeding...so that a single species divided somehow in different environments, is now two species, even when no genetic change has occurred.
By this strange extrinsic definition, the human races were different species before global travel... and now are one.
And that SV hackers who only breed with other SV hackers, are a different species (and the rise in autistism incidence evidences a genetic effect - in a few million years, interbreeding will be impossible!). Similar for classes, the 1% etc.Though there is crossbreeding in practice, so at most these are ring species.
No, that is the best kind of ramble. Thank you for the interesting and thought-provoking comment!
Yes there is no one universally agreed definition of species, but Neanderthals were vastly more different from living humans than and differences between living human populations.
https://en.wikipedia.org/wiki/Congo_Pygmies
(Anatomic differences are perhaps not as important as cognitive and psychological differences, but the latter are very hard to find out about extinct populations.)
As far as I know there is no evidence that neanderthal females could produce fertile offspring with a male homo sapiens -- but only the other way round.
http://www.sciencemag.org/news/2016/04/modern-human-females-...
Two people from different races can be way more similar genetically than two people from the same race. The concept of race was built over a long story of separating humanity in different ethnic groups, and then physical characteristics of some of those ethnic groups started slowing being adopted as a mean to show that those people are intrinsically different, but they are just an unimportant set of characteristics that does not convey important information from a genetic perspective, they gained social meaning through culture. The modern concept of race took form in the enlightenment, https://twitter.com/Limerick1914/status/757227361582608384, when the original western notion of which ethnic groups exists in the world was built into a racist anthropology.
That doesn't mean that "all lives matter" or we shouldn't talk about race. Race is a social construct, and as a social construct, it exists. Money is also a social construct. But, the concept of race makes no sense besides the social structure that was built on. That why different countries consider that the set of existing races is different, for instance, the only country that really considers "latino" a race is the US.
Going back to your question, the extinct humans actually had important biological differences, the different races have not.
If humans and Neanderthals interbreed for a long enough period without annhiliating each other through war, wouldn't their offspring converge over time?
Some ethnicities are more susceptible to certain diseases. Is that a social construct?
We still, at least subconsciously, apply the "one drop rule" in all sorts of situations, including describing the race of the current US president. Sub-saharan Africa contains more genetic diversity than everyone else, yet we lump them all together in one "race."
Yes, there are distinct genetic differences between various groups of people, and many of those differences have real-world consequences. But the relation of those groups with what we call "race" is almost zero.
The everyday races correspond to real, observable genetic clusters. There are real characteristics shared by members of these large groups, e.g. the epicanthic fold in East Asians.
The genetic phylogeny doesn't lie. The Sub-Saharan diversity you're mentioning --- e.g., between Bushmen and the Igbo --- is about large-separation clades within the larger continental grouping.
This stuff does not line up neatly. To the extent that there are genetic differences between groups of humans, the dividing lines don't match our concepts of race.
Obviously not. But quoting Wikipedia[1], an average of 85% of genetic variation exists within local populations, ~7% is between local populations within the same continent, and ~8% of variation occurs between large groups living on different continents, whereas [a]pproximately 10% of the variance in skin color occurs within groups, and ~90% occurs between groups, which indicates that this attribute has been under strong selective pressure.
When defining human race, we hone in on a few easily identifiable characteristics that have remained stable due to selective pressure (eg skin colour) and overblow their significance. Eg we suspect that humanity went through a genetic bottleneck when it left Africa, decreasing diversity. And yet, we generally lump the rather diverse African population that did not go through it into a single race.
It's probably more useful to just look at specific genetic traits of interest instead of drawing somewhat arbitrary boundaries.
That's Lewontin's Fallacy [1]. There's no logical reason to think that genome-wide diversity within populations somehow proves that large-scale impactful allele frequency differences between conventionally understood races do not exist.
They do. You can measure them. Given someone's DNA, you can identify his content-scale race. (You can actually narrow someone's ancestry much more narrowly too. Race is a cakewalk.)
[1]:
http://onlinelibrary.wiley.com/doi/10.1002/bies.10315/abstra...
"In popular articles that play down the genetical differences among human populations, it is often stated that about 85% of the total genetical variation is due to individual differences within populations and only 15% to differences between populations or ethnic groups. It has therefore been proposed that the division of Homo sapiens into these groups is not justified by the genetic data. This conclusion, due to R.C. Lewontin in 1972, is unwarranted because the argument ignores the fact that most of the information that distinguishes populations is hidden in the correlation structure of the data and not simply in the variation of the individual factors. The underlying logic, which was discussed in the early years of the last century, is here discussed using a simple genetical example."
We can reliably identify haplogroups associated with certain phenotypes popularly categorised as "races", but we can also [more] reliably identify genetic markers associated with other phenotypical differences which have little or no correspondence with haplogroups. The presumption of greater significance of haplogroup-associated differences is the social construct here.
And of course, inevitably you move on to pretending that the huge and stable variation in measured test performance within a population is of lesser import than relatively small and unstable difference in average test performance between populations. Even if we grant the rather silly proposition that tests so unstable that the Dutch population improved by more than a standard deviation in thirty years are actually a good measure of innate intellectual differences unaffected by non-genetic factors, you've got the problem that it's impossible to predict with any degree of certainty what the person who took the test's genetic background actually is. I mean why would anyone interested in investigating innate intelligence choose to focus on genetic markers that predict my skin tone pretty accurately but can't even rule out the possibility of me being in the very top or very bottom percentile for results in any cognitive ability test?
I'm going to go out on a limb and suggest that if a test indicates that me and my fellow white English thirtysomethings produce average scores a standard deviation ahead of (i) thirtysomething black people living in my country and (ii) my white grandparents' generation when they were my age, what's actually measured by the observed one standard deviation average differences across cohorts probably isn't genetic differences....
And yes, some ethnicities being susceptible to diseases is a social construct because ethnicities follow the same shifting standards. Your talking about the intersection of an imprecise categorization with biological understanding that is only dependent on the latter to remain true. It's useful today because (in some societies) it can signal aspects of biology. But human societies in the future could have entirely different notions of race and ethnicity that change or renders the overlap meaningless.
Sad thing about humanity - we love to politicize facts and deny reality because it doesn't match some ideology.
You're accusing me of politicizing facts, but seeing race in and around normal human variation is itself a political act, even if it is an innate prejudice.
The idea that race is scientifically invalid is complete nonsense. You can argue that race doesn't correlate with phenotypical characteristics that we care about (okay, but it does though), but arguing that race itself is just in our heads is nonsense.
Is it any wonder that more and more people distrust science on issues like evolution, climate change, autism, and so on when scientists claim that you can't really tell whether someone is white, black, or asian?
[1] https://en.wikipedia.org/wiki/File:The_history_and_geography...
You couldn't be more wrong.
My mother is Puerto Rican, and my father is mostly Irish (with some ancestors from other European countries). My 23AndMe results show that all of father's genes are from Europe, and my mom's come from Europe (mostly Spain, but with a tiny bit of Ashkenazi), Africa, and the Caribbean (Native Americans, likely the Tainos).
My genetic makeup is roughly 7% Native American, 14% African, and most of the rest is European; some percentage is inconclusive.
You may be able to guess that I mostly look white, and you'd be correct. However, with my mother being roughly half non-white and half white, what would you guess? I'll tell you right now that I wouldn't guess that she's from Europe, but she does have relatively light skin. Her sister, however, could easily pass for a black person.
To think that your phenotype can be determined just by looking at your genes is ridiculous, and it's clear to me that you have very little experience in diverse environments. Things like skin and hair color are complex and are determined by multiple alleles, and there's no way to know which ones are going to be dominant.
Even aside from genetics, the social construct of race is even more complex, and I challenge you to do more reading on why that's the case.
Edit: To add more fuel to this, most of my girlfriend's genes come from China and surrounding areas in the Southeast. If we have a child, what will they look like?
Roughly 3.5% Native American, 7% African, 39.5% European, and 50% East Asian. Tell me, what race will they be? What about their phenotype? There's simply no way of knowing. Scientifically, race just does not exist.
You absolutely can predict someone's phenotype from her genotype, roughly speaking. In cases of recent admixture, the exact gene expression can be uncertain. Just look at Mendel and his peas! Even this variable heredity has limits. There was a zero percent chance that you'd end up looking like a typical Japanese person.
I don't understand your point. I'm not claiming that the classic races are fixed for all time. I'm not suggesting that we can't arrange genes in new combinations. I am claiming that people today cluster in certain historically-contingent ways and that these clusters reflect the everyday understanding of race.
As another commenter said, what about Obama? I've met people who are half black and half white and end up looking like white people. Obama doesn't look like someone from Africa, nor does he look like someone from Europe. Because of what society determines as being white, most people would say, "he looks more black," which isn't really true, but regardless, you likely would not be able to tell just by looking at his genetic makeup. Many people in the same circumstance look wildly different from him.
If your argument is that when someone's genes all come from one area, then you can take a guess at what they might look like, then sure. But to apply that blanket statement to the entire world is just not the case. There are parts of the world where those lines get very blurred (e.g. Turkey, Nepal, Afghanistan), and plenty of people who are of "mixed descent" with different phenotypes from you would predict from their genes.
In terms of population, things then average out. There are indeed parts of the world where things are very blurred because of extensive human interaction across populations. If every place in word were like that, then there indeed wouldn't be what we call races. But most of the world is not quite like that, and particularly, in the course of history it hasn't been.
For example: what race is the current President of the United States? Most would say "black" (or "African American" if they're trying to be politically correct). And yet his ancestry is half European.
This is hardly an isolated example. The average African American has about one quarter European ancestry. About 10% of African Americans have a majority European ancestry.
Yes, you can use genetics to divide up humans into related groups. But those groups will not match with how we divide up races.
Also, is it worth pointing out that the people who don't believe in climate change, think vaccines cause autism, think evolution and fossils are a hoax etc. could make your exact claim about how scientists not coming clean on their pet subject and rather intentionally misrepresenting the facts to the public for whatever nefarious reason makes it their own fault that no-one believes in science.
How do you convince yourself you're not one of them and therefore actually the cause of the very problem you lambast scientists for? I'm sure they have books with nice diagrams proving them correct too.
Let's define our terms. By "race", I mean the classic continental groupings of people whose ancestors come from areas centered on Europe and the near east, east Asia, and Sub-Saharan Africa. When we say "race", we're talking about that category to which people readily self identify and to which we can easily assign others. When we say "race exists", it means that these categories are not arbitrary.
More generally, they're big ancestor clusters. You can see the clusters yourself if you take genome corpuses and run principal component analysis (or other grouping algorithms) on them. If you select k=3, the classic continental races come out of the data.
I'm not sure how much more real a taxonomic classification scheme can get. We use the same genomic approach for organizing the rest of life.
With more groupings, you get finer-grained population clusters nested inside the larger ones. If you look for enough clusters, you start seeing an "Irish" grouping. Can we agree that, say, the Irish, the Italians, and the Slavs are distinct hereditary groups? Can we agree that they're more similar to each other than, say, the Irish are to the Pygmies?
You could, in principle, put everyone into her own cluster. Sure, at k=7e9, race doesn't exist. But that's not a very useful classification scheme, because it ignores the reality that there are high-level classifications that we can see with our own eyes.
> How do you convince yourself you're not one of them and therefore actually the cause of the very problem you lambast scientists for?
That's an excellent question. Epistemology is hard. The best we can do is try to explain observations using the best-predicting theories we can find. I reject the "race does not exist" theory because it fails to explain observable facts about the world. This theory requires, in order to explain our observations, elaborate systems of oppression. It's full of epicycles. Even so, it fails to predict the result of studies like the Minnesota Transracial Adoption Study.
The "race corresponds to allele clusters" theory makes better predictions. It explains heritable and persistent differences in measurable characteristics. It agrees with genomic observations. It requires no hidden assumptions. This latter theory isn't politically correct, but this status can't affect its truth value. We delude ourselves about things all the time.
Look: the traditional continental race classification scheme is a crude folk theory. It's very embarrassing for science when even a crude folk theory makes better predictions than the best theory to come out of the academy.
Eppur si muove.
Possibly you're just talking past each other, and don't fundamentally disagree at all.
When I say that "race exists", I mean that there are real differences between the k={3,4,5} groupings and that almost always tell someone's group affinity by sight alone. The existence of marginal cases doesn't somehow invalidate the reality and utility of the high-level groups.
When people say "race doesn't exist", the general public reads that as "there are no differences on average between people from the various continents", and this claim is not only false, but it's so false that one doesn't need sophisticated instruments to tell.
I believe that this confusion is deliberate and is part of a misguided attempt to eliminate bigotry by delegitimizing the classification schemes upon which bigotry is built. This strategy is doomed, because you can't take away people's eyes and ears.
I personally think of the concept of species, etc., as "shades of gray" that change depending on the lighting. (If that makes sense.)
Look at the huge differences in dog breeds, for example. If I didn't know better I would think some dogs are a completely different class of animal when compared. (Think chiwawas and german shepherds, in their visual appearance.)
Sometimes I think of my dog as a person. Other times, not so much. Is it political? I think some people could make some sort of (weak) argument for that; in how I allocate resources to my dog, and why I do it. Why I even keep a dog around.
Also depends on how you'd define politics; how broadly and deeply. In this case I think your question it's a very interesting one, if we were to imagine running into a fresh population of neanderthals I bet there would be political ramifications between groups!
In fact also some pure breeds cannot give birth except by Cesarean section.
Although if you have ever read the original Dune series... chairdogs.
It turns out the concept of species is dated or at least doesn't fit all the phenomena out there: http://biology.stackexchange.com/questions/39664/how-could-h...
So, I suppose one could argue to some extent that Neanderthals were a human race rather than a species of their own.
It seems political. Either some of the current races are different species, or the so called extinct human species are just different races.