I know the line between species is not even agreed upon but if we treated the human separation among groups of individuals as we do with other animals by those rules would different races be sub species?
The races as they’re usually referred to, certainly no. A European and an East Asian are closer genetically than a Bantu and a Pygmy, even though the European and East Asian would generally be referred to as different races, but the two Africans would be considered the same one. You might be able to divide modern humans up into genetic subgroupings that might arguably be called “subspecies”, but such divisions would be hard to justify and extremely fuzzy in any event. The whole concept of “subspecies” is vague to begin with, and most such examples are a lot more genetically different than humans are.
The definition of subspecies given by wikipedia is two populations that could inter-breed, but don’t due to some geographic or other barrier. As the Human races have been happily inter-breeding for quite some time, they don’t appear to meet this definition.
I guess 500 years ago, you could say that Eur-Asian-Africans were a seperate sub-species from Native Americans and maybe some isolated groups like the natives of the Tasmanian Island. Since then all those groups have inter-bred pretty enthusastically.
Isn’t one of the hallmarks of a different species that they can’t interbreed? By that definition, clearly not.
Human populations are not very genetically diverse compared to most species that are divided up into subspecies (though a ‘subspecies’ is, as Chronos said, pretty fuzzy). The genetic difference between any two human populations is very very small compared to the genetic difference between two individuals. Plus, today just about every human population interbreeds with other populations very regularly, so there’s no geographic or behavioural reason to separate populations as subspecies.
As noted in a recent thread in Great Debates, the current definition of subspecies requires abrupt changes in morphology. Humanity is clinal, meaning that each population blends in to all the surrounding populations. If we pick individuals from Oslo, Lagos, and Hong Kong, they are obviously different in appearance, but as we travel from Oslo to Lagos to Hong Kong by land, we do not find abrupt changes that distinguish one group from the next. Without those abrupt changes, we do not have a situation that supports the use of the word subspecies, (even if we could agree on what a race was or who was in any given race).
There have been earlier definitions of subspecies that might have supported the use of the word in relation to humanity, but we actually know more about the perceived “races,” (and more about genetics throughout the entire animal kingdom), than we did when those definitions were used, so the current definition–that excludes humanity from those species that have subspecies–is still the more accurate one to use.
Not necessarily. You can have, for instance, ring species in which the adjacent species can interbreed, but species at each end of the chain cannot interbreed. There are other definitions of specism as well that do not preclude interbreeding; see Ernst Mayr’s What Evolution Is as a pretty thorough explanation of speciation measures.
As Chronos, Simplicio, and Quercus have already said, the genetic variation across Homo sapiens sapiens is tiny even in comparison to most species, and the distinctions we make as racial characteristics are phenotypically less significant than the variations between most widely dispersed species. An obvious example of this is the American Black Bear (Ursus americanus) and the closely related Asiatic Black Bear (U. thibetanus) which show an enormous degree of variation of mass, coloration, and dietary and behavior habits across their wide ranges (virtually all of North America and significant portions of Southeast Asia, Eastern and Northern Asia, and the Japanese islands).
Race as a qualitative measure has only a very vague meaning, based almost exclusively on skin color, eye shape, and facial properties, all of which are relatively fungible; a pairing between an Asian male and a European female will result in offspring sporting mixing of “racial” traits. A mating between a Hispanic male and a Negroid female will give a skin color that is typically somewhere in between that of the parents. The estimation of “racial purity” by any quantitative means shows that any particular genetic biomarkers or traits that are typified by one ethnic group are generally highly dispersed throughout the population as a whole, with only rare exceptions like sickle cell anemia or rare blood subtypes which are restricted by virtue of inbreeding of geographically limited populations. Attempting to qualify racial variation by applying the scientific definition of subspecies will just result in an unworkable mess.
Stranger
I second the recommendation of Mayr’s book. It is brilliant.
This is a loaded question that has tended to draw out the “no, race is only skin deep” argument for the last several decades but more recent research indicates that there is more to it than that. Spencer Wells has done a lot of work on the Deep Ancestry gene project that hopes to show human migration patterns and development over time before they become even more hopelessly blurred than they already are. There are human populations with distinct genetic traits and it can easily be measured. You can have yourself added to the project and get the results back to show your rough ancestry for a nominal genetic testing fee.
The problem is that some of the biggest differences in human populations are not that intuitive. The African continent has always held the largest amount of human genetic diversity of anywhere on earth and many of those groups aren’t that related to one another despite sharing a dark skin tone. Likewise, the Australian aborigines are the most distant group genetically speaking from those in Africa because they migrated early but some of them look stereotypically black.
The current thinking is that only a few African groups migrated into Europe and then went on to become the Europeans and Asians of today while most of the other groups stayed in Africa. One of the groups that they founded became the Neanderthals and that may or may not be an answer to your question. The Neanderthals were once thought to be one of three known modern human species but it turns out that they may have been more like a human subspecies and never died out. Instead they, were genetically assimilated into other European and Asian populations thorough inbreeding. This idea has been around for a while but recent DNA research is showing that it did happen. Between 1% and 3% of European and Asian human DNA is Neanderthal in origin whereas this isn’t true for sub-Saharan African populations.
This is a nuanced question from many different angles. The definition of a species and subspecies isn’t nearly as well defined as it is usually given in a middle-school science book. There are also clear genetic differences between different human populations but they also blur and aren’t intuitive based on things like skin tone.
No, the hallmark is that they don’t interbreed in nature, not that they can’t interbreed. Many good species are completely interfertile in captivity. For example, all species of Canis (dogs, wolves, coyotes, jackals) and many species of ducks can produce perfectly fertile hybrids when they cross.
The Biological Species Concept (one of several possible concepts) requires that good species do not interbreed commonly in nature. Species that may be be capable of interbreeding are normally kept from hybridizing by differences in courtship behavior, ecology, time of activity, or other reasons.
Well, if we are too similar to be called subspecies, maybe we could instead be called breeds? Like the difference between a poodle and a german shepherd?
The thing is, all modern humans are all very closely related to each other. So while it could have been that there would be more than one human species, or subspecies, in actual fact this turns out not to be true. Or to put it another way, all other human species and subspecies are now extinct, and only* Homo sapiens sapiens* survived.
“Breed” implies artificial selection. Also, there are no clear-cut lines between human populations as there are between the breeds of domestic animals.
From Wiki’s page on subspecies
Humans fit the third case, and hence are regarded as a monotypic species.
According to previous concepts of subspecies, these were sometimes recognized where variation was clinal. However, even if you considered human populations before the Age of Discovery, when populations that had been somewhat isolated became globally dispersed, such a definition would require the recognition of dozens of human “subspecies,” since the clines for various characters (skin color, hair type, eye shape, skull proportions) are discordant; that is, they are not closely correlated with one another.
Doesn’t that usage right there mean that all modern humans already considered a subspecies (of H. sapiens)? Are there actually sub-subspecies?
That depends on how technical you want to get. In common usage, that would be a correct, if somewhat offensive term. In technical terms it is not really applicable as Colibri noted above. “type” or “morph” might be somewhat appropriate, but each have some specific issues as well. “Type” is probably the most appropriate.
Homo sapiens neanderthalensis is a trinomen for Neandethals, though I am not sure how controversial or not that designation is. Wikipedia is equivocal:
There is also another possible/probable *Homo sapiens *subspecies, Homo sapiens idaltu, that was discovered in 1997. I don’t know if the book is closed on that subspecies, either – they might (or might not) reclassify them as another species someday or end up declaring them Homo sapiens sapiens.
Back in the old days, my Culteral Antho Prof mentioned that the Ainu were a example of a people that may have been on their way to becoming a sub-species. There may well have been other isolated peoples that were on the path, but now that people move around a lot and cultural barriers are coming down, it does not seems like this will occur.
However, subpecies is a fuzzy term as Colibri sez, and it is not PC to use the term to refer to extant humans anyway.
No, we have to stick to the terms “populations” or “ethnic groups”, and those are many and varied, depending on the precise definition used. And, as was noted in the thread **Polycarp **linked to, human populations vary clinally, so there is never an objective place to draw the lines around these “populations” or “ethnic groups”.
There is no such thing as being “on its way” to being a subspecies. That’s sloppy science. Or rather, every population everywhere is “on its way” to being a subspecies as well as being “on its way” to being extinct. It’s a meaningless phrase, as it assumes a future that we can’t predict.