Friday, December 07, 2012

Ian Cromwell Talks About Zombies and Racists at Eschaton 2012

I met many interesting people at Eschaton 2012 in Ottawa. One of them was Ian Cromwell who gave a talk about racism on Sunday morning. Ian thinks that the skeptic/atheist movement ought to pay more attention to racism and he made his point by teaching us how to recognize zombies and racists.

Ian has a degree in statistics and epidemeology from Queen's University (Ontario, Canada) and he now works in Vancouver (British Columbia, Canada). He has a blog called The Crommunist Manifesto on Freethought Blogs. His blog deals mostly with racism issues.

Here's a video of a recent talk he gave in Vancouver (Part 1 of 5).



I really enjoyed Ian's presentation except for one small comment he made. He said something like, "There's no meaningful distinction between human races." When I asked him about this after his talk, he seemed to defend the proposition that human races don't exist. The comments on his blog suggest that we could have a productive discussion about the meaning of the word "race." See: #Eschaton2012: some additional reflections where he says ...
The thesis statement of my talk: that skepticism can and should be applied to the topic of race, seemed to strike the crowd as pretty non-controversial, which was nice. The lion’s share of the questions in the subsequent panel went to me, suggesting to me that the topic of race is one that is underexplored but sorely wanted within the skeptical/freethinking movement. There was an exchange with Larry Moran after my talk was over that I anticipate will turn into a brief back-and-forth between our two blogs as we sort out the biological underpinning of race and what those mean in the real world.
My position is that the term "race" is used frequently to describe sub-populations of species, or groups that have been genetically isolated from each other1 for many generations. By this definition, races exist in humans just as they do in many other species.

The genetic evidence shows clearly that Africans form a distinctive, but somewhat polyphyletic, group that differs from the people living outside of Africa. Amongst the non-Africans, we recognize two major sub-groups; Europeans and Asians. I see no reason why these major sub-populations don't qualify as races in the biological sense. lease read: Do Human Races Exist?.

I don't think that denying the existence of races is going to make racism go away. Nor do I think that accepting the existence of biological races is going to foster racism.


1. Genetically isolated does NOT mean there's no gene flow between the groups. Is there was none, they would be different species. Please don't use the silly argument that the existence of hybrids disproves the concept of human races.

48 comments :

  1. I'm with Ian here. If Africans form a distinctive grouping, what distinguishes them? Genetically, they're all over the map. Morphologically, there is perhaps a matter of pigment, but even that varies in the rest of the world to about the same degree, and anyway it's a single trait subject to selection even in the presence of gene flow. The claims about Europeans and Asians are even worse.

    There's geographically structured genetic variation in the human population, but it's really hard to get from there to races.Usually in biology, we don't distinguish races if variation is clinal, as it is in humans and especially if the clines in different features don't match. Subspecies most commonly don't overlap in range, yet human distribution is continuous.

    ReplyDelete
    Replies
    1. Perhaps a lack of Neanderthal and Denisovan DNA?

      Delete
    2. There's nothing in the biology literature that says we can't have variation WITHIN races.

      If you look at trees constructed using different alleles (or haplotypes) you'll see that the European and Asian groups usually form monophyletic clusters. There really are differences that we can use to identify the main groups genetically.

      If you were handed DNA from ten Europeans, ten Asians, and ten Africans, it would be easy to identify the continent they came from. In fact, experts can do this with skeletons.

      It's true that subspecies (races) in other species don't usually overlap in range. It's also true that for most of the past one hundred thousand years there wasn't much overlap between people living in Africa, Asia, and Europe.

      Sure, there was hybridization at the boundaries of the ranges but this is also true of subpopulations in all other species.

      John, what about Neanderthals and Denisovans? Do you think they qualify as examples of human subpopulations (races)?

      Delete
    3. There's nothing in the biology literature that says we can't have variation WITHIN races.

      Which is probably why nobody has raised that issue. I am also currently doubting your claim that Asians can be reliably told from Europeans, or either from Africans. At least with Africa there's a geographical barrier of sorts. But the Urals are a poor excuse even for a mountain range.

      If there were a geographically restricted hybrid zone, that would be one thing. But where is that hybrid zone? Instead, we just get broad clines that don't match across loci.

      As for Neandertals and Denisovans, I suspect they do qualify, though we don't know that much about geographic variation, do we?

      Delete
    4. Well, people from the Middle East, India, Central Asia, North Siberia and even the New World seem to cluster with Europeans in many respects, rather than with Southeast Asians, never mind Native Australians or New Guineans. And of course there are clinal transitions between, say, India and Europe on the one hand, and India and SE Asia on the other. Attempts to define race consistently remind me of those desperate beaurocratic/police classifications like that used by the British Home Ofiice:

      White European (IC1)
      Dark European (IC2)
      Afro-Carribean (IC3)
      Asian (IC4)
      Oriental (IC5)
      Arab (IC6)

      Note that "Asian": in this strictly British sense means Indian ~ Pakistani ~ Bagladeshi, and that they sometimes have to use IC0 for "miscellaneous other" or "race unknown".

      Delete
    5. @john harshman:
      I am also currently doubting your claim that Asians can be reliably told from Europeans, or either from Africans

      Sigh... Ever heard of PCA? After at least five years of the barrage of papers pertaining to the genetic structure of human populations based on huge number of molecular markers, how can anyone keep repeating the old falsehoods with a straight face? How can you?

      FYI: http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1002886


      Delete
    6. DK. Thanks for the reference, but there's no need to be a condescending asshole. You disagree with my claims. I understand that.

      But your reference doesn't say what you seem to think it does. Yes, human populations are geographically structured. Show me where PCA clusters Asians separately from Europeans. If that were so, a PC plot superimposed on a map wouldn't show geographically intermediate populations as genetically intermediate. There would be discrete clusters, which we don't see. Instead, geographic transects give us PC transects.

      You apparently disagree. But where in that paper are the races?

      Delete
    7. What I encountered in my undergraduate was generally the notion that there isn't strong enough isolation to draw sharp lines between human populations.
      Not just that there are intermediates where geographic ranges overlap but that the overall gene flow between areas and even between continents has been a robust phenomenon. I recall far too few details but you can find genetic markers known to have originated in Brazilian populations in even the most isolated human populations (provided that whatever examples I accepted at the time were actually good examples.)

      You've definitely got some measurable morphology trends between the popularly known three groups of the old world, but what is the actual magnitude of these differences? Would an isolated Caucasian in that environment (in historically similar living conditions, however much those matter,) develop the same traits? If so how many generations would we estimate that would take?

      Delete
    8. I thought that would quickly provoke somebody to say most of those subtle differences in facial shapes aren't particularly adaptive but are more the trademark of genetic drift and the other low popularity mechanisms. That the Caucasian population might take on some very shallow traits (I'm talking perceptually here,) that natives developed but generally not shift into looking like the natives.

      I'm not entirely confident in my ability to support that as the actual way these mechanisms would play out, but I expected somebody else here to practically have this on the tip of their tongue will a good deal of support.

      This leaves me a bit worried that I may have picked these notions up from professors who had no more support for it than I. Is there anybody familiar with this subject that can tell me if this is the case?

      Delete
    9. I think you got no reply because nobody is sure what you were proposing. What would be the mechanism for migrants to come to resemble natives? I can think of two: selection and interbreeding (which of course are not mutually exclusive). The second is trivial, and the first would require a selective regime; i.e. what would drive selection here? I could come up with notions, but what's yours?

      Delete
    10. I don't expect many of the recognizable racial features to be anything you could select for. Pigment is the big exception there but as we know fairly large groups of humans move around faster than the selective force can keep up in regards to that trait. Lots of things are under a few constraints of course but racial traits fall in the same boundaries (as far as I can tell) in all regards except cultural preference, but that's really short term compared to how long it took to establish the traits in the first place.

      Delete
    11. Shoku: I would reply to you, but I still have no clear idea of what point you're trying to make, or what question you're trying to ask, if any.

      Delete
  2. Rather than argue that races don't exist, I prefer to note that raceis essentially a social construct: not entirely without utility but scientifically fuzzy. And therefore not really scientific at all.

    ReplyDelete
    Replies
    1. By the way, I think that John Harshman in his first comment gets it right.

      Delete
  3. a distinctive, but somewhat polyphyletic, group that differs from the people living outside of Africa

    Don't you actually mean paraphyletic? If so, then it's people outside Africa that could be regarded as more "distinctive" (and possibly "a little polyphyletic" if several migrations out of Africa contributed to their ancestry, not to mention an odd Neanderthal/Denisovan). Any specifically African features, if not plesiomorphic, can only be due to relatively recent gene flow withing the continent.

    ReplyDelete
  4. I really enjoyed Ian's presentation except for one small comment he made

    Really? He read 100% of it off the printed notes. A big negative, IMO - why not just play record or a video instead? And, as a biologist, how come did you enjoy the talk that spent 6 minutes, or roughly 40% of its total time, to illustrate the falsehood of the belief that "race is described as a skin color"? And you apparently enjoyed a talk that claims that the best definition of a race is one that takes no account of genetics? You did?

    And the last quarter of his talk simply signifies his utter failure as a statistician to grasp a concept of pattern recognition. All I see is a standard race hustler - and not very original at that...

    The best ever, and in my view totally immune to any reasonable dispute, definition of biological race can be found in The American Heritage Dictionary of English language:

    "Race (biology)
    An interbreeding, usually geographically isolated population of organisms differing from other populations of the same species in the frequency of hereditary traits. A race that has been given formal taxonomic recognition is known as a subspecies".

    100% on target! I find it rather interesting that some anonymous worker bee was able to do a better job defining the simple term than giants like Mayr or Dobzhansky.

    ReplyDelete
    Replies
    1. Worker bee, before you start doing the waggle dance know that Dobzhansky said the following: "Race differences are facts of nature which can, given sufficient study, be ascertained objectively: Mendelian populations of any kind, from small tribes to inhabitants of countries and continents, may differ in frequencies of some genetic variants or they may not. If they so differ, they are racially distinct." [from "Mankind Evolving, 1962 Italics in orginal].

      Delete
  5. Larry - thanks for this. Just saw it today. I will dig into a response over the weekend.

    DK - I'm sorry you didn't like the presentation. I read from notes because I have a tendency to say "um" and "ah" a lot when I don't, and that often means I end up being over-time. When the video comes out, you will see that I did not, in fact, read 100% from notes, rather using them to prompt me when I needed to stay on topic.

    As far as "race hustler" goes, you're going to have to define that term for me, because I've seen it used to describe pretty much every behaviour under the sun, with the only common thread being discussing race.

    ReplyDelete
  6. The difference in skin colour is an adaptation to different environments. Maybe I'm missing something here, but isn't that one of the defining characteristics of a race? We apply it to other species without any problem, but seem to have difficulty when it comes to Homo sapiens. I agree that history has caused it to be a 'loaded term', but we have to be honest. And as far as I know, nobody is trying to say that skin colour has any relationship to intelligence or overall ability. Okay, the late J. Philippe Rushton did, but I think he's been thoroughly discredited.

    ReplyDelete
    Replies
    1. Biologists studying all species, not only humans, are realizing these same definitional challenges.

      Delete
  7. For this YEC creationist the race/evolution subject is a problem for evolutionists.
    They have to say intelligence is conditional on stages in evolved beings and therefore in segregated stages between close biological creatures but with human beings they must not do this.
    Its funny to see the discomfort.
    I often say race may be a geerm that seriously discredits evolution suiddenly.

    IN fact YEC creationists use this issue very well as we have simply Adam/Eve and them being made in Gods image, and not natures, therefore we think like GOd and its impossible for any intellectual innate differences between human beings.
    All differences are from other influences.
    It can always be pointed out how evolution has in the past and still hints that segregated human groups, so profoundly different in body, possibly or indeed have evolved different intellectual innate capabilities.
    Darwin said NO to race as a factor in intelligence. he said we were all the same.
    He did say women were innately intellectually inferior due to evolution however.

    It really is all about whether some races are inferior to others in intellect due to race.
    So the people who were seen as racially inferior tend to want or think they need to eliminate the concept of race.
    As if that to believe there is races leads to conclusions of racial inferiority assertions.

    It does seem evolution was the origin for serious beliefs about racial inferiority.
    I suspect few ever actually believed in races being inferior to others. Its a myth that the "white" man thought so.

    Is there races?
    I think all there is IS segregated groups of breeding human beings.
    If the group has adapted with a result of difference in the body then thats all it is.
    The concept of race as put forth by modern evolutionism has segregated human groups having selection on mutation going on for a long time and so race is a real thing.

    I think there is just segregated breeding groups of humans and so there is no such thing as race.
    Even today race never means a biological group but a group with a common identity including exclusive/ or enough breeding to maintain the segregated identity.

    It takes a creationist to figure it out,.

    ReplyDelete
    Replies
    1. "It does seem evolution was the origin for serious beliefs about racial inferiority.
      I suspect few ever actually believed in races being inferior to others. Its a myth that the "white" man thought so."


      This statement violates any serious reading of history. Notions of racial inferiority predate the concept of evolution by millenia.

      Delete
    2. You conveniently forget the Children of Ham.

      Delete
    3. From the Autobiography of Mark Twain (page 212):

      In my schoolboy days I had no aversion to slavery. I was not aware that there was anything wrong about it. No one arraigned it in my hearing; the local papers said nothing against it; the local pulpit taught us that God approved it, that it was a holy thing, and that the doubter need only look in the Bible if he wished to settle his mind – and then the texts were read aloud to us to make the matter sure; if the slaves themselves had an aversion to slavery they were wise and said nothing.

      Delete
    4. I can settle this for you fairly easily:
      Any genetic disposition for intelligence that varies between races is utterly insignificant in comparison to environmental factors. Presumably the founding population of humanity drove those alleles to fixation and we have not had any notable mutations that improve overall intelligence (even cumulatively.)

      This case seems to be made wide and far (as far as I've seen at least,) so I'm a bit surprised that you haven't encountered it and that so many people have squirmed when asked to explain intelligence between races.

      Delete
  8. Well a pickle as always. Dictionary definition pointed out by DK seems reasonable. Personally not a fan of letting cultural and societal problems regulate scientific definitions (notwithstanding whatever legitimate scientific problems exist in classification). The insistance that there are no categorical genetic differences amongst humans sometimes seems to imply that there would be something inherently wrong with certain people were differences to exist. Although it isn't the intent, I know, maybe this is also racism. But I don't actually know anything about human population genetics so I will read with interest further comments.

    ReplyDelete
    Replies
    1. well, I know enough that pretending there are not genetic differences when of course such differences would arise through reproductive isolation is roughly equivalent to pretending there are not phenotypic differences when such differences clearly exist.

      Delete
    2. What you meant to say is not clear to me from what your wrote. You SEEM to be saying that there are "categorical genetic differences amongst humans", and that you think someone is insisting that there are not.

      If that is what you meant to say, it appears to be a strawman argument: no one in this discussion has said that there are no differences among humans.

      However, the fact that there ARE differences among humans is NOT evidence for the existence of human races. Those differences would have to be of a particular nature to be so, and they are not.

      It is the lack of discrete genetic boundaries between human populations that make up the scientific case for the non-existence of human races, not a lack of any genetic differences at all.

      Delete
    3. ok, I should refrain from posting while drinking wine as I was last night...but I was not attempting to erect strawman. Rather, was referring to genetic differences that in fact would be of a particular nature to qualify as evidence for races, not just any differences. But I have read your points and since there seems to be some debate on the overall matter, I will continue to read.

      Delete
    4. "However, the fact that there ARE differences among humans is NOT evidence for the existence of human races. Those differences would have to be of a particular nature to be so, and they are not."

      What particular nature of differences would qualify in your opinion?


      "It is the lack of discrete genetic boundaries between human populations that make up the scientific case for the non-existence of human races, not a lack of any genetic differences at all"

      What discrete genetic boundaries are there between different races of e.g. dogs? Or do you think there are no races in dogs?


      As you correctly state, no one argues that there are no genetics differences between discreet human populations (Asians, Blacks, etc). The whole point is how do we clearly define what constitutes a race or not and as such come to the conclusion that there are human races or not. This is something that quite honestly is not clear to me at all, and it seems that a lot of biologists will have no problem using the term race everywhere but suddenly come to halt when it comes to humans because they are afraid that will help racism. There's a lack of coherence regarding this question. I'm not saying it's an easy question; one just has to look at *ring species* to see that there's not even a clear definition of species even at the animal level that works flawlessly. But we need to be as consistent as possible.

      Delete
    5. Actually, biologists seldom use the term "race" these days. "Subspecies" is the common term. And in fact, some biologists deny that subspecies is a useful concept. Subspecies are most often geographically isolated populations, which doesn't generally happen in humans. There should at least be some sort of discontinuity, which again we don't really see in humans. Instead we see fairly smooth variation and differences among populations that increase with distance. It's easy to tell Thais from French, but not so easy to tell Uighurs from Turkmens. So what exactly is an "Asian"?

      As for dogs, there are no races of dogs; there are breeds, and breeds are maintained by artificial selection, a form of enforced isolation.

      Delete
    6. I'm aware of the term subspecies (I work in biology), but it doesn't help either if we substitute subspecies for race. For the general public it will sound even worse.

      And as I said, I'm not saying that these concepts are set in stone or that they are perfect. I referred to the problem of the concept of species, which is far from solved, but which is still useful. The question here is if the concept of race/subspecies is also useful or not. If it is, then what is the definition and does it apply to humans or not and why.

      As for dogs, maybe you're right (I work in microbiology/genetics), but being the product of artificial selection (through selective breeding and enforced isolation) doesn't mean you can't obtain different subspecies/races. One doesn't imply the other, I think, or does it? If I create a new species in a lab are you going to tell me that it's not a new "species" because I made it? What about dogs, cows, wheat, etc, aren't they all considered different species from their natural original counterparts even though they were obtained by selective breeding? If that is the case, why the problem when it comes to subspecies instead of species?

      Delete
    7. You could call different breeds of dog subspecies if you liked. They do fit the common notion, more or less. But nobody does. There's no perceived utility in talking about subspecies of domestic animals. However, if you did, it would be instructive: dog breeds are easily identified and separable from all other breeds. A dog either is a cocker spaniel or is not. Now try that with "Asian" (by a means other than location).

      As I've said, there's considerable argument in biology about whether "subspecies" is a useful concept. Those who favor the phylogenetic species concept generally prefer to recognize what would otherwise be called subspecies as phylogenetic species. Those who prefer the "biological" species concept talk about polytypic species, and designate subspecies, most commonly for isolated populations. Splitters vs. lumpers, to some degree. But in the 19th century, it seems as if every tiny variation got its own subspecies, and many of those aren't diagnosable at all, other than by location; we're still cleaning up that mess.

      Delete
    8. I agree with you in everything you said regarding the tricky business of the use of the concept of subspecies. I also mentioned before that even the concept of species is far from perfect.

      "dog breeds are easily identified and separable from all other breeds. A dog either is a cocker spaniel or is not. Now try that with "Asian" (by a means other than location)."

      True, but you can identify someone as "asian" versus "african" or "white" or whatever is the fashion these days. The question here is if it makes sense to call that race/subspecies or just consider it variation within a population. I'm agnostic on that, the only thing I want is consistency of use, and sometimes that consistency appears lacking.

      Delete
    9. I defy you to identify a randomly chosen person from the world as Asian or African or White. OK, a high proportion of those will be Chinese, which you will probably call Asian. But what are you going to do with Iranians? Pushtun? Gurkhas? How about a randomly chosen Brazilian? What's a Melanesian? A Keralan? I could go on.

      Consistency is lacking because so much of the assignment is arbitrary. Life is fairly easy if you're only trying to separate Scots from Nigerians from Chinese. Or, as another poster said, South American Indians from Central Asians from Malagasy. But if you have to deal with all the continuous variation of the real world, races just don't work.

      Delete
    10. Harsham, I already said I agree with you. I'm not defending that we should consider them races. What I'm saying is that the concept of races/subspecies is too arbitrary. Surely I can separate broad categories, but they will be far from perfect, and when you get down to very specific ethnologies it gets far worse. My point is only that we should try to be consistent across the board, nothing else. And as I said before, even at the level of species it gets trickier. I think we all agree that there is divergence among broad human groups. The question is if it makes sense or not to call them races and where do we draw the line if we do so.

      Delete
    11. I'm not quite sure what you mean by "divergence among broad human groups", so I'm not sure if we all agree. What I would say is that there's divergence between any two geographically distant populations.

      Delete
  9. First, let me say I'm not a human geneticist, I'm a botanist. That said....

    Genetically isolated does NOT mean there's no gene flow between the groups. Is there was none, they would be different species.

    I disagree. While arguing species concepts is a losing battle, this is a fairly loose interpretation of any species concept with which I am familiar.

    Secondly, race is a taxonomic rank. To be valid, any taxonomic rank demands description, publication and vouchers. And unless one is looking to pad their CV, establishing taxonomic ranks should serve some scientifically useful purpose. In any event, I am aware of no such publications and no vouchers against which we can compare human and assign them to races. Even if such a publication exists, the taxonomist had to make subjective decisions about which suite of characters define the race and how much difference warranted delineation into separate races. Defining below the taxonomic rank of species is just as specious as defining ranks above it.

    Yes, there is genetic structure within species that we can use to build phylogenies. And yes, we can decorate our trees with ancillary data to tell, for instance, a nice biogeographical story about our ancestors. But we need to communicate that phylogenies are hypotheses, and as such, need to be narrowly interpreted. It seems entirely acceptable to say "individuals with Character A can trace part of their lineage back to region X". It does not seem okay to say "individuals with Character A are RACE NAME." The latter is to use the phylogeny as a blunt force instrument. I think helping people understand the limits of phylogenies is vitally important lest the layperson use race (as they have done already) to label and subjugate others based on a minute fraction of their genome.

    ReplyDelete
    Replies
    1. It seems entirely acceptable to say "individuals with Character A can trace part of their lineage back to region X". It does not seem okay to say "individuals with Character A are RACE NAME."

      I don't understand why this bothers you so much. Is it because we're dealing with humans? If we were discussing the subspecies of a particular plant, say dandelions, would you still have the same objections?

      Or is it the fact that you name one particular character? Do you agree that we can look at the DNA of an individual and determine with high probability whether their closest relatives live in Africa, Asia, or Europe? We have to use several characters to reach that high probability but one or two will still be good enough in most cases.

      If you did this with dandelions you wouldn't hesitate to call them subspecies or races, would you?

      I think helping people understand the limits of phylogenies is vitally important lest the layperson use race (as they have done already) to label and subjugate others based on a minute fraction of their genome.

      I think it's always wrong to distort or misrepresent science on the grounds that the truth might be abused. The fact that human races exist does not mean that discrimination (racism) is justified.

      Delete
    2. Do you agree that we can look at the DNA of an individual and determine with high probability whether their closest relatives live in Africa, Asia, or Europe?

      Some individuals. Others, not so much. You can easily distinguish individuals from widely separated locations (or could before the modern mass migrations began), but not so easily from closer locations. So where does Asia end and Europe begin? A transect across the Silk Road would cause problems for your ideas. A transect from India to China across the Himalayas would cause similar problems. Not to leave Africa out, and transect up the Nile, ditto. There's plenty of geographic variation in H. sapiens, but any biologist who tried to divide it into subspecies would end up with nothing useful. Clinal variation just doesn't work well for this.

      Delete
    3. The same way you could pick any 3 points on earth far enough and cluster people into them. Why don't we cluster humans whether they are South American Aboriginal/Central Asian/Malagasy. I could sequence your genome or anyone's and say they fall into one of these clusters with high confidence a lot of the time - therefore humankind is broken down into 3 races - South American Aboriginals, Central Asians, and the Malagasy people.

      You realize that all you're doing is creating artificial groups from a gradient of variation.

      Delete
  10. How about a thought exercise!
    I am YEC but will use your terms.
    Say there is a breeding population , separated by a mountain chain from another and then another mt chain with another population.
    They breed for 10,000 years completely segregated.
    At the end the first and third populations look almost or totally alike but the middle looks dramatically unlike the other two because of unique environment..

    Are all three RACES or just two races?
    If simply being segregated breeding populations makes one a race then there are races.
    Yet if only looking differently is what allows races then there are no races.

    All there is IS segregated breeding populations and its a coicedence if they look different.
    Its been clumbsy thinking by evolutionism to simply define race by looks.
    Further it ignores totally unlike "races" could look alike for like adaptations to the environment.


    ReplyDelete
  11. Human populations that have been isolated from each other for many generations aren't Africans, Europeans and Asians so far as I know. Australian Aborigines and Amerian Indians and African pygmies (sorry if there's a politer word now in use, I don't know it.) New Guinea Highlanders and Pacific Islanders and Inuit I think also seem to count. In any event, the sets of alleles that distinguish such groups don't seem to overlap with anything that has been previously meant by the term "race." And I'm sorry, I don't think it really is so easy to distinguish Tamils, Solomon Islanders, Yoruba or Malays, Nepalis, Yaquis, Chukchis. About all I really get is that most people feel quite confident in identifying European, aka "white." I don't think it's so unreasonable for people not to want to go there.

    ReplyDelete
  12. Ian Cromwell has a response up, here: http://freethoughtblogs.com/crommunist/2012/12/10/a-response-to-larry-moran/

    I (and probably others) would love to hear your thoughts on it.

    ReplyDelete
  13. I probably should have said this a while ago, but "...a distinctive, but somewhat polyphyletic, group..."? Did you even read that to yourself before posting? Polyphyletic groups aren't real groups. You should have been called on that a while ago. I apologize for the delay.

    ReplyDelete
    Replies
    1. John,

      Unfortunately, biology isn't as simple as you imagine.

      Think of any cladogenesis event where a small part of the parent population become geographically isolated and eventually evolves to the point where the individuals can no longer interbreed with the members of the larger parental population.

      At that point we have two species where there used to be only one. When you construct a phylogenetic tree using DNA from shortly after the speciation event, you will discover that the "parent" species is paraphyletic. That's the word I should have used as some helpful commenter pointed out.

      Do you agree that we commonly refer to some distinct groups that are paraphyletic, as in the parent species in my example?

      Delete
  14. Larry,

    Paraphyly and polyphyly are quite different animals. Yes, we allow for paraphyly in species; we have to if we're using the "biological" species concept. (Of course, given enough time, that paraphyly goes away and both groups become monophyletic.) But in such cases the "daughter" species has some identifiable synapomorphies and the "parent" species some identifiable symplesomorphies that make both groups diagnosable. What do you have? And why is Africa one race instead of lots of them? It's all arbitrary. For species there's an objective criterion (or several, depending on that species concept). For subspecies, there is too. For human subspecies, not so much.

    ReplyDelete
    Replies
    1. "For subspecies, there is too."

      Whats the criteria for subspecies?

      Delete