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Thread: Interesting opinion piece on evolution

  1. #121
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    When scientists complain that creationists and IDers "do not understand the definition of 'theory'", they are also co-opting a word. Sometimes, semantics is important.
    While I won't blame anyone for referring to social change as 'evolution' in generic contexts, and may in fact do so myself on occasion, I think that using that term in a conversation that started out being about biological evolution is potentially misleading, and should be avoided.

  2. #122
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    I will agree with that, the distinctions are too fundamental to lump social evolution together with biological evolution. The same can be said about the "meme" vs. "gene" analogy, it has merits, but runs the risk of glossing over too many differences. Best is to clearly lay out both the similarities and the differences, the old "compare and contrast" game.

  3. #123
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    I agree that the two types of evolution are fundamentally different, but it looked to me as if you only allowed the use of the word evolution to describe something similar to Darwinian evolution, while even in biology, that isn't the only kind of evolution (although the only basically correct kind, but that is something different).
    I think we all understand each other but just put different emphases (emphasises?).

  4. #124
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    Quote Originally Posted by archman
    No, I am not. But we don't work with humans, which is perhaps where the confusion lies. I work with animals.

    Phenotypes are the classic and still all around most popular method for differentiating sub-populations within wild species. Where genetic study comes in, it is very common for us to verify (and occasionally refute) genetic distinctiveness within sub-populations.
    Those biologists would be wrong if they equated a phenotype with genetic human races.

    Phenotype
    From Wikipedia,


    The phenotype of an individual organism is either its total physical appearance and constitution, or a specific manifestation of a trait, such as size or eye color, that varies between individuals. Phenotype is determined to some extent by genotype, or by the identity of the alleles that an individual carries at one or more positions on the chromosomes. Many phenotypes are determined by multiple genes and influenced by environmental factors. Thus, the identity of one or a few known alleles does not always enable prediction of the phenotype.

    Nevertheless, because phenotypes are much easier to observe than genotypes (it doesn't take chemistry or sequencing to determine a person's eye color), classical genetics uses phenotypes to deduce the functions of genes. Breeding experiments can then check these inferences. In this way, early geneticists were able to trace inheritance patterns without any knowledge whatsoever of molecular biology.....
    We aren't using wildly different definitions. You just have not seen, read or been introduced to the results of the research in human genetic variation. Biologists were not aware 20 years ago how closely we ALL turned out to be related. They also were only aware of Mendelian inheiritance. They weren't as keenly aware of the details such as a single nuclotide substitution can have a profound result. One does not define a new race with every new family lineage of a new DNA mutation.

    Blond is a phenotype. So is type A blood. Are those different races of humans? Think of the 'phenotypes' you have in mind which you believe represent race. What would make them equal a 'race' that differs from any other trait you can group people by? Phenotype alone clearly is not the equivalent of race.

    There are many inheritable genetic traits or characteristics. None of them, whether skin color or lip shape or whatever, constitutes a racial group. We are all a combination of those genetic factors in pretty consistent mixes.

    Where genetic work becomes VERY useful is where we find genetic distinctiveness in phenotypically identical organisms, separated by not-so-great geographical distances. I'll throw out the brachyuran crabs Menippe adina and Menippe mercenaria as a recent example of this, as I work in an invertebrate lab. Another case of genetically distinct stocks I know off offhand includes the "offshore" and "inshore" west Atlantic bottlenose dolphins (Tursiops truncatus). I only have secondhand word regarding orcas, but they are considered to have genetically distinct sub-populations as well, as are other cetacean species.
    My guess would be, the faster an organism mutiplies, the less time it takes for isolation to lead to more and more distinct subgroups. And, in the case of domestic animals, humans sped up the process with selective breeding. Humans may very well have developed true genetic races given more time in isolation. It just didn't happen in the time we were separated in early migration. It took thousands of years for humans to develop lighter skin as they migrated north, for example. It only takes a few months to develop a strain of mice in the lab resistant to Leptin. And after a bit of human direction one gets all the mice in the group to have the resistance. That's a very big difference.

    quote? did you mean to cite this or is it your statement? Genetics-inferred, within-species distinctness is very much acknowledged in the animal world, and subject to very high levels of current research. It is the focus of entire theses. Which is why I find it difficult to understand that such distinctness is not claimed to occur in humans. We have clear and present differences in physical appearance that can be unequivocally traced to ethnicity. Pedantics aside as to what is/isn't the true definition of "race", there SHOULD BE genetic markers differentiating ethnic groups.
    It may seem counterintuitive since we have become accustomed to 'seeing' the differences. But once the genetic insides were revealed, it turned out we were seeing something that wasn't there.

    I don't get it. Either the animal and human biologists use different genetic tests, or they're using wildly different definitions of genetic distinctness. If I can take two visually identical (down to mouthparts!) stone crabs from opposite coasts of Florida and determine that they genetically represent different stocks from the same species, how is it that we cannot infer the same between Australian aborigines and Vikings?
    Well, if you want to infer that every blond is one race, and every one with type A blood is another, then you can try to group humans into races. But where do you put the two blonds with two different blood types?

    If you take the genome of both a Viking and an Aboriginal you will find they are indistinguishable except for that 0.1%. The trouble is, if you take just Aboriginals or just Vikings, you'll find they also differ by the same amount. And, you won't find a consistent subset in that 0.1% among either group that you can point to and say here's a consistent difference.

    You are having a hard time letting go of the fact that you think you see a race difference between two groups. After all, there are pretty large visual cues to the difference we have come to identify as race. And, it is complicated by the fact that a certain appearance is seen more commonly among a geographical region. But, why don't we define different blood types as different racial groups? Because race is an arbitrary cultural/ethnic division, not a true genetic division.

    What you need to stop and think about is, what does that physical difference represent genetically? In the human race, our outward appearance is made up of a very small percentage of our total genetic material. In addition, the very tiny bit of genetic variation we have between each other has a lot more activity than mere skin color and body/facial features. If you have an Aboriginal and a Viking that both have type O blood and one of each with type A blood, which is more the important phenotype to define the race of each of the four? Suppose outward appearance consisted of less genetic material than differences you have to test for? If you chose appearance because you knew the geographic location played a role, then you'd be choosing geography over biology. That's ethnic, not biologic.

    Consider also, while some genetic variations might be more common in any one group, sickle cell trait for example, not everyone in such a group has that genetic variation.

    There is no single variation or group of variations common to all Aboriginals or other groups who appear to be of different races. Any mutations that occurred after the initial group(s) migrated out of Africa would not exist in population groups left behind and any mutations that occurred in the groups left behind after the migration would not exist in the group that left (unless the mutations occurred additionally in each group). However, the migration groups contained enough members and mutations occurred sufficiently slowly, that all the humans who have migrated around this planet have not diverged from one another. What you see as divergence is arbitrary.

    Quote Originally Posted by archman
    Quote Originally Posted by beskep
    There are no genetic differences that all members of any ethnic group have. Even if the group members all look alike, not all of them will have the same combinations of genes to give them that appearance.
    I would assume that with modern humans at least, between-population interbreeding will bias a lot of contemporary measurements. But accounting for that, there should be genetic patterns that explain why it is that Asians look fundamentally different in appearance from west Europeans. After all, the pattern IS there. It's certainly not environmentally-derived.

    What's the cutoff? If they become incapable of breeding, that classically rates as a separate species. If they don't, they get lumped into a subsidiary taxonomic ranking.
    The cutoff is when you can find the genetic variation among two humans that is greater than the variation among any other two humans. Allow me to review the evidence from memory, you can find the research on the net under Mary Claire-King, Maynard Olsen et al. Their research involved sampling thousands and thousands of members of various populations including sampling members of the most isolated groups. The result was a very detailed map of human migration following various genetic 'markers'. 'Markers' are single mutations that occurred after the group migrated out of a particular region or a mutation in the group left behind. Markers on the Y chromosome were used so as to follow direct male lineages. Mitochondrial DNA markers were used to follow direct maternal lineages. The researchers I'm citing put many studies together in their work.

    What the U of WA researchers found was that most of human genetic variation, (about 85% of the variation or 0.85x0.1% of all of our variable DNA), can be found within any group, even the smallest isolated populations. The results of the research revealed that, (except for identical siblings and as I said I haven't checked how first degree relatives fit in), any 2 humans on the planet are as related as any other 2 humans whether or not they are from the same village, the same country, or the same continent. The mutations that occurred after groups separated constitute a mere 0.015% of our DNA and those genetic differences do not belong to any single ethnic race.

    In other words, genetic differences occur within human groups and among human groups in the same amount, and 85% of those genetic differences are evenly distributed around the world. But before you latch on to the 0.015% as your answer (because it isn't), read on.

    If you were going to have racial groups that were more than cultural/ethnic in nature you are relying on the physical appearance which might distinguish a racial group. Most of that appearance would use DNA we all have in common. That would be the 85% of the 0.1% that we differ by that you can find evenly distributed in all ethnic groups. That leaves 0.015% variation that isn't found in every group. These would be the genetic 'markers' where you get true differences between individuals and groups that are not evenly distributed around the planet.

    Those genetic markers are the closest thing to what you are looking for to see a 'race' of humans that has split off from another 'race' of humans. Except, you'd be wrong.

    Those markers migrated all over the planet going this way and that. You have a very small amount left of that 0.015% in any of the 'end' routes of the migrations out of Africa or in the groups left behind. Then consider, only a very tiny amount of that fraction of the 0.015% of our DNA which make up the genetic markers or "differences after groups split" accounts for differences in outward appearance.

    What you have left is probably not enough to even equal a blood type. You have sickle cell here and St Vida's Dance there. You have lots of things you'll find more common in certain family lines. But you won't have anything you can call a genetic 'race', even in the most isolated Aboriginal tribes.

    Heck, dogs all are genetically one species, but they certainly have different genetic variants that are maintained by careful breeding. One strain even comes with a specific defect in the urinary tract that makes them pee out the wrong stuff (dalmatians?). Different dog breeds are routinely referred to as "strains"; I am sure they are even referred to as "races" on occasion. These aren't cultural monikers, certainly.
    The difference is time and isolation. That's how one group diverges from another. If we controlled human breeding I'd bet we could develop different races in a few thousand years. If we were just trying to make people different we could probably do it quicker, but it would take a lot longer than it takes to breed animals that reproduce as fast as dogs. A one year old dog can have pups. Big difference.
    Last edited by beskeptical; 2006-Jan-03 at 09:46 PM.

  5. #125
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    Quote Originally Posted by Wolverine
    Two nitpicks:

    1. Evolution specifically describes a change in allele frequencies over time. It's a biological term which shouldn't be used loosely to describe cultural/societal behavior nor other tangental topics which belong in the sociological arena.
    2. Scientific theories are never "proven" -- proofs are for mathematics, science deals with evidence.
    RE1: Scientifically, technically, perhaps not. I certainly don't have a beef with how someone wants to define the term, evolution. All we need to do is clarify the terminology we're using in a particular discussion. Once we clarified the problem was over the terminology, hey, were good!

    Re2: There is a continuum from "without a doubt" "to no evidence one way or the other". Either one is arguing terminology which I think we mostly all agree on the technical terms, or one is claiming there is not yet overwhelming evidence supporting the theory of evolution. If Fr wayne believes the latter, he is mistaken.

    So, W, I ask you as well, what term do you use to describe non-biological evolution? My dictionary certainly doesn't limit it to any technical biology only usage.

  6. #126
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    Quote Originally Posted by Fr. Wayne
    ....how is it that we cannot infer the same between Australian aborigines and Vikings?" Excellent inquiry here.
    See my excellent answer.

  7. #127
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    Quote Originally Posted by HenrikOlsen
    I saw mention of a study that did just that, using blood samples from lots of englishmen.
    It was shown that the distribution of genetic markers identifiable as being from the vikings fit the geographical areas settledby vikings who then bred with the locals.
    I unfortunately don't have a link, I think it was a BBC World science report.
    Do not mix tracing one's family line or human migration with human groups diverging as two races. You'd be mistaken.

  8. #128
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    Here's a starting place for the race issue and genetics beyond my post.
    The very notion of "race" as a meaningful concept has crumbled under the weight of the Human Genome Project and other data revealing only slight genetic variation among peoples of different continents. Instead, most of the variation occurs among individuals within population groups.
    But don't stop there, go read some of the earlier work that got Ms Claire-King to this point.
    Last edited by beskeptical; 2006-Jan-04 at 10:23 PM.

  9. #129
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    Here's another nice link.

  10. #130
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    Quote Originally Posted by Disinfo Agent
    Here's another nice link.
    Excellent link.

  11. #131
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    Quote Originally Posted by beskeptical
    So, W, I ask you as well, what term do you use to describe non-biological evolution? My dictionary certainly doesn't limit it to any technical biology only usage.
    My apologies, I'm an incorrigible pedant that happens to be peeved by usage of the term outside of biological discussions. I have a similar aversion to using the term "theory" to mean anything but the scientific variety.

    In answer to your question, it would specifically depend on the subject matter. Don't let my grumpy verbiage dissuade you -- I just thought it prudent on a thread devoted to biological evolution to refrain from bandying about alternate usages with separate connotations.

  12. #132
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    Man, humans stink!

    Alright, I've done my own research and talked with a few of my colleagues, and figured out what the deal is with humans. I skimmed over your oustanding 3:19pm posting bestskeptic, which corroborates some of my earlier confusion. Actually your remarks threw off not only I, but 2 biology graduate students, 1 botany graduate student, and one full professor of zoology. I guess we should all brush up on our human knowledge…

    I'll bulletize for simplicity.

    1. Humans are genetically strange. For some reason (perhaps bottlenecking combined with species age), populations do not exhibit *normal* genetic variation that is to be expected in a mammal line with such a large population size and geographic dispersal. That’s basic population genetics theory.

    2. Modern humans are arguably not a discrete species, but a subspecies, specifically Homo sapien sapiens. Which would possibly reduce lineage age to the lower Pleistocene. That helps.

    3. Geographic separation is not very good with humans, even historically.

    The pattern of overall genetic differences instead tells us that genetic lineages rapidly spread out to all of humanity, indicating that human populations have always had a degree of genetic contact with one another, and thus historically don't show any distinct evolutionary lineages within humanity,"
    http://www.sciencedaily.com/releases...1008051724.htm

    4. This doesn’t help.
    "Humans expanded again and again out of Africa," Templeton concluded, "but these expansions resulted in interbreeding, not replacement, and thereby strengthened the genetic ties between human populations throughout the world."
    5. Ecologists and zoologists use the “race” classification ambiguously. We do not use it in the strict historical context adopted by many human biologists. It does not have to be used by biologists in the same way that Alan Templeton used it in his landmark paper. To us, “race” is often synonymous with “strain”, “breed”, and “sub-population”. That annoying wikipedia has a decent synopsis of biological “race” identifiers.
    http://en.wikipedia.org/wiki/Race#Su...itions_of_race

    Actually, this is the best thing I’ve ever seen on wikipedia. It very well explains how “race” in humans is still far from being settled in Biology. This is a good read... I wonder who the contributors were?

    6. In making taxonomic distinctions, a higher percentage of within-population genetic variance does not necessarily negate smaller percentages of between-population variances. If the between-population variances, however small, influence morphology, appearance, and yes even behaviour, they can qualify as separate genetic lineages. Which can and is often referred to as “race”. But nowadays we prefer using functionally significant descriptors. “Ecotype”. “Sub-Population”. “Meta-Population”. “Morphotype”. There are lots of others. As an ecologist, I am even permitted to make up my own!

    I have a starfish species sitting in my research lab that I could, if I choose to, split up into subspecies, OR additional species, OR strains. Heck I could even call them races! I doubt THAT would get past the peer-review committee, however. Ha Ha.

  13. #133
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    Cool

    Quote Originally Posted by archman
    3. Geographic separation is not very good with humans, even historically.

    http://www.sciencedaily.com/releases...1008051724.htm
    Also from that article:

    The trellis model pictures humanity as a latticework, each part having a connection with all other parts. It recognizes that modern humans started in Africa about 100 million years ago, but as humans spread, they also could, and did, come back into Africa, and genes were interchanged globally, not so much by individual Don Juans as through interchanges by adjacent populations.
    To me, this is one of the most compelling finds of genetics: racial purity is a myth. There has never been any such thing in our species.

  14. #134
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    Quote Originally Posted by Disinfo Agent
    Quote Originally Posted by Archman
    3. Geographic separation is not very good with humans, even historically.

    http://www.sciencedaily.com/releases...1008051724.htm
    Also from that article:

    The trellis model pictures humanity as a latticework, each part having a connection with all other parts. It recognizes that modern humans started in Africa about 100 million years ago, but as humans spread, they also could, and did, come back into Africa, and genes were interchanged globally, not so much by individual Don Juans as through interchanges by adjacent populations.
    To me, this is one of the most compelling finds of genetics: racial purity is a myth. There has never been any such thing in our species.
    Nitpick: A 100 million years ago? I suppose they mean either 10 million (for very early hominids) or 100 thousand (for homo sapiens sapiens)...
    I agree with your conclusion though!

  15. #135
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    Quote Originally Posted by archman
    Man, humans stink!

    Alright, I've done my own research and talked with a few of my colleagues, and figured out what the deal is with humans. I skimmed over your oustanding 3:19pm posting bestskeptic, which corroborates some of my earlier confusion. Actually your remarks threw off not only I, but 2 biology graduate students, 1 botany graduate student, and one full professor of zoology. I guess we should all brush up on our human knowledge…
    [beaming]Thanks, I did spend a bit of time trying to make my points clear.

    I'll bulletize for simplicity.

    1. Humans are genetically strange. For some reason (perhaps bottlenecking combined with species age),
    Interesting side point: there was a severe bottleneck before we left Africa where humans may have dwindled down to as few as a thousand or so members.
    ....this is the best thing I’ve ever seen on wikipedia. It very well explains how “race” in humans is still far from being settled in Biology. This is a good read... I wonder who the contributors were?
    Well it is settled among geneticists.

    But you do have a point here. I am one of those people who know a "little about a lot". In being so curious I have discovered how isolated many scientific fields are from one another. It also happens to be true in some occupational fields.

    In science, biology astronomy and geology are finally beginning to interact in a more serious way. They merged the overlapping areas of those departments into one here at the U of WA. Genetics is beginning to merge with biology fields. Genetics has, interestingly, merged with computer technology. That new field is called 'Bioinformatics' or something like that. It takes computer data managing programs to deal with the amount of information in genetics.

    6. In making taxonomic distinctions, a higher percentage of within-population genetic variance does not necessarily negate smaller percentages of between-population variances. If the between-population variances, however small, influence morphology, appearance, and yes even behaviour, they can qualify as separate genetic lineages. Which can and is often referred to as “race”. But nowadays we prefer using functionally significant descriptors. “Ecotype”. “Sub-Population”. “Meta-Population”. “Morphotype”. There are lots of others. As an ecologist, I am even permitted to make up my own!

    I have a starfish species sitting in my research lab that I could, if I choose to, split up into subspecies, OR additional species, OR strains. Heck I could even call them races! I doubt THAT would get past the peer-review committee, however. Ha Ha.
    You may still just be having a hard time integrating this new idea of no genetic 'races' in humans into your view of things. You're still leaving out that the idea skin/hair/eye color and body/facial features are not significant features when categorizing human genetic divisions. They are arbitrary divisions. I could just as easily choose blood type except you can't see it without a lab test. You may think you are seeing homogeneous traits merely because they are dominant traits. There could be just as much genetic mixing in that Aboriginal group as elsewhere but with their outward features being dominant traits you don't see the mixing.

    There is evidence that Mediterranean sailors traveled to Ethiopia and remained. They intermarried and all the offspring have Negro features with the immigrant features having been sort of washed out. But they are nonetheless a mixed population. Given the 40 to 65,000 years of human migration there has been opportunity for remixing the genes many times.

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    It's interesting that people trying to disprove the idea that the human species has races actually end up arguing a few different points that aren't quite the same thing as that:

    1. They argue that the "races" have not been in complete genetic/reproductive isolation.
    2. They argue that the "races" contain greater genetic variation within themselves than there is between them.
    3. They argue that the physical traits we use to identify "races" are based on an insignificant amount of the total genome.

    But these things only disprove the existence of races if we first postulate these equivalencies:

    1. The definition of "race" requires complete genetic/reproductive isolation.
    2. The definition of "race" requires greater genetic variation between races than within them.
    3. The definition of "race" requires that the traits separating the races must constitute some arbitrarily-defined significant amount of the total genome.

    In other words, to combine 1 2, and 3, a genetic argument against race requires the belief that race is even supposed to be a genetic concept in the first place. But that's not what it's about and never has been; the concept of races even vastly predates the concept of genetics. So such genetic arguments don't really invalidate the concept; they just try to shift over to another one that's more invalidatable. That's a form of the straw-man tactic, by attempted word-redefinition. And trying to sneak such premises past us without stating them is trying to rope us into accepting them as facts ourselves without question even though they might not be accepted if they were really considered on their own merits.

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    Quote Originally Posted by Delvo View Post
    It's interesting that people trying to disprove the idea that the human species has races actually end up arguing a few different points that aren't quite the same thing as that:

    1. They argue that the "races" have not been in complete genetic/reproductive isolation.
    [...]

    1. The definition of "race" requires complete genetic/reproductive isolation.
    Complete isolation is not a necessary requirement. But they have to be very isolated, according to the common definition of 'race' ('subspecies') in biology.

    Human populations have never been that isolated, as genetics keeps showing again and again.

    Quote Originally Posted by Delvo View Post
    2. They argue that the "races" contain greater genetic variation within themselves than there is between them.
    3. They argue that the physical traits we use to identify "races" are based on an insignificant amount of the total genome.

    But these things only disprove the existence of races if we first postulate these equivalencies:

    [...]
    2. The definition of "race" requires greater genetic variation between races than within them.
    3. The definition of "race" requires that the traits separating the races must constitute some arbitrarily-defined significant amount of the total genome.

    In other words, to combine 1 2, and 3, a genetic argument against race requires the belief that race is even supposed to be a genetic concept in the first place.
    And that's precisely how most people have conceived of 'race' in the last few centuries -- both popularly and in scientific contexts.

    It's not a straw man; you have just not thought through what 'race' as we commonly understand it is supposed to mean, or how the word has been used by most in the last 200 years, at least.

    If you 'strip' race of its discrete, heritable, biological component, you are left with something unrecogniseable to most people as 'race', even today. You're left with a social notion more akin to 'tribe' or 'culture' (which, in actual fact, is all the races we know and love truly are).
    Last edited by Disinfo Agent; 2006-Dec-31 at 08:54 PM. Reason: replaced words w/ synonyms

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    Quote Originally Posted by Disinfo Agent View Post
    Complete isolation is not a necessary requirement. But they have to be very isolated, according to the common definition of 'race' ('subspecies') in biology.
    What definition is that? I can't think of another species for which the next lower level of grouping down ("breeds" for animals, "varieties" for plants) has such a requirement. In fact, I see exactly the opposite pattern in each species I know of. Flowers are different varieties if one's petals have wavy edges or different-colored specks or whatever and the other's petals have straight or single-curved edges or monochrome color, even though the plants are identical in every other way. The kind of honeylocust tree planted in cities and towns is a different variety from most honeylocust trees found in nature, based on exactly one trait and nothing else (the lack of those scary evil thorns that are so gigantic they could be used as weapons and branch out to multiple points/tips so they resemble deer antlers). Ranchers & farmers distinguish cattle breeds by things like the curvature/straightness of the horns or the slope of the spine at the shoulder and a few other traits like that regardless of the rest of the traits that make all cattle cattle or how much of the bovine genome it takes to create those differences. Horse breeders will point out two breeds of horse that look the same to me based on size and shape, because they say one of them has a narrower or longer face or something, to such a minor extent that I can't see the difference at all. Even breeds of dog, often used as an example of the wide variation that a single species can encompass, have mostly only been "distinct" for a few centuries and vary only in a handful of parameters like size and color, no more than the list of parameters human races vary in. One species of mushroom found in Europe and North America is divided into two varieties because the ones from one continent can have mind-altering effects on humans and the ones from the other continent don't, which not only is one single solitary trait but is even one we haven't figured out the source of yet, so there's no physical, genetic, or strictly/formally chemical way we can tell them apart at all!

    When and where has division of any given species into groups at a lower level than "species" EVER been based on genetics or anything but a handful of traits that could be called arbitrary in their significance? Maybe you can give some examples of it, but it certainly has never been a requirement for separating breeds/varieties/races, as the numerous examples to the contrary show. All that's required in general is that there are some physical traits that seem to be either easy to spot and/or noteworthy to somebody for any reason, and which are inheritable. Anything bigger than that is just extra.

    You could say that the differences that such divisions are based on are insignificant, but that's a very different thing from saying they just don't exist.

  19. #139
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    You guys do realize that this thread is a year old, right?

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    Quote Originally Posted by cjl View Post
    You guys do realize that this thread is a year old, right?
    once a good thread, always a good thread

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    True, but it appears the original article is no longer there

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    Quote Originally Posted by Delvo View Post
    What definition is that? I can't think of another species for which the next lower level of grouping down ("breeds" for animals, "varieties" for plants) has such a requirement. In fact, I see exactly the opposite pattern in each species I know of. Flowers are different varieties if one's petals have wavy edges or different-colored specks or whatever and the other's petals have straight or single-curved edges or monochrome color, even though the plants are identical in every other way. The kind of honeylocust tree planted in cities and towns is a different variety from most honeylocust trees found in nature, based on exactly one trait and nothing else (the lack of those scary evil thorns that are so gigantic they could be used as weapons and branch out to multiple points/tips so they resemble deer antlers). Ranchers & farmers distinguish cattle breeds by things like the curvature/straightness of the horns or the slope of the spine at the shoulder and a few other traits like that regardless of the rest of the traits that make all cattle cattle or how much of the bovine genome it takes to create those differences. Horse breeders will point out two breeds of horse that look the same to me based on size and shape, because they say one of them has a narrower or longer face or something, to such a minor extent that I can't see the difference at all. Even breeds of dog, often used as an example of the wide variation that a single species can encompass, have mostly only been "distinct" for a few centuries and vary only in a handful of parameters like size and color, no more than the list of parameters human races vary in. One species of mushroom found in Europe and North America is divided into two varieties because the ones from one continent can have mind-altering effects on humans and the ones from the other continent don't, which not only is one single solitary trait but is even one we haven't figured out the source of yet, so there's no physical, genetic, or strictly/formally chemical way we can tell them apart at all!

    When and where has division of any given species into groups at a lower level than "species" EVER been based on genetics or anything but a handful of traits that could be called arbitrary in their significance?
    I suspect biologists may use a stricter definition of "subspecies" (the term "race" is shunned, nowadays) than cattle breeders, for instance, but I am neither one nor the other.

    Anyway, accepting all you have written, then one must also accept that "races" are arbitrary groupings of individuals based on a handfull of arbitrarily chosen criteria. This is what people mean when they say that race does not exist. In that sense, if you tell me that a given plant belongs to the "straight petal race" and another belongs to the "curly petal race", then that is something real about them, but all you are saying is what shape their petals have, nothing more.

    The trouble is that during the last couple of centuries many people tended to assume that a person's race said something more profound about them, than just the physical traits which were being used to define that race. Moreover, when humans are involved, "race" is not necessarily perceived according to physical/biological traits only. Social expectations and preconceptions typically play a role in racial classification, as well.

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