# Can Humans and Chimps Breed? **URL:** \ **Category:** Factual Questions\ **Created:** [March 23, 2001, 4:01pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163 "2001-03-23T16:01:08Z")\ **Posts on this page:** 19\ **Page:** 3
**Author:** ![Allworthy](https://avatars.discourse-cdn.com/v4/letter/a/7cd45c/32.png) [@Allworthy](https://boards.straightdope.com/u/Allworthy)\ **Post date:** [March 25, 2001, 3:38am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/41 "2001-03-25T03:38:21Z")
March 31, 2001 (AP) - Scientists at the Woodley Labs in Tacoma Park, MD, have announced the termination of the controversial National Chimpanzee-Human Hybridization Program, citing the prohibitive cost of the massive quantities of banana daquiris necessary to the success of the project. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [March 25, 2001, 3:40am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/42 "2001-03-25T03:40:48Z")
> [@](#): > > \*Originally posted by Jois \* > \*\*The human sperm doesn’t just enter the human ova, yes, they lied to all of us in school! There has to be a “hundred” more things that happen. Things that range from our pH, enzymes in the ova that destroy odd bits of chromosome from the sperm, fussy details about motility - when I start looking at this in detail I wonder that we ever make babies at all. Some recent paper has found fetal changes depending on where the sperm entered the ova? I can’t remember which species this was. There isn’t much that is neat and straight forward about this process either. > \*\* This raises an interesting idea regarding speciation. Perhaps humans and chimps are technically compatable as far as their chromosomes or development genes go; but suppose the human/chimp lineage split due to a single mutation in the enzymes that allow a sperm to fertilize an egg. For that matter, maybe some cases of human infertility are caused by such a mutation. It could be that humans and chimps aren’t naturally interfertile, but it could be accomplished with a minimum level of biochemical intervention. ---
**Author:** ![Jois](https://avatars.discourse-cdn.com/v4/letter/j/ea666f/32.png) [@Jois](https://boards.straightdope.com/u/Jois)\ **Post date:** [March 25, 2001, 5:26am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/43 "2001-03-25T05:26:00Z")
Hi Lumpy, I agree it wouldn’t take much to make the system not work and maybe that the reverse might not be that difficult either. Just seems the former is always more difficult than the latter! Allworthy, I thought those newspaper just showed up one day in advance. 🙂 Jois ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [March 25, 2001, 6:55pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/44 "2001-03-25T18:55:53Z")
To directly address a few of the points in the OP: > [@](#): > > \*Originally posted by Humble Servant \* > \*\*Matt Ridley, in his book, _Genome_, which I am reading with pleasure, discusses the fact that humans and chimpanzees have make-ups that, genetically, are 98% the same. Then he says [snip] . . .(I’m guessing again–but scientists show remarkably little curiosity about the reproductive isolation of our species: can we breed with chimps or not?)" > [@](#): > > [snip] . . . I still have a few questions. > > 1. Are scientists really not interested in this issue? Is Ridley correct in saying that we don’t really know that humans and chimps can’t breed? Wouldn’t the ability to interbreed be a serious issue for archaeologists attempting to establish a family tree consistent with fossil records? Does [this site](http://www.don-lindsay-archive.org/creation/mule.html) or [or this site](http://www.gate.net/~rwms/hum_ape_chrom.html) contradict Ridley?\*\* The ability to interbreed, or to produce viable hybrids, between apes and humans, is not really of any great theoretical interest. There is no question that humans and chimps are different species, by any usual definition. (Even the production of a fully-fertile hybrid would not invalidate that, according to a modern application of the biological species concept.) Genetic analysis demonstrates that the genomes are very close. However, although there is something of a correlation between the degree of genetic similarity and the ability to produce fertile/viable hybrids, that correlation is not strict. Some forms that closely similar genetically are not interfertile, and while other forms that are less similar may be perfectly fertile. Hybrid fertility/viablity may depend much more on the details of the genetic changes that have taken place, rather than simply on how many there have been. Note that the figure of “99% (or whatever) similarity” between chimps and humans refers to differences in nucleotide sequence in the genetic material. Many such subsitutions are “silent,” that is, have no effect on the protein produced by a gene, or occur in non-coding sections of the DNA. Such figures also do not take into account such important genetic changes as inversions, translocations, and chromosome fusions, etc, that can have major impacts on fertility and viability. Finally, the morphological differences between chimps and humans are most likely due to mutations in regulatory genes and/or changes in developmental pathways, in which a relatively minor genetic change can produce major changes in morphology. > [@](#): > > \*\* > 2. If chimps and humans can’t breed because of chromosomal mismatches, then how _did_ the first human-like ancestor with the problematic mutation breed with anyone (the issue **Chronos** and **Jois** were discussing)? Any further thoughts on this? I haven’t seen a definitive explanation I can understand.\*\* The difference in chromosome number between chimps and humans seems to be due to the fusion of two ape chromosomes into one human chromosome. When this first took place, the two ape chromosomes might still have been able to “pair up” somehow with the fused partner during meiosis, resulting in viable gametes. Fertility might be reduced, but occasional reproduction would still possible. Also some viable gametes could be produced just by chance. Once a few individuals with the fused chromosomes were produced, close inbreeding could preserve the change. Differences in chromosome number between closely related species is actually not that uncommon, so something like this process must happen regularly. Once a separate lineage was established, subsequent translocations and inversions in the chromosomes could prevent them from pairing up in meiosis and result in infertility. > [@](#): > > \*\* > 3. Can we assume the worst about human sexual proclivities and conclude that interbreeding is no longer possible because we would otherwise be seeing the results? (No hot monkey sex comments please.)\*\* As others have said, given human sexual proclivities we can probably assume that intercourse has sometimes taken place. But intercourse does not equate with fertilization, and fertilization does not equate with the production of a viable offspring. Production of a hybrid could be almost impossible in vivo, while quite feasible in vitro. ---
**Author:** ![Humble\_Servant](https://avatars.discourse-cdn.com/v4/letter/h/47e85d/32.png) [@Humble\_Servant](https://boards.straightdope.com/u/Humble_Servant)\ **Post date:** [March 25, 2001, 10:15pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/45 "2001-03-25T22:15:49Z")
Thanks for all the responses, especially to **Colibri** for trying to directly answer my perhaps poorly worded OP. I assure you all that my questions are serious and not prurient. > [@](#): > > \*Originally posted by Jois \* > **Chimpanzees come in 3-4 sub-species (traditionally 3, just lately someone is pressing for a 4th) and they look alike except for some fine detail, the one that comes to mind is a difference in the molars. Chimps are bought and sold by appearance. Sub-species come from different locations. If a zoo wants a 4 year old female, they might not know where she came from and if they are caging her and expecting her to mate with another of her own sub-species. Zoos are just now correcting this, partly with simple mtDNA tests on chimp hair, but now the humans are scratching their heads and wondering if the sub-species differences were enough to make the reproduction of chimps in zoos less than perfect. Were the cultural differences between the sub-species enough to account for the mamas who wouldn’t care for their offspring (not getting groups support the way they would have if they had been with their own sub-species)?** Ok, I think I need a quick primer on subspecies–given the issues with defining species **Tamerlane** and others have mentioned, how does anyone agree on subspecies? Is there a recognized body that decides what subspecies can be recognized? If subspecies are defined by geographic location and “culture,” would it ever be appropriate to classify humans by subspecies on a similar basis? (I realize how extrememly charged this question may be–I have read with interest the recent threads refuting (successfully, I thought) the idea that race can be found in human genes.) > [@](#): > > \*\* In another thread I said that there have been two news reports that said new discoveries in the fossil field will overturn evolution history (something like that) but actually it is more like 4 times in thirty days if DNA studies are counted.\*\* Which 4 reports are you referrring to? I like to try to keep up. ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [March 26, 2001, 1:14am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/46 "2001-03-26T01:14:21Z")
**Humble Servant** promises; > [@](#): > > I assure you all that my questions are serious and not prurient. Ok, as long as you promose, I’ll tell you about it. It wasn’t my fault. I was on safari and had smoked a couple bowlfuls, you see. And I decided to take a little walk by myself in the jungle. All of a sudden this pack of female bonobos jumped me and, and… well, you get the picture. Let’s just say they “knew” me, in the bibical sense. For about three days they held me captive. Fed me bananas and such. But I **didn’t** enjoy it. If there were any offspring nobody told me about it. Anybody seen any green-eyed bonobos? Peace, mangeorge ---
**Author:** ![Jois](https://avatars.discourse-cdn.com/v4/letter/j/ea666f/32.png) [@Jois](https://boards.straightdope.com/u/Jois)\ **Post date:** [March 26, 2001, 5:06am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/47 "2001-03-26T05:06:40Z")
Hi Humble Servant, I’d commented in an earlier post: “In another thread I said that there have been two news reports that said new discoveries in the fossil field will overturn evolution history (something like that) but actually it is more like 4 times in thirty days if DNA studies are counted.” To which you replied: “Which 4 reports are you referrring to? I like to try to keep up.” [http://www.independent.co.uk/news/UK/Science/2001-01/dna090101.shtml](http://www.independent.co.uk/news/UK/Science/2001-01/dna090101.shtml) Mitochondrial DNA sequences in ancient Australians: Implications for modern human origins Gregory J. Adcock, Elizabeth S. Dennis, Simon Easteal, Gavin A. Huttley, Lars S. Jermiin, W. James Peacock, and Alan Thorne PNAS 2001;98 537-542 > **[Mitochondrial DNA sequences in ancient Australians: Implications for modern...](https://www.pnas.org/content/98/2/537.abstract)** > > DNA from ancient human remains provides perspectives on the origin of our species and the relationship between molecular and morphological variation. We report analysis of mtDNA from the remains of 10 ancient Australians. These include the... “Nanjing Man” (Anything you can find.) The article rather than news reports: Hanson, B. (2001) Dating Nanjing Man. Science. 291 (5506). 947 [http://www.cnn.com/2001/TECH/science/03/21/ancient.skull.ap/index.html](http://www.cnn.com/2001/TECH/science/03/21/ancient.skull.ap/index.html) [http://dailynews.yahoo.com/h/ap/20010321/sc/ancient\_skull\_1.html](http://dailynews.yahoo.com/h/ap/20010321/sc/ancient_skull_1.html) [http://www.washingtonpost.com/wp-dyn/articles/A39106-2001Mar21.html](http://www.washingtonpost.com/wp-dyn/articles/A39106-2001Mar21.html) New York times: Skull May Alter Experts’ View of Human Descent’s Branches By JOHN NOBLE WILFORD Paleontologists in Africa have found a 3.5 million-year-old skull from what they say is an entirely new branch of the early human family tree, a discovery that threatens to overturn the prevailing view that a single line of descent stretched through the early stages of human ancestry. Science vol. 291 (no. 5508), pg. 1460, 23 Feb. 2001, Pickford and Senut have chosen to name a new genus and species for Millennium Man: _Orrorin tugenensis_. “Orrorin” apparently means “original man” in a local dialect. [http://www.boston.com/dailyglobe2/079/science/In\_China\_strange\_bronze\_heads\_rewrite\_history+.shtml](http://www.boston.com/dailyglobe2/079/science/In_China_strange_bronze_heads_rewrite_history+.shtml) That should boil down to four without the DNA article. Some are about the same topic, many newsreports have already expired, hopefully you’ll find one on each topic just the same. Jois ---
**Author:** ![Jois](https://avatars.discourse-cdn.com/v4/letter/j/ea666f/32.png) [@Jois](https://boards.straightdope.com/u/Jois)\ **Post date:** [March 26, 2001, 3:03pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/48 "2001-03-26T15:03:27Z")
I’ve bumped this up so maybe someone will answer Humble Servant’s question about species: \*\*“Ok, I think I need a quick primer on subspecies–given the issues with defining species Tamerlane and others have mentioned, how does anyone agree on subspecies? Is there a recognized body that decides what subspecies can be recognized? If subspecies are defined by geographic location and “culture,” would it ever be appropriate to classify humans by subspecies on a similar basis?” \*\* Jois ---
**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\ **Post date:** [March 26, 2001, 5:41pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/49 "2001-03-26T17:41:40Z")
Humble Servant: > [@](#): > > …how does anyone agree on subspecies? Short answer - They don’t 😃 . > [@](#): > > Is there a recognized body that decides what subspecies can be recognized? Nope 😃 . What does exist are boards that regulate nomenclature. So there is a Zoological Board of Nomenclature and a Botanical Board of Nomenclature ( which subsumes Fungi due to historical connections ). Not sure if a similar organization exists for Protists - Most likely the Zoological subsumes them ( again, for historical reasons ). These boards act solely to prevent duplication of names and to lay down rules on how the naming process is to be done. These rules can be bewilderingly complex at times, especially when it comes to minutia like designating “type” specimens ( i.e. all **species** must have an actual physical type specimen, from which the description of the species in question was based on, deposited in a museum somewhere - Hence all those drawers and drawers of preserved critters you see in museums ). There are about a dozen names for different types of “types” 😉 . Nor are the rules necessarily congruent between the two organizations I’ve named. So botanists must write up a full description in Latin when describing a new species. Zoologists need not. Duplication of scientific names in a single binomial, i.e. the Red Fox, _Vulpes vulpes_, is permitted under the zoological rules and verboten under the botanical ones. Etc. The boards also sit in judgement of questions of naming priority. If two people assign different names to the same organism, the first published name takes priority. Sometimes ( rarely ) this is amended if there is an ancient obscure name someone digs up that should have priority, but the community petitions to keep the old one to prevent confusion. I believe this happened with the _Boa constrictor_. However, what these boards don’t do, is sit in judgement of what is a valid species ( or subspecies ). That is a task of the scientific community at large. If you publish it and follow the proper procedural rules - It exists. This even goes down to self-published vanity papers. Of course if you publish in a peer-reviewed journal you are much more likely to be taken seriously ( unless you work on a very obscure group like my roomie - The major papers in his little specialty were self-published back in the 50’s and thus must be tracked down ). And of course whatever you publish is subject to revision by other scientists. And thus battle is joined 😛 . Is the Pacific Treefrog more properly included in the genus _Hyla_ or _Pseudacris_? Consensus seems to have shifted to the newer view of _Pseudacris_, but I’ve seen it go back and forth a couple of times. > [@](#): > > If subspecies are defined by geographic location, and “culture”… Subspecies are defined however you like 😃 . Isn’t this fun 😛 ? The concept of the subspecies is a much debated one. Some hardcore evolutionary biologists have little use for it, because it de facto contains no useful large-scale evolutionary info. i.e. the **ESC** is already tracking the smallest lineage on a single trajectory, the subspecies is already part of that larger trajectory. Many others however, point to its presumed utility in the field. So let’s take an example I used in a “race” thread - the salamander _Ensatina eschscholtzii_. Very common critter, with no real common name - Folks call them “Ensatina’s”. It has several subspecies, some of them markedly different in coloration. Here, in the Bay Area, we get _E. eschschotzii xanthoptica_. It’s a “classic” Ensatina body-color-wise, with the lower half of its eyeball colored a shimmery gold ( the upper half is pitch black ). North we get _E. eshsholtzii oregonensis_, which is identical, except the whole eye is black. Around Mendocino county they intergrade - the result is a critter with a black eye with a few flecks of gold 😉 . So are the differences between these two subspecies significant? Nope. They just have one tiny character that’s expressed differently and has been maintained because these aren’t outstandingly vagile critters. It probably isn’t even an adaptive character - More likely a persistent “neutral” mutation. So is it worth it to designate the two variations above as separate subspecies? You tell me - I have no idea 😃 . There is no consensus on what, exactly, constitutes a subspecies. Every taxonomist defines it differently depending on what organism they work on. Primate people may use “culture”. Are “transient” Orca’s that tend to roam nomadically and feed much more heavily on sea mammals a distinct subspecies from “resident” Orca’s that eat mostly fish? Dunno - ask a whale guy 😉 . Generally the term is used as to describe a semi-coherent population, generally with a more-or-less well-defined geographic range, that consistently exhibits some minor characteristic ( usually morphological - often color ) not found in other related populations - But these characteristics are not considered enough ( in the mind of that particular researcher ) to split them off as a separate species. So folks give it a name and make the linnaen binomial, a trinomial. Some other folks don’t bother. It’s purely a voluntary philosophical decision 🙂 . I’m not generally opposed to the idea. Another level of categorization is not a huge hindrance as long as you remember that it generally lacks evolutionary significance. It can be a handy, if imprecise, shorthand if you want to look at variation in the field and catalogue natural gene-flow, for instance. However… > [@](#): > > …would it ever be appropriate to classify humans as subspecies on a similar basis? IMNHO - **NO** Why not? Because “race” has become a politicized term and subspecies is roughly synonomous with race. Biologists sometimes use the term **race** , when referring to what other biologists refer to as **subspecies**. And both of those, are in turn, sometimes used as a synonym with **population**. Though in fact population is the most precise term, and can be used for any size group, outwardly distinct or not. Population, is, I think, a neutral enough term. We CAN refer to distinct human populations. But race in humans has been tainted by its association with the racialist ( often a synonym for racist ) notion of the classic “five races”, which, in affect, attempted to partition humans into discrete **species** ( even though this was explicitly denied ) and which completely lacked any basis in biological reality. Using subspecies, which most folks don’t grasp as the insignificant ( and often imprecise ) term that it is, brings in the word “species” and causes unnecessary confusion. For purely associative reasons I think it should be avoided. - Tamerlane ---
**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\ **Post date:** [March 26, 2001, 6:02pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/50 "2001-03-26T18:02:20Z")
Addenda to my earlier post: There is also a board that regulates the common, English names of **birds** and only birds. To the best of my knowledge it is the only one that exists for common names. So a Cinnamon Teal is always a Cinnamon Teal. Whereas a “Drum” or “Perch” might be any of a dozen different types of unrelated fish. This is why when I took Veretbrate Natural History ( but not Ornithology of course ), birds were the only group of animals we weren’t required to learn latin binomials for. As a result of that experience, to this day I know far fewer scientific names for birds 😉 . - Tamerlane ---
**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\ **Post date:** [March 26, 2001, 6:20pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/51 "2001-03-26T18:20:17Z")
Just to round out to an even 150 posts 😉 . Further comments Re: Human subspecies - Humans are so outstandingly vagile now and so overwhelmingly panmictic that the categorization of subspecies in humans is probably a useless exercise anyway. At least if you want such designations to have any predictive value. Sure we can probably delineate thousands of discrete human populations at any point in time, by sequencing data, or cultural designation, or whatever. But the borders are going to be so fuzzy, so malleable, and subject to so much rapid change through time, that all but the most isolated, endogamous populations are going to fracture and morph rapidly. By the time you assigned names to all of the human populations out there, half may have disappeared, merged or changed from there original defining parameters. Humans really ARE different from most ( all ) other animals in this regard. - Tamerlane ---
**Author:** ![Humble\_Servant](https://avatars.discourse-cdn.com/v4/letter/h/47e85d/32.png) [@Humble\_Servant](https://boards.straightdope.com/u/Humble_Servant)\ **Post date:** [March 26, 2001, 11:18pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/52 "2001-03-26T23:18:24Z")
Excellent! Superior posts, **Jois** and **Tamerlane**! Thanks for spending your 150th here. The “China strange bronze heads” report is the most elusive–I can’t find anything at all online on it. [Here is a link to an abstract on the date of Nanjing man](http://www.gsajournals.org/gsaonline/?request=get-abstract&issn=0091-7613&volume=029&issue=01&page=0027), but I couldn’t find much available on that either. The Kenyan skull and the Australian dna articles are easier to find and I had read those reports–the Leakeys are publicity machines. Just to speculate, if some unethical (“mad”) scientist was determined to try in vitro work on chimp/human dna, where do you think it would most likely occur? I.e., where are the controls/peer review/pressure most lax, but the equipment/skills most available? ---
**Author:** ![JosephFinn](https://avatars.discourse-cdn.com/v4/letter/j/3bc359/32.png) [@JosephFinn](https://boards.straightdope.com/u/JosephFinn)\ **Post date:** [March 26, 2001, 11:45pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/53 "2001-03-26T23:45:03Z")
Just for the hell of it, here is a picture of a liger named Hobbs: [http://www.sierrasafarizoo.com/animals/liger.htm](http://www.sierrasafarizoo.com/animals/liger.htm) Impressive sucker, no? Take a look at the size estimate: 800-1200 pounds, twice the size of a Siberian tiger. Let’s have a hearty “hurray” that they don’t occur naturally. From the web page: “Hobbs: Hobbs, with a mane like a lion, the long body of a tiger, and more mass than either, is a striking animal. He exhibits traits of both parents, his mother was a Bengal tigress and his father an African lion. He roars like a lion and swims like a tiger. He’s definitely all cat. He likes to play, and for all his incredible bulk he moves just as silently as any other cat.” And we have a contender in that “What Animal can Beat Another Animal?” thread… ---
**Author:** ![JosephFinn](https://avatars.discourse-cdn.com/v4/letter/j/3bc359/32.png) [@JosephFinn](https://boards.straightdope.com/u/JosephFinn)\ **Post date:** [March 26, 2001, 11:47pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/54 "2001-03-26T23:47:30Z")
And another liger (god, I love cats). These have people next to him, so you get a sense of scale: [http://www.tigers-animal-actors.com/about/liger/liger.html](http://www.tigers-animal-actors.com/about/liger/liger.html) All I can say is: “Whoah.” ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [March 27, 2001, 3:04am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/55 "2001-03-27T03:04:37Z")
One good argument against considering different groups of humans as subspecies is that there is no consistancy in the traits that one might use to classify them. Pick skin color as your basis of classification, and you group various peoples together. Pick a completely different criterion, such as Rh blood factor, and you end up lumping together another set of peoples entirely. Ditto minor but distinct things like tooth patterns, overall body build, eye folds, etc. In short, there doesn’t seem to be any group of people who have a set of_unique_ characteristics distinguishing them from the rest of humanity. As far as genetics studies go, humans seem to consist of three different kinds of Africans, and everybody else put together. ---
**Author:** ![Jois](https://avatars.discourse-cdn.com/v4/letter/j/ea666f/32.png) [@Jois](https://boards.straightdope.com/u/Jois)\ **Post date:** [March 27, 2001, 3:43am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/56 "2001-03-27T03:43:48Z")
Humble Servant, you need a [hotmail.com](http://hotmail.com) address. If you had one I’d send you the expired article. Jois ---
**Author:** ![Badtz\_Maru](https://avatars.discourse-cdn.com/v4/letter/b/e36b37/32.png) [@Badtz\_Maru](https://boards.straightdope.com/u/Badtz_Maru)\ **Post date:** [March 27, 2001, 5:54am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/57 "2001-03-27T05:54:42Z")
> [@](#): > > \*Originally posted by Lumpy \* > \*\*One good argument against considering different groups of humans as subspecies is that there is no consistancy in the traits that one might use to classify them. Pick skin color as your basis of classification, and you group various peoples together. Pick a completely different criterion, such as Rh blood factor, and you end up lumping together another set of peoples entirely. Ditto minor but distinct things like tooth patterns, overall body build, eye folds, etc. > > In short, there doesn’t seem to be any group of people who have a set of_unique_ characteristics distinguishing them from the rest of humanity. As far as genetics studies go, humans seem to consist of three different kinds of Africans, and everybody else put together. > \*\* I think the same is true of many subspecies classifications, however. Often the only distinguishing characteristics between two sub-species is one physical trait, like coloration, length of tail, etc. If humans were just another animal to us, we would probably have them divided into several subspecies. ---
**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\ **Post date:** [March 27, 2001, 9:46am UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/58 "2001-03-27T09:46:10Z")
**Badtz Maru** : Which is one reason some systematists think the use of subspecies should be abandoned 🙂 - It’s a vague device which often conveys only superficial data. But I think I should make the point, again, that humans are NOT like other animals: 1.) Humans are circum-global, and have been for a fairly long time. 2.) Humans currently have HUGE populations. 3.) Humans intergrade ceaselessly across many planes of contact - More than any other species I can think of, because of that global distribution and their penetration of every environment. 4.) Humans are the MOST vagile and adaptive species of animal ever. Birds may travel thousands of miles in a year, but any given species is restricted to certain types of habitat. Humanity has never had that restriction. 5.) As a result of the above, the same phenotype has evolved multiple times at widely separate points with similar environmental conditions. But these similar phenotypic expressions are independent of genetic relatedness, as **Collounsbury, tomndeb, Edwino** and others have repeatedly pointed out. You don’t find these sets of conditions among other animals. Over in Great Debates, **tomndeb** just made a comparison between Andaman Islanders and the people of the Congo Basin - phenotypically similar, yet genotypically distant ( relatively speaking of course ). If you attempted to classify people into “several subspecies” based on gross morphology, you’d have to group those two together. And that not only would not be informative - It would be downright obsfucatory. NO other species complex has that sort of confusion. There are very few species of animals that has widely separated populations, populations separated by numerous other populations, that express the same phenotype, but are genotypically remote. Those that are, are not placed in the same subspecies. I daresay Mexican and Indian Wolves appear somewhat similar ( smallish, adapted to hot climes ) - but they aren’t classified together. Subspecies generally do have a congruence of many genetic traits, when you bother too look at them, even if they were originally identified by morphological markers. That’s because they generally have a linear geographic distribution and aren’t being constantly penetrated and re-penetrated by different populations from different directions. Most new species probably have arisen not from immigration/emigration ( although that happens - i.e. Darwin’s Finches ), but rather from vicariance events that partition populations ( and may alter local environmental factors ). Nope - You can’t do “several subspecies” of humans. Or you can try, but it’s been discredited. That’s the classic “negroid/capoid/caucasoid/mongoloid” trap that’s been proposed before. Classifying people by skin color or the like may be a handy cultural shorthand. But it is important to realize the lack of biological grounding. What you can do is refer to the many hundreds of distinct human populations, like the Andaman Islanders, who may share a few distinct characters ( but always subject to change, the more so as modern life has accelerated the number of directions and sources of gene flow ). And I still dislike using the term “subspecies” for those populations, which I think implies to the public at large a greater permanence and separation than actually exists. - Tamerlane ---
**Author:** ![Humble\_Servant](https://avatars.discourse-cdn.com/v4/letter/h/47e85d/32.png) [@Humble\_Servant](https://boards.straightdope.com/u/Humble_Servant)\ **Post date:** [March 27, 2001, 3:12pm UTC](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163/59 "2001-03-27T15:12:22Z")
**Jois** –it’s [hservant@hotmail.com](mailto:hservant@hotmail.com) and many thanks. [Previous page](https://boards.straightdope.com/t/can-humans-and-chimps-breed/59163.md?page=2)