binkley@boulder.Colorado.EDU (Jon Binkley) (09/22/90)
In article <6284@bgsuvax.UUCP> gagen@bgsuvax.UUCP (kathleen gagen) writes: >From article <999@massey.ac.nz>, by AChamove@massey.ac.nz (A.S. Chamove): >> If chimps and humans are so close genetically, then why can we not make >> hybrids? Of course a lot of people say that we can and could. Others >> say that there are incompatibilites, but no one I have encountered has >> been able to specify what those incompatibilites are. Can you? >The chimp and man have incompatable chromosome numbers. Chimps (as well as >gorillas) have 48 chromosomes in their diploid genome whereas men have 46 >chromosomes. Ah, but horses and donkeys have different numbers of chromosomes as well. This makes their hybrids sterile, but they are viable. I don't remember the numbers and I'll try to find out. They are off by one pair, I believe, similarly to humans/apes. Of course this proves nothing; but differing chromosome numbers is not sufficient to prevent interspecies crosses. I'd bet 5 cents that a chimp/human hybrid would be viable, making humans and chimps, by definition, the same genus. I also hope I'm never proven right. -jon
binkley@boulder.Colorado.EDU (Jon Binkley) (09/22/90)
In article <26689@boulder.Colorado.EDU> I wrote: >Ah, but horses and donkeys have different numbers of chromosomes as well. >This makes their hybrids sterile, but they are viable. I don't remember >the numbers and I'll try to find out. They are off by one pair, I believe, >similarly to humans/apes. Of course this proves nothing; but differing >chromosome numbers is not sufficient to prevent interspecies crosses. Found a reference-- _An Atlas of Mammalian Chromesomes_, compiled by T.C. Hsu and Kurt Benirschke, Springer-Verlag, 1967. Donkey's have 62 (31 pairs), horses have 64 (32 pairs). Presumably two horse chromosomes are similar to one large donkey chromosome; the atlas shows their keryotypes, but I'm no cytologist. Obviously, there is sufficient homology for the chromosomes to line up properly at mitosis. Meiosis and gamete formation are screwed up though, so mules and jennies are sterile (usually). >I'd bet 5 cents that a chimp/human hybrid would be viable, making humans >and chimps, by definition, the same genus. I also hope I'm never proven >right. As I said, I'm no cytologist, but the keryotypes of horses and donkeys look less similiar to me than the keryotypes of humans and chimps, also shown in the atlas. I raise my bet to 10 cents! -jon
minsky@media-lab.MEDIA.MIT.EDU (Marvin Minsky) (09/22/90)
> Ah, but horses and donkeys have different numbers of chromosomes as >well. This makes their hybrids sterile, but they are viable. I don't >remember the numbers and I'll try to find out. They are off by one >pair, I believe, similarly to humans/apes. Of course this proves >nothing; but differing chromosome numbers is not sufficient to prevent >interspecies crosses. One of our chromosomes (I think the one called #3) is broken to from two in the chimpanzee. You'd think that in a very few years a nanotechnologist could reach into a chimp ovem and fix this or (depending on your point of view) make the corresponding anti repair in a human ovum (or sperm). Probably the human repair would be harder because you'd have to add a spindle apparatus. I am shocked by the ruthless opposition to this simple experiment. Surely it is the most vicious proto-genocide to block the coming-into-being of an entire promising new species. After all the species w've helped extinguish, this is surely the least we could do to make amends.
mmm@cup.portal.com (Mark Robert Thorson) (09/23/90)
Ah! One of my favorite subjects! I remember hearing about 10 years ago that an orangutang (or some other large primate cloesly related to humans) had been found with 46 chromosomes, and that a a group in Japan was planning to attempt a cross with a female volunteer. Anybody got any followup on that? My $0.02 says it wouldn't work, because the it isn't just the chromosome count--the type of chromosomes themselves have to be similar. As I posted many months ago, there is a little discussion of the difference between chimps and Man at the back of Stephen Jay Gould's THE MISMEASURE OF MAN. He thinks that the essential difference is neoteny, i.e. that humans are a neotenized version of an ancient ape. Neoteny is the preservation of juvenile characteristics in the adult--a sort of arrested development. This is possible explanation for things like the large head size relative to body size in humans. If the Human Genome Project is pushed to completion, it has the potential to discover such "clocks" in the genetic programming of growth. This would potentially make possible the development of super-humans, with exagerrated neoteny, and proto-humans, with retarded neoteny. It might also lead the way toward the neotenization of inferior species, such as chimps, to increase their intellectual capacity. This is indeed the most important scientific endevour ever conceived. It has the potential to improve not merely Man's knowledge, but Man himself. An increase in Man's mental abilities is like a multiplier which could be applied to all future achievements of Man. No other breakthrough could provide benefits of such enormous and lasting value. To shrink from this experiment is the greatest disservice we can provide to future generations. Destiny demands it! The future heroes of science will be those brave men and women (and perhaps a few smart chimps) who can see past the "morality" composed by the clique of small-brained bureaucrats who make the guidelines required to receive government funding.
drbob@hpuxa.ircc.ohio-state.edu (Robert H. Woodman) (09/23/90)
In article <34196@cup.portal.com> mmm@cup.portal.com (Mark Robert Thorson) writes: <stuff about crossing an orangutang and a human deleted> > >As I posted many months ago, there is a little discussion of the difference >between chimps and Man at the back of Stephen Jay Gould's THE MISMEASURE >OF MAN. He thinks that the essential difference is neoteny, i.e. that >humans are a neotenized version of an ancient ape. Neoteny is the >preservation of juvenile characteristics in the adult--a sort of arrested >development. This is possible explanation for things like the large head >size relative to body size in humans. Gould is going long on speculation here. "Proof" of this speculative statement is tenuous at best. The fact that neotany exists is interesting but it neither means nor proves that the human is a neotanized version of the ancient ape. >If the Human Genome Project is pushed to completion, it has the potential >to discover such "clocks" in the genetic programming of growth. This would >potentially make possible the development of super-humans, with exagerrated >neoteny, and proto-humans, with retarded neoteny. It might also lead the way >toward the neotenization of inferior species, such as chimps, to increase >their intellectual capacity. (1) The human genome project, in its present incarnation, is a waste of money and talent. It ought to be either scaled back drastically or even axed completely until there is a steady commitment for "small science," with money left over for "big science" projects. (2) The idea that you project, species engineering, is frightening, grossly unethical, and just plain wrong. Without adequate safeguards, such work can conceivably lead down the path of creating inferior species of humans (or superior species of lesser primates) which can then be- come slaves of "superior" humans. Such an action is definately on ethically unstable foundations (at best). If you claim to have cre- ated an inferior human, you have the problems of human slavery. If you have created a superior chimp, you likely have cruelty to animals. How do you propose to protect such creatures? And why, be- yond scientific mountain-climbing (e.g. Why did Sir Edmund Hillary climb Mt. Everest? Because it was there.) do you propose to en- gineer such species? You have not stated any ethically noble purpose; therefore, your proposal, as it stands, is ethically invalid. I would point out that, in the United States, science depends on public trust and acceptance of what is being done. It isn't easy to conduct experiments which correct genetic defects such as ADA deficiency (which leads to SCID), because there is a public mistrust of scientists, and because scientists all too often (IMO) pursue the science with a cursory nod (at best) to the ethics. It is a fearsome thing to be supported by public trust, and experiments such as yours demand the highest attention to public trust. >This is indeed the most important scientific endevour ever conceived. It has >the potential to improve not merely Man's knowledge, but Man himself. >An increase in Man's mental abilities is like a multiplier which could be applied >to all future achievements of Man. No other breakthrough could provide >benefits of such enormous and lasting value. Pure speculation with no proof. And what improvements would you make? Or would you rather *I* decide? Or maybe we should let some religious leader decide? Maybe we could delete the genes that program for conservatism? How about liberalism? Maybe we could delete the genes for homosexuality? or how about including genes that make every- one bisexual? You're treading on ethically thinner and thinner ice. >To shrink from this experiment is the greatest disservice we can provide >to future generations. Destiny demands it! The future heroes of science >will be those brave men and women (and perhaps a few smart chimps) who can >see past the "morality" composed by the clique of small-brained bureaucrats >who make the guidelines required to receive government funding. You don't suppose that "small-brained bureaucrats" might consider themselves beholden to the morality of the public which pays taxes and votes, do you? As I've already said, science in the United States (no make that the Western world) rests on support by the public. Until you wake up to that, and realize that what you've have so glibly proposed amounts to bureaucratic dictation of moral standards (or at least a dictate that public morality is irrelevant to scientific pursuits), you will most likely be continually frustrated in your desire for species engineering. As for me, though I work in the area of molecular biology, I feel that the use of the tools and techniques of my trade for the purpose of species engineering of higher animals is wrong, at least at this time, because the ethical foundation to do such work has not been laid properly. Conducting science in a ethical vacuum (partial or com- plete vacuum is irrelevant) is a prescription for either future catas- trophe or a future shutdown of science by an outraged public. -=- ********************************************************************* *Bob Woodman * "A job not worth doing well is not * *INTERNET: woodman.1@osu.edu * worth doing."--Salvador Luria * *********************************************************************
sticklen@cps.msu.edu (Jon Sticklen) (09/23/90)
From article <4904@nisca.ircc.ohio-state.edu>, by drbob@hpuxa.ircc.ohio-state.edu (Robert H. Woodman): <a lot of stuff deleted...> > .... Conducting science in a ethical vacuum (partial or com- > plete vacuum is irrelevant) is a prescription for either future catas- > trophe or a future shutdown of science by an outraged public. > .... I sympathize with Woodman's thurst, but the conclusion is very circular. What constitutes "ethical vacuum" for a particular research direction? To avoid this horrible state (ethical vacuum) what can I do? a) Do I have to know what my results are going to be, then consider the ethical implications of those results, then NOT do the experiment if the implications are somehow not meeting my ethical standards? Most scientists would claim you cannot do that because you cannot know what experiemntal results will be in any a priori way. b) So if (a) will not work, then should I go on and do experiemnts in which results are not certain, but if the results are not meeting my "ethical standards" maybe I should suppress the results? Somehow that does not sound too scientific either. So what should a scientist do? ---jon---
AChamove@massey.ac.nz (A.S. Chamove) (09/25/90)
I agree that the unequal chromosome numbers would not preclude a chimp-human hybrid. A primatologist (Chiarelli) collected monkey hybrids and there were a number with different chromosome numbers. I remember reading a book called THE MURDER OF THE MISSING LINK (fiction) years ago. The premise was as follows: that someone had crossed a chimp with a human, and to determine its "true" (legal) nature, he had killed it. Most of the book was concerned with the trial--was he guilty of murder? arnold
mls@cbnewsm.att.com (mike.siemon) (09/26/90)
In article <3432@media-lab.MEDIA.MIT.EDU>, minsky@media-lab.MEDIA.MIT.EDU (Marvin Minsky) writes: > Surely it is the most vicious proto-genocide to block the > coming-into-being of an entire promising new species. After all the Well, now; *that's* a loaded term for you, "proto-genocide" -- we are to be held to account as murderers of the worst kind for NOT producing species we might conceivably produce? Isn't that the old-time Catholic argument against birth-control? > species w've helped extinguish, this is surely the least we could do > to make amends. And here is the real rub. Your position assumes as a default that we are "good guys" enough to do an acceptable job of "guardianship" over any such manufactured species. I have doubts -- very serious doubts -- that this is a good assumption. Particularly when I see language like Mr. Thorson's: # potentially make possible the development of super-humans ... # and proto-humans... It might also lead the way toward the neotenization # of inferior species, such as chimps... # future generations. Destiny demands it! The future heroes of science # will be those brave men and women (and perhaps a few smart chimps) who can # see past the "morality" composed by the clique of small-brained bureaucrats The last major usage of such terms (untermensch und uebermensch, and the mentality that sees the world in terms of "inferiority" and its own "superiority" to the demands of human morality has sufficiently brought the terms into disrepute that any *contemporary* advocacy of such things had damn well better be prepared to give a good and compelling defense for pulling out those particular stops on the rhetorical organ. "Destiny demands it" indeed! And yes, I *am* calling proponents of such experiments (potential) Nazis, unless they can propose truly adequate controls to prevent moral abuses. And given that we have a bad record of providing such controls within our *own* species, you've got a daunting task. -- Michael L. Siemon "O stand, stand at the window, m.siemon@ATT.COM As the tears scald and start; ...!att!sfsup!mls You shall love your crooked neighbor standard disclaimer With your crooked heart."
sbishop@desire.wright.edu (09/26/90)
In article <26700@boulder.Colorado.EDU>, binkley@boulder.Colorado.EDU (Jon Binkley) writes: > In article <26689@boulder.Colorado.EDU> I wrote: > >>Ah, but horses and donkeys have different numbers of chromosomes as well. >>This makes their hybrids sterile, but they are viable. I don't remember >>the numbers and I'll try to find out. They are off by one pair, I believe, >>similarly to humans/apes. Of course this proves nothing; but differing >>chromosome numbers is not sufficient to prevent interspecies crosses. > > Found a reference-- _An Atlas of Mammalian Chromesomes_, > compiled by T.C. Hsu and Kurt Benirschke, Springer-Verlag, 1967. > > Donkey's have 62 (31 pairs), horses have 64 (32 pairs). Presumably > two horse chromosomes are similar to one large donkey chromosome; > the atlas shows their keryotypes, but I'm no cytologist. > > Obviously, there is sufficient homology for the chromosomes to > line up properly at mitosis. Meiosis and gamete formation are > screwed up though, so mules and jennies are sterile (usually). > >>I'd bet 5 cents that a chimp/human hybrid would be viable, making humans >>and chimps, by definition, the same genus. I also hope I'm never proven >>right. > > As I said, I'm no cytologist, but the keryotypes of horses and donkeys > look less similiar to me than the keryotypes of humans and chimps, also > shown in the atlas. I raise my bet to 10 cents! > > -jon Could some of the biologists out on the net comment on this? I found it of great interest. If you can explain why chimp/man would not be inter-fertile then please do so. And in layman's terms, please. If keryotypes are simular what would need to be dissimular to prevent conception? I also am willing to consider immunological responses on the part of the host mother.
mmm@cup.portal.com (Mark Robert Thorson) (09/27/90)
mls@cbnewsm.att.com (mike.siemon) says: > The last major usage of such terms (untermensch und uebermensch, and the > mentality that sees the world in terms of "inferiority" and its own > "superiority" to the demands of human morality has sufficiently brought > the terms into disrepute that any *contemporary* advocacy of such things > had damn well better be prepared to give a good and compelling defense > for pulling out those particular stops on the rhetorical organ. > > "Destiny demands it" indeed! And yes, I *am* calling proponents of such > experiments (potential) Nazis, unless they can propose truly adequate > controls to prevent moral abuses. And given that we have a bad record > of providing such controls within our *own* species, you've got a daunting > task. This is the typical -- 100% emotional -- argument always presented by the opponents of genetic experimentation. It's always NAZIS, NAZIS, NAZIS !!! Even simple stuff like fixing a broken gene or implanting a few fetal brain cells brings the would-be Jeremy Rifkins out of the woodwork. What particular "moral abuses" do you have in mind? Does the idea of human/ape sex repel you? Don't worry! No one's likely to nominate you to participate in the great experiment! Only the fittest DNA will do! Is it the idea the manufactured species would be exploited? Are horses exploited? Are dogs and cats exploited? If this technology could produce a companion animal to man -- something like a dog, but 10 times better in every way -- that would be an invention, a blessing, comparable to fire or the wheel. Is it fear that the manufactured species would be superior to us, would replace us? If so, I'm entirely in favor of it! If we are so easy to replace, we should be replaced! If man is obsolete, he should be extinct! That's evolution, pal! If you can't stand the heat, get out of the gene pool! I would feel greatly honored in helping to pass on the torch of science to a superior replacement species. And I wouldn't mind admitting a bit of race-pride if that replacement species had at least 90% of human DNA. Much better than bestowing such an inheritance on a metallosilicon robot or a Mason jar full of nanocomputers.
minsky@media-lab.MEDIA.MIT.EDU (Marvin Minsky) (09/27/90)
In an earlier note, I said: >> Surely it is the most vicious proto-genocide to block the >> coming-into-being of an entire promising new species. mls@cbnewsm.att.com replies > Well, now; *that's* a loaded term for you, "proto-genocide" -- we are > to be held to account as murderers of the worst kind for NOT producing > species we might conceivably produce? Isn't that the old-time Catholic > argument against birth-control? Well, yes -- and I meant it as a mixture of irony, sarcasm, and humor. Why does that argument stop before asserting that our job is to produce as many humans as possible? But I was trying to be a little more serious in sugeesting that after extinguishing so many species, making some new ones is >> surely the least we could do to make amends. Then mls@cbnewsm expressed reservations about this: > And here is the real rub. Your position assumes as a default that we > are "good guys" enough to do an acceptable job of "guardianship" over > any such manufactured species. I have doubts -- very serious doubts > -- that this is a good assumption. and quite properly countered some of my "loaded" terminology with more of his own. But there is a serious issue: 'unfit' as we may presently be to plot the future of biology, we should try to clarify the issues as well as we can, and recognize that the responsibility remains with us no matter that we turn from it. In particular, we are responsible for the chimpanzees and for their further evolution. They are our closent relatives. Much like us, their brains may well have evolved quite as much as ours have, in the five megayears since the divergence, and the unknown refinements therein could be, in our own future, the most valuable biological treasurehouse on the planet. How could that be? The human brain is composed of several hunderd specialized sub-computers of different architectures. They each have different features and bugs. (Never mind that one man's bug is another man's feature -- that's evolution.) Now chimpanzees must have evolved quite a few different micro-arrangements, and these could be the source of cognitive powers different from ours, if suitable combined. It is the same argument, perhaps, for preserving the botanical variety for future medical interventions, to preserve the genetic variety of our relatives for future mutual needs. Some millenia from now, we might find that a few chimp genes could provide some of our descendants with ways around some of our own limitations to learning and thinking. So the hybridization proposals might well be premature, but the important thing is to get the world to recognize the immense importance of helping our relatives. But, unfortunately, to even discuss such things can sometimes do more harm than good.
binkley@boulder.Colorado.EDU (Jon Binkley) (09/28/90)
In article <34305@cup.portal.com> mmm@cup.portal.com (Mark Robert Thorson) writes, in response to Michael Siemon: >Even simple stuff like fixing a broken gene or implanting a few >fetal brain cells brings the would-be Jeremy Rifkins out of the woodwork. Precisely. And if beneficial genetic research brings out the anti-technology troglodytes in droves, what do you think the kind of research you're proposing would do? What it would do is bring on such a backlash that no more valuable research would be performed. Science doesn't operate in a social vacuum. >What particular "moral abuses" do you have in mind? Does the idea of >human/ape sex repel you? Don't worry! No one's likely to nominate you >to participate in the great experiment! Only the fittest DNA will do! Good Mark. Glad to see you're so much less emotional than Michael. -Jon Binkley
binkley@boulder.Colorado.EDU (Jon Binkley) (09/28/90)
Since in article <1297.270090e2@desire.wright.edu>, sbishop@desire.wright.edu took the time to repost my chromosome number articles, I'll take the time to correct them. I wrote: >> Obviously, there is sufficient homology for the chromosomes to >> line up properly at mitosis. Meiosis and gamete formation are >> screwed up though, so mules and jennies are sterile (usually). It was pointed out to me in e-mail by Jeff Haemer that chromosomes don't line up in mitosis, so homology is not important (at least as far as chromosome segregation is concerned). sbishop@desire.wright.edu writes: >Could some of the biologists out on the net comment on this? I found it of >great interest. If you can explain why chimp/man would not be inter-fertile >then please do so. And in layman's terms, please. If keryotypes are simular >what would need to be dissimular to prevent conception? I also am willing to >consider immunological responses on the part of the host mother. I would like to comment that I don't consider immunological responses a barrier to interspecies crosses. The mother's immune system is no more likely to attack the developing hybrid than it would a child of her own species. Someone mentioned the response to Rh+; remember, this response rarely occurs in the first Rh+ pregnancy of an Rh- mother. This is because the mother's and child's blood do not come into direct contact until birth. At this time, the mother develops anti-Rh antibodies, and subsequent Rh+ pregnancies are affected. Since there are now several people named Jon responding to this line, I'd like to restate that while I think chimp/human hybridization is possible, I believe that under no circumstances should it be done. Certain people have equated this with being anti-technology in general. I'm not; in fact I work in a lab that does the type of things that make Luddites like Rifkin cringe. Nor am I generally opposed to animals being used for experiments. However, since I obviously believe chimps to be members of my own genus, I feel they should be left alone from human experimentation. Yes, kids, even for AIDS research. -Jon Binkley
AChamove@massey.ac.nz (A.S. Chamove) (09/28/90)
It is possible that if a chimp-human hybrid was born, that the category of chimp would be reconsidered. IT just might mean that chimps would no longer be used for hepititus and AIDS research, and that zoo conditions would be re-evaluated for these "animals." When chimps were taught sign-language, some of this took place. OF course others just said "IT was not really language and chimps are just animals." arnold
mvp@hsv3.UUCP (Mike Van Pelt) (09/29/90)
It seems to me that some of the more abstract questions involved could
be examined, without treading into the thorny moral and ethical
problems, by trying {chimp,gorilla,orangutan,gibbon; pick two}
crosses. Has this been tried? If so, it probably wasn't sucessful.
Any data?
--
Mike Van Pelt
Headland Technology/Video 7 Use a pun, go to jail.
...ames!vsi1!v7fs1!mvpdmark@acsu.buffalo.edu (David Mark) (09/29/90)
In article <5042@hsv3.UUCP> mvp@hsv3.UUCP (Mike Van Pelt) writes: >It seems to me that some of the more abstract questions involved could >be examined, without treading into the thorny moral and ethical >problems, by trying {chimp,gorilla,orangutan,gibbon; pick two} >crosses. Has this been tried? If so, it probably wasn't sucessful. >Any data? Such data, if they exist, would not be definitive. I recall (I hope correctly) that recent biochemical work suggests that the Homo sapiens is the closest living relative of the chimps (Pan), and that human-chimp are genetically the closest pair among great apes of different genera. So even if it were the case that probablilty of successful hybridization were a monotonic function of genetic distance (and I bet it is more complicated than that!), a lack of successful inter- generic hybrids among other pairs of great apes would not really indicate that human-chimp hybrids are unlikely. However, successful hybridization between any other pair would suggest (but not prove) that the viability of chimp-human would be reasonably likely. David Mark dmark@acsu.buffalo.edu
davidp@dbrmelb.dbrhi.oz (David Paterson) (10/02/90)
I very much doubt if a direct hybrid is possible. Having seen humans who have just a bit of genetic material out of place it seems clear that there is much too great a genetic difference between humans and chimps. Human male and female genotypes are able to be so different only because one of the the two 'X' chromosomes is deactivated in women and the male 'Y' chromosome is remarkably devoid of active genes. BUT: It is technically possible to create a creature that is physiologically indistinguishable from a chimp and genetically compatible with a human. This would be done by moving large chunks of genetic material around on the chimp chromosomes and changing the number of chromosomes. (Basically by the process of matching one chimp gene to one human gene). BUT: Such a creature would never be created for ethical reasons. BUT: I would like to see the creation of a creature that is as close as possible to the common ancestor of chimps and humans. Although we may never be able to determine the exact genetic makeup of such a greature it should be possible to ensure that 99.9% of the genes are correct. ----------------------------------------------------------------------------- David Paterson, CSIRO Division of Building, Construction and Engineering, PO Box 56, Highett, Victoria, 3190, AUSTRALIA AARNet/Internet: davidp@mel.dbce.csiro.au ACSNet: davidp%dbrmelb.dbrhi@munnari.oz.au
jcarden@pawl.rpi.edu (Jeffrey R Carden) (10/03/90)
Has anyone else seen the BBC mini-series, First Born, based on the novel Gor Saga, by Maureen Duffy? The three part series has shown up on A&E a couple of times and is about a gorilla/man hybrid. It's pretty interesting, there's very little scientific detail, but it does get into the ethics of the situation somewhat. One interesting thing I noticed as I was skimming through the first part was that the scientist responsible thinks of the hybrid as a new species with man's intelligence without his homicidal agression while the military person in charge of the experiment sees organ transplants, space explorers, and super-warriors.
sparks@druwy.ATT.COM (SparksAE) (10/03/90)
In article <5042@hsv3.UUCP>, mvp@hsv3.UUCP (Mike Van Pelt) writes: > It seems to me that some of the more abstract questions involved could > be examined, without treading into the thorny moral and ethical > problems, by trying {chimp,gorilla,orangutan,gibbon; pick two} > crosses. Has this been tried? If so, it probably wasn't sucessful. > Any data? > -- > Mike Van Pelt Why would this remove "the thorny moral and ethical problems"? Some of these primates (chimpanzees anyway) are close enough genetically to humans that the question of hybrids with humans has, on this forum, been considered a reasonable question to pose and discuss. Is it consistent to believe that they do not deserve similar (to humans) moral/ethical consideration? Alan Sparks
sarima@tdatirv.UUCP (Stanley Friesen) (10/03/90)
In article <38212@eerie.acsu.Buffalo.EDU> dmark@acsu.buffalo.edu (David Mark) writes: >Such data, if they exist, would not be definitive. I recall (I hope >correctly) that recent biochemical work suggests that the Homo sapiens >is the closest living relative of the chimps (Pan), and that human-chimp >are genetically the closest pair among great apes of different >genera. It is, unfortunately, not so simple. There are some immuno-compatibility results which, if interpreted naively, suggest that humans and chimps are the closest pair. Some other DNA based studies have produced similar results. However, there are other studies, and other approaches to relatedness which make the chimp-gorilla pair the closest. For instance - chimps and gorillas both use knuckle-walking on the ground, but even the earliest Hominids (such as Lucy) show *no* trace of knuckle-walking. This suggests a shared common ancestor between chimps and gorillas not shared with humanity. The problem with the DNA distance results is that the most commonly cited studies fail to indicate the standard error values for the measurements. When this deficit is corrected, the distinctions amoung chimps, gorillas, and humans are statistically insignificant. (That is the branching sequence is indeterminate). So, for all proctical purposes gorillas, chimps and humans are about equally related to one another. >a lack of successful inter- >generic hybrids among other pairs of great apes would not really indicate >that human-chimp hybrids are unlikely. However, successful hybridization >between any other pair would suggest (but not prove) that the viability of >chimp-human would be reasonably likely. Also quite true, though for different reasons. Hybridization may depend on other things besides genetic difference, such as physical differences. -------------------- uunet!tdatirv!sarima (Stanley Friesen)