mrh@cybvax0.UUCP (Mike Huybensz) (12/09/86)
This doesn't belong in talk.politics: followups to talk.origins. While I am well convinced of evolution, there are a few commonly repeated claims which need to be debunked. In article <635@argus.UUCP>, ken@argus.UUCP (Kenneth Ng) writes: > How about that moth that turned black in response to increased air > pollution, and turned gray again in response to air pollution controls? This is THE most often repeated claim of natural selection in action. Industrial melanism of the Pepper Moth is widely repeated in textbooks (which are notorious for the propagation of old, refuted, or pseudo "facts".) However, at a seminar given by Dr. Ted Sargent (one of the foremost experts on predation and color variation within populations of moths), he claimed that the original study was invalid on a host of methodological grounds. The most memorable criticism was that nobody had actually witnessed predation of a wild moth by a bird. While experiments have demonstrated the plausibility of the concealment/predation hypothesis both in the lab and in the forest, it just hasn't been observed in nature. Other problems included sampling biases according to collector and locality. Current research on Biston betularia (the Pepper Moth) seeks to remedy these problems, but it would be difficult to repeat the "experiment" without another industrial revolution. This news makes a good measure of who does and doesn't have a scientific attitude towards evolution. If you can't let go of a cherished belief in the face of evidence, you're not taking a scientific attitude. I'm happy to say that at the Cambridge Entomological Society meeting where this was discussed, alot of people were distraught, but none seemed to reject the position. Unfortunately, I don't think this news has been published yet. Dr. Sargent has made no secret of it, and it is widely known within research circles, but I think he is gathering information to make a definitive statement. > How would you explain the increased resistance to DDT from insects? This is a good example of artificial selection (no more natural than industrial melanism of the pepper moth.) There is a vast scientific literature on increasing resistance to pesticides. Crop pests develop resistance to most pesticides within 3 to 10 years, creating a sort of biochemical arms race between the chemical companies and the pests. In article <189@cpro.UUCP> asgard@cpro.UUCP (J.R. Stoner) writes: > And how about the evolution of Haike crabs in Japan. It has been seen that > these remarkable creatures evolved (with carapaces with likenesses of samurai > on them) within recorded history. Legends say these crabs are the souls of > warriors who drowned in the bay after a failed sea battle. Fishermen would > routinely throw back into the water any crab that had any semblence to a > warrior. In the course of time a whole new species appeared with _very_ > good images of recognizable japanese faces on their carapaces. This sounds like a pretty little just-so story to me. It should be possible to gather good evidence of this, perhaps from shell middens, or by comparing populations that have been selected with populations that haven't. I doubt that such evidence exists. How can we observe current evolutionary change? The very first thing we need is baseline data. You can't say change has occurred unless you can make a comparison. For the near future we will have difficulty, because there are few "before" samples (other than fossils) that we can use for comparisons. In the intermediate distant future, we will be able to compare populations that were introduced to islands with baseline data being collected right now. -- "Enough of acting the infant who has been told so often how he was found under a cabbage that in the end he remembers the exact spot in the garden and the kind of life he led there before joining the family circle." Samuel Beckett -- Mike Huybensz ...decvax!genrad!mit-eddie!cybvax0!mrh
mrh@cybvax0.UUCP (Mike Huybensz) (12/09/86)
Followups to sci.bio and talk.origins (definitely not the kids newsgroups!) In article <2778@gitpyr.gatech.EDU> dts@gitpyr.UUCP (Danny Sharpe) writes: > I've heard that, due to lawnmowers, dandelions in suburban areas are being > selected for shorter stems. This is probably not true. The last I read about it (about 12 years ago), our common weed dandelion is thought to be entirely one clone. Its seeds are produced apomicticly: a somatic cell becomes the embryo. The great variation of form we see in dandelions is not genetic, but developmental. It is possible for sports (mutations within clonal lines) to occur, but I don't know of any research identifying sports in dandelions. > And then there's all the diseases that have become > resistant to the drugs used to treat them. Yes, this is a good example of selection. > These are all examples of natural selection at work. Neither of these is natural selection, in that the selection pressures are being applied by man. -- "I have yet to see any problem, however complicated, which, when you looked at it the right way, did not become still more complicated." Poul Anderson -- Mike Huybensz ...decvax!genrad!mit-eddie!cybvax0!mrh
mrh@cybvax0.UUCP (Mike Huybensz) (12/09/86)
Followups to sci.bio and talk.origins. In article <2849@bu-cs.BU.EDU> bzs@bu-cs.BU.EDU (Barry Shein) writes: > For what it's worth I believe the acid test of a new species is that > it is no longer able to breed with the original species it evolved > from. Morphological changes alone aren't sufficient (until which time > those changes prevent inter-breeding.) What you believe is irrelevant. :-) The fact is that biologists cannot decide what constitutes a species. Many will tell you that species are really fictions. But useful fictions. Different criteria are used to decide what species are in different taxa (groups of organisms). This isn't due to the fact that different workers have different opinions. It's due to the fact that no single definition is useful for all taxa. The complications arising from the diversity of organisms and the sources of that diversity make your test impractical. First, there is the temporal question: is a species today really the same species that existed X years ago? How can we test if the ancestral species has died out? What if hybridization is possible but the progeny are less fit (or even sterile)? Say hybridization can occur in the lab but doesn't in nature? Because of distance? Because of different pollinators? Because of different behavior? What about continuously interbreeding populations whose members at opposite extremes of the range can't interbreed? What about parthenogenetic organisms? Is every one of them a species? -- "People always HAVE eaten people; people always WILL eat people. You can't change human nature!" (From "The Reluctant Cannibal" on the Flanders and Swann album "At The Drop Of A Hat".) -- Mike Huybensz ...decvax!genrad!mit-eddie!cybvax0!mrh
krs@astroatc.UUCP (12/10/86)
In article <1260@cybvax0.UUCP> mrh@cybvax0.UUCP (Mike Huybensz) writes: >Followups to sci.bio and talk.origins (definitely not the kids newsgroups!) > >In article <2778@gitpyr.gatech.EDU> dts@gitpyr.UUCP (Danny Sharpe) writes: ... > >Yes, this is a good example of selection. > >> These are all examples of natural selection at work. > >Neither of these is natural selection, in that the selection pressures are >being applied by man. So what? The mechanism is the thing in question, not the cause of the evolutionary pressure. That man can reproduce the result is proof of the theory.
wlin@princeton.UUCP (William Lin) (12/10/86)
In article <1260@cybvax0.UUCP> mrh@cybvax0.UUCP (Mike Huybensz) writes: >In article <2778@gitpyr.gatech.EDU> dts@gitpyr.UUCP (Danny Sharpe) writes: >> These are all examples of natural selection at work. > >Neither of these is natural selection, in that the selection pressures are >being applied by man. I fail to see why pressures applied by man, which is a creature of nature, should by deemed 'not natural'. Bill Lin (wlin@princeton.UUCP) Department of Computer Science Princeton University
mrh@cybvax0.UUCP (Mike Huybensz) (12/11/86)
In article <2280@princeton.UUCP> wlin@princeton.UUCP (William Lin) writes: > In article <1260@cybvax0.UUCP> mrh@cybvax0.UUCP (Mike Huybensz) writes: > >Neither of these is natural selection, in that the selection pressures are > >being applied by man. > > I fail to see why pressures applied by man, which is a creature of nature, > should by deemed 'not natural'. I agree with you, however the hoary old human/natural dichotomy (which has no place in science) is important to Christian (often) and some other philosophies. If we want to convince them of our positions, we can still do it by adopting the slight restiction. After that, we can undertake the much more difficult task of convincing them that humans are natural too, contrary to their philosophy. (In cladistic terms, human is a derived group of natural, not a sister group to natural.) Another poster asked why the distinction between artificial selection and natural selection mattered, since the mechanism is the same. The problem is that artificial selection does not constitute proof of natural selection. Otherwise, one might just as well say that because man has demonstrated locomotion by internal combustion, other organisms locomote by internal combustion. -- "Historians will have to face the fact that natural selection determined the evolution of cultures in the same manner as it did that of species." Konrad Lorenz in "On Agression" 1966. -- Mike Huybensz ...decvax!genrad!mit-eddie!cybvax0!mrh
michaelm@bcsaic.UUCP (Michael Maxwell) (12/11/86)
In article <2849@bu-cs.BU.EDU> bzs@bu-cs.BU.EDU (Barry Shein) writes: > For what it's worth I believe the acid test of a new species is that > it is no longer able to breed with the original species it evolved > from... I've always thought this definition, if *strictly* applied, rather humerous. All males must be of separate species from each other, since they can't interbreed (and likewise all females)...:-) -- Mike Maxwell Boeing Advanced Technology Center arpa: michaelm@boeing.com uucp: uw-beaver!uw-june!bcsaic!michaelm
scott@hou2g.UUCP (12/12/86)
In article <1260@cybvax0.UUCP>, mrh@cybvax0.UUCP (Mike Huybensz) writes: > > And then there's all the diseases that have become > > resistant to the drugs used to treat them. > > Yes, this is a good example of selection. > > > These are all examples of natural selection at work. > > Neither of these is natural selection, in that the selection pressures are > being applied by man. Sorry Mike, but that's one of the biggest pieces of shit I've read in this group in some time. It also betrays a dangerous arrogance about the relationship between "man" and "nature". Just why do you consider man as being outside of (or is it above?) nature? The diseases' environment has changed. The organisms better adapted to the new environment have survived. The ones that are not suitable have not. That is natural selection. ========================================= "Nonetheless, keeping an open mind shouldn't be synonymous with keeping one that's just plain empty." Scott J. Berry ihnp4!hou2g!scott
slk@mit-vax.UUCP (Ling Ku) (12/12/86)
In article <1260@cybvax0.UUCP> mrh@cybvax0.UUCP (Mike Huybensz) writes: >Followups to sci.bio and talk.origins (definitely not the kids newsgroups!) >> And then there's all the diseases that have become >> resistant to the drugs used to treat them. > >Yes, this is a good example of selection. > >> These are all examples of natural selection at work. > >Neither of these is natural selection, in that the selection pressures are >being applied by man. > >Mike Huybensz ...decvax!genrad!mit-eddie!cybvax0!mrh Why is there any difference, whether the selection is due to "nature" (like temperature, amount of sunlight etc) or due to "human" in the form of mass killings or change of natural environment? As long as the human race is continue going to affect the environment in a certain way, then it seems any selection pressures we put on the environment has the same effect as "natural" selection. Siu-Ling
werner@aecom.UUCP (Craig Werner) (12/14/86)
It was basically decided a prerequisite for posting to net.sci
(or whatever we're calling ourselves these days) was a belief that
evolution was real and that creationism should be relegated to talk.origins.
However, as long as the rule has been breached. Allow me to share
a letter of mine that the New York Daily News actually published on their
Op-Ed page:
The following appeared in the Letters to the Editor page
of the New York Daily News on Sat. Nov 22, 1986. The
Science Lesson
Bronx: About Cal Thomas' col-
umn "Let's teach both fact and
fiction" on creationism and
evolution: He subtly implies
that it is evolution that is the
fiction. Evolution is incon-
trovertible fact. It is only the
explanations of it mechanisms
that are theories. He is wrong in
saying that the court of public
opinion should decide which is
right. In science, there is only
one standard: the weight of the
evidence. And although the evi-
dence is incomplete regarding
evolution, it completely rules
out a creationist scenario.
Craig Werner, Albert Einstein
College of Medicine
--
Craig Werner (MD/PhD '91)
!philabs!aecom!werner
(1935-14E Eastchester Rd., Bronx NY 10461, 212-931-2517)
"But I digress..."gallagher@husc4.harvard.edu (paul gallagher) (12/14/86)
In article <9@bcsaic.UUCP> michaelm@bcsaic.UUCP (Michael Maxwell) writes: >In article <2849@bu-cs.BU.EDU> bzs@bu-cs.BU.EDU (Barry Shein) writes: >> For what it's worth I believe the acid test of a new species is that >> it is no longer able to breed with the original species it evolved >> from... > >I've always thought this definition, if *strictly* applied, rather humerous. >All males must be of separate species from each other, since they can't >interbreed (and likewise all females)...:-) Actually, the definition of biological species (originated by Ernst Mayr) states that two individuals are of different species if they belong to *populations* which are reproductively isolated. Any sexually reproducing population has both males and females. However, although males need females, females don't neccessarily need males. Under laboratory conditions, the ovum of the female of some species can be artificially induced to begin development, without need of sperm. I read one author who, noting that many women have given birth without ever apparently having had sex, thinks that virgin birth is possible in humans. Paul Gallagher
chiaraviglio@husc2.UUCP (lucius) (12/15/86)
In article <889@husc6.UUCP>, gallagher@husc4.harvard.edu (paul gallagher) writes: > I read one author who, noting that many women have given birth without > ever apparently having had sex, thinks that virgin birth is possible in > humans. This seems very unlikely, because artificial stimulation of a mammalian egg causes development to occur only up to a certain point (gastrulation I think), after which it always becomes abnormal, and cannot proceed further. As far as I know, the reason for this is not known; it works fine in many other organisms, and even occurs naturally in some (such as some lizards, which are near the same evolutionary path as mammals, although not as advanced (mammals evolved from reptiles)). The more likely explanation is too obvious to be worth mentioning. -- -- Lucius Chiaraviglio lucius@tardis.harvard.edu seismo!tardis!lucius Please do not mail replies to me on husc2 (disk quota problems, and mail out of this system is unreliable). Please send only to the address given above.
beth@sphinx.UUCP (12/16/86)
In article <1260@cybvax0.UUCP> mrh@cybvax0.UUCP (Mike Huybensz) writes: >In article <2778@gitpyr.gatech.EDU> dts@gitpyr.UUCP (Danny Sharpe) writes: >> I've heard that, due to lawnmowers, dandelions in suburban areas are being >> selected for shorter stems. >[...] >> And then there's all the diseases that have become >> resistant to the drugs used to treat them. >[...] >> These are all examples of natural selection at work. > >Neither of these is natural selection, in that the selection pressures are >being applied by man. What? Do you really think it makes a difference to dandelions and viruses and bacteria (and insects which develop resistance to insecticides) that the changes in their environment were brought about by humans? As far as they're concerned, we're just another species. We may like to think of ourselves as outside of, or beyond, nature, but we're not, and we'd do well to remember it. If we realized that we have the same ties to the earth and "nature" that all the rest of the species have, maybe we'd be a little more careful about fouling pretty much anything that strikes us as inconvenient. "Human" <==> "beyond nature" is an arrogant, anthropocentric delusion. -- --JB ((Just) Beth Christy, U. of Chicago, ..!ihnp4!gargoyle!sphinx!beth) All we learn from history is that we don't learn anything from history.
falk@sun.uucp (Ed Falk) (12/17/86)
> > I read one author who, noting that many women have given birth without > > ever apparently having had sex, thinks that virgin birth is possible in > > humans. > > This seems very unlikely, because artificial stimulation of a > mammalian egg causes development to occur only up to a certain point > (gastrulation I think), after which it always becomes abnormal, and cannot > proceed further. As far as I know, the reason for this is not known; it works > fine in many other organisms, and even occurs naturally in some (such as some > lizards, which are near the same evolutionary path as mammals, although not as > advanced (mammals evolved from reptiles)). > There is a method called "parthogenesis" in which an egg cell is produced with a full complement of chromosomes (instead of just 23). The resulting child would be a full genetic clone of the mother. Some sci-fi stories have been written that deal with a world where all the men have died off and the women are perpetuating the race this way. Biologists have figured that the odds of this happening spontaneously vary from one in several hundred thousand to one in several hundred million. About two decades ago, the British medical journal "Lancet" conducted a survey to see if such a case could be found. Testing is theoretically easy: just do tissue cultures between mother and daughter and look for signs of rejection. At any rate, they got about fifty responses, most of whom could be weeded out because they had misunderstood the article. But when all the testing was done, they had one mother-daughter pair that could not be told apart genetically. It doesn't *prove* that parthogenesis occurred, but they couldn't find any other explanation. Sorry if the details are hazy, it's been a long time since I read about this. -- -ed falk, sun microsystems terrorist, cryptography, DES, drugs, cipher, secret, decode, NSA, CIA, NRO. (The above is food for the NSA line eater.)