hes@ecsvax.UUCP (Henry Schaffer) (01/31/88)
In article <1651@brahma.cs.hw.ac.uk>, jack@cs.hw.ac.uk (Jack Campin) writes: > Most creationists love to say that nobody has ever observed a new species > being created. I know this is wrong but I couldn't actually cite a specific > counterexample. Bacteria must be easy; I vaguely remember reading about > a new species of mosquito. I suppose something warm and fluffy might be too > much to ask for, but can someone post some examples of observed speciation > in reasonably complex life forms? > -- > ARPA: jack%cs.glasgow.ac.uk@nss.cs.ucl.ac.uk > JANET:jack@uk.ac.glasgow.cs USENET: ...mcvax!ukc!cs.glasgow.ac.uk!jack > Mail: Jack Campin, Computing Science Department, University of Glasgow, > 17 Lilybank Gardens, Glasgow G12 8QQ, Scotland (041 339 8855 x 6045) Look it up in a genetics or botany text. (I discussed it at length a couple of years ago - I'll look to see if I still have something on it.) Briefly - in an attempt to get a plant which had raddish root and a cabbage head, the two were crossed (genera are Raphanus and Brassica) - after the chromosomes of the (sterile) hybrid were doubled - there was a self-fertile plant which could not breed with either the raddish or cabbage parental species. Does this count? --henry schaffer n c state univ P.S. It doesn't pay to fool around with Mother Nature - Raphanobrassica has a cabbage root and a raddish top!
ajw@manatee.cis.ufl.edu (Andy Wilcox) (02/05/88)
I recently heard of a new kind of cat, the 'King Cheetah' that has been observed wherever they live (African plains, I guess). It is a very beautiful animal, similiar to the cheetah but with large ovals replacing the spots. If you've ever seen a butterfly tabby domestic cat you know what I mean. Does this qualify as a new species? In addition, there was some kind of moth in England that changed color with the industrial revolution to match the color of the (now blackened) tree trunks. This was due to the birds eating the light colored moths. There was no guess as to why the king cheetah occured. If this show ever comes around on Discovery again, I'll pay closer attention. --Andy Wilcox (ajw@manatee.cis.ufl.edu)
gagen@bgsuvax.UUCP (kathleen gagen) (02/06/88)
From article <10628@uflorida.cis.ufl.EDU>, by ajw@manatee.cis.ufl.edu (Andy Wilcox): > > In addition, there was some kind of moth in England that changed color > with the industrial revolution to match the color of the (now > blackened) tree trunks. This was due to the birds eating the light > colored moths. This is not an example of speciation. It is my understanding that the original moths included mostly light colored moths with an occassional rare dark moth. Befor the industrial revolution, the light colored moths had a selective advantage due to protective coloration. The advant of the industrial revolution was accompanied by a change in the environment. Industrial soot turned the environment black. As a result, the few rare dark moths blended in with their environment while the light moths were more easily seen by the birds looking for dinner. As a result, a progressively larger proportion of dark moths survived and reproduced while a progressively larger proportion of light colored moths were eaten. Gobbled moths leave few progeny. As a result, there was an increase in the frequency of genes coding for dark coloration. This progressive shift in gene frequency over several generations resulted in dark coloration becomming the dominant phenotype. A review of this phenomemon can be obtained from any good evolutionary genetics test. ---- Kathi Gagen -- Kathleen Pausic Gagen ...!cbosgd!osu-cis!bgsuvax!gagen Dept. of Biological Sciences gagen@research1.bgsu.edu Bowling Green State University gagen%bgsu.csnet@csnet-relay.arpa Bowling Green Ohio 43403 gagen%andy.bgsu.edu@csnet-relay.csnet