rh@smds.UUCP (Richard Harter) (08/07/90)
"... The same has been demonstrated by the genetic revolution in the founder population of Drosophila pseudoobscura at Bogota. This population is still remarkably similiar to the Central and North American populations of the species and no behavioral isolation of either males or females of the Bogota population from North American flies was found. Yet, F1 males obtained from the cross of D. pseudo- obscura females from Bogota with males of this species from the North American mainland (from Guatemala north) are sterile. This sterility is due to about two genes located on the X chromosome and one each on two of the other chromosomes...", Mayr. This particular observation struck me for the following reason. One of the precipitating events for speciation is reproductive isolation. This can happen in a number of ways, of course, but the cited mechanism is particularly quick and effacious. The interesting thing is that the selection occurs in the second generation in the males only. I would take this as a particularly clear example of the power of sexual reproduction to facilitate speciation. Note: this has been posted to multiple groups. Please select the appropriate group for followups. -- Richard Harter, Software Maintenance and Development Systems, Inc. Net address: jjmhome!smds!rh Phone: 508-369-7398 US Mail: SMDS Inc., PO Box 555, Concord MA 01742 This sentence no verb. This sentence short. This signature done.