ahouse@BINAH.CC.BRANDEIS.EDU (Jeremy Ahouse) (03/08/91)
Evolution and maintenance of "sex" discussions always leave me wondering: How much can be explained by these traits being derived characters? Certainly in vertebrates that seems reasonable. With all of the "machinery" in place that vertebrates have it seems likely that all of the Maynard-Smith cost benefit analysis is not really the right kind of explanation here. The fish examples that break out of the cycle still have stereotyped behaviours in place and some even mate with other species -- the pull of ancestral character states... I think you really have to focus on those organisms where examples of different "solutions" are possible isogamy:anisogamy/monoecious:diecious. So plants are the perfect place to look for origination and maintenance of these "strategies." And still it is vital that the artifacts of derived characters be dealt with. If a taxon has many representatives their number is not necessarily linked or caused by the method of reproduction. So now, what if I suggest that reproductive method is all ancestral... will that bring a hailstorm of rebuttals? Jeremy Ahouse Brandeis Univeristy Biophysics program
zlraa@marlin.jcu.edu.au (Ross Alford) (03/09/91)
In article <00945449.40578380@BINAH.CC.BRANDEIS.EDU> ahouse@BINAH.CC.BRANDEIS.EDU (Jeremy Ahouse) writes: >Evolution and maintenance of "sex" discussions always leave me wondering: How >much can be explained by these traits being derived characters? ... >I think you really have to focus on those organisms where examples of different >"solutions" are possible isogamy:anisogamy/monoecious:diecious. So plants are >the perfect place to look for origination and maintenance of these >"strategies." And still it is vital that the artifacts of derived characters >be dealt with. If a taxon has many representatives their number is not >necessarily linked or caused by the method of reproduction. > >So now, what if I suggest that reproductive method is all ancestral... will >that bring a hailstorm of rebuttals? > I basically agree with your points; indeed I think your opinions are largely coincident with mine. I certainly think that the most interesting organisms to look at for experimental/observational data on the evolution of either anisogamy or dioecy would be groups which exhibit more than one mode, so that there is some chance of distinguishing history from ongoing selection. As for a hailstorm of rebuttals...Your article is the first posting I've seen in response to my original one. Perhaps one small cocktail ice cube of rebuttal is more likely? Ross Alford -- Ross A. Alford Department of Zoology Internet: zlraa@marlin.jcu.edu.au James Cook University Phone: +61 77 81 4732 Townsville, Qld 4811 Australia