What is Salty's 'semi-meiotic hypothesis'

Hi Salty,The last thread on this subject got closed off before you replied, assuming you were so inclined to my post, please forgive the C+P."Dear Salty,In your essay on Ontogeny and Phylogeny you mention the lack of swim bladders in Darters and state that a Darwinian interpretation insists on a gradual loss of the bladder. This is not true for a neo darwinian interpretation however. Developmental genetics shows that only a very few mutations may be sufficient to cause the loss of a specific organ with no gradual transition required. A recent paper in Nature showed evidence that Stick insects have lost and regained wings several times in the course of their evolution. Has there been any genetic work done to look for genes related to swim bladder development in Darters?MICHAEL F. WHITING, SVEN BRADLER & TAYLOR MAXWELL
Loss and recovery of wings in stick insects
Nature 421, 264 - 267 (2003)"TTFN,Wounded

Sexual reproduction is not thought to get rid of deleterious mutations, that is the role put forward for natural selection. In a permissive enough environment with low selective pressure, which you have pointed out modern medicine provides to some extent, deleterious mutations are free to accumulate.[This message has been edited by Wounded King, 04-23-2003]

It seems a bit much to ask for direct observation of a speciation event driven by sexual selection, which appears to be the only evidence which will satisfy you, does it have to be naturally occurring or would a laboratory experiment showing reproductive isolation by artificial selection be sufficient? There is however a considerable body of theoretical work on the role of sexual isolation on sympatric speciat, one of the clearest examples where sexual reproduction plays a role in 'macroevolution',assuming that by that you mean speciation. There have been numerous studies on a variety of factors, such as mating song preference and hybrid lethal metabolic genes in Drosophila. There are other highly sympartic speciated populations, such as the Lake victoria cichlids and other cichlid lake populations, which provide excellent material for phylogenetic analysis. The following references are purely included as supporting material Lande R, Seehausen O, van Alphen JJ.
Mechanisms of rapid sympatric speciation by sex reversal and sexual selection in cichlid fish.
Genetica. 2001;112-113:435-43.Rice WR.
Experimental tests of the adaptive significance of sexual recombination.
Nat Rev Genet. 2002 Apr;3(4):241-51Van Doorn GS, Luttikhuizen PC, Weissing FJ.
Sexual selection at the protein level drives the extraordinary divergence of sex-related genes during sympatric speciation.
Proc R Soc Lond B Biol Sci. 2001 Oct 22;268(1481):2155-61.Is this paper relevant to your semi-meiotis hypothesis?Pardo-Manuel de Villena F, Sapienza C.
Female meiosis drives karyotypic evolution in mammals.
Genetics. 2001 Nov;159(3):1179-89.(I retrospectively realised that this post breaches the etiquette for this board, so I have beefed it up a bit)[This message has been edited by Wounded King, 04-24-2003][This message has been edited by Wounded King, 04-24-2003]