Because the camers have only one X chromosome, the simpler inheritance can enable genetic changes from certain properties through sexual selection faster
In contrast to natural selection, the sexual selection umbes, so this has already noticed Charles Darwin, a change of change, especially on the men who "Dance" Present in front of the females. As with the peacock whose magnificent tail also characteristics in the intersexal competition, which actually have no direct survival value. While pfauenmannchen impress with their magnificent and striking feather ornaments, the females are rather unnecessary and seem to unsuccess the sexual selection with regard to their appearance and behavior.
Evolutionary biologists from the Genetic Institute of the University of Florida ame that, independently of the nature and shape of sexual selection, men seem more likely to compete together in order to score with the deposition of certain characteristics in the females and to excite their false attention. Although this evolutionary attention concomity had described Darwin for the first time as sexual selection, but did not know genetic mechanisms that allow this environmental prere that emanates from sexual selection relatively quickly in the manifolds in the form of certain changes.
This seems to be the case at least in fruit flying, which like the suction animals and therefore the people have the same chromosomal gender system. The men, so Marta Wayne, Senior Author of the Study Simpler Fashion of Inheritance of Transcriptional Variation in Male Drosophila Melanogaster appeared in the Proceedings of the National Academy of Sciences (PNAs) are simply genetic easier: "The inheritance of men is based on a simpler genetic architecture, which does not require so many interactions between genes, as this could be the case with female inheritance."
The scientists have investigated how the gene expression differs in men and females of the fruit fly. The flies were genetically identical except for the sex chromosomes. As you know, the females have two X chromosomes, which is why the existing genes occur twice, the hemozygous men have an X- and a smaller Y chromosome, so that the genes in the X chromosome exist only once.
That has followed for the inheritance, since in females mutations in genes can be compensated by the second gene, during the man’s mutations by adding. As a result, men can be coded by the genes on the X-chromosome (these are about 4 percent of all genes), rapidly or. Are you subjected to the selection faster than the females. The result is u.a., that with the sex chromosome X is a crossproportion of high number of monogenic arbraits. On the other hand, this is the reason why the teams are stronger of sexual selection and can be carried out accordingly quickly in some properties evolutionar to the females "to win" and to achieve more offspring. The inheritance of the alleles in the men in the X chromosomes designate the scientists as "easier", because they only be given by the nuts and about the daughter.
However, the sexual trial has further effects. Although men and females of the fruit fly have largely the same genes, expression is different in the case of half, sex-specific splashes can occur at 25 percent. In the a total of 9312 genes examined by scientists, only 8 percent were coded sex-specific. 8th.607 genes that were identical in men and females were 7.617 expressed differently in females and men. From 8640 genes that occur in both sexes, genetic variations found themselves in both sexes only at 889, in the remaining, the genetic variation is again sex-specific. "The agreement between the sexes", Write the scientists, "So is quite low." For example, why women and men show different symptoms in diseases: "When it comes to make females and man’s flying, everything revolves around the turning on either in different places or in different mabe or at different times, because we have all the same genes all the same genes."