Natural selection v.s Sexual selection

Natural selection and sexual selection is a selection process in which favorable traits in an individual are favored, by either nature or members of the opposite sex. Natural selection as Darwin explains is the survival of the fittest, on the other hand Dawkins describes this concept as the survival of the stable. Darwin describes natural selection as a process that filters out the weak at any age and allows on the strongest, with the best traits to survive. Sexual selection, Darwin elaborates, is a process at which the mates get to choose the favorable traits even if it is not favorably naturally. For example the huge, long, elaborate tails on the peacock, things that can not be describe though the process of natural selection.

Sex ratio- ESS

Fisher stated that sex ratio of 50:50 is an ESS, because if one looks at it, it holds a strong truth. The 50:50 sex ratio can be for the most part proven, because if you think about it no matter how the initial birth ration is cut it is still going to go back to the 50:50 sex ratio. Lets say for example more males then females were born this year that would mean that females had a bigger advantage when it came to finding a mate and that some of the males were not going to be able to mate, and die off. Even if you look at it the other way around in which there were more females than males then some of the female would go unmated and end up dying off, and this would still drive the sex ratio back to 50:50. Autosomes would favor this because autosomes are only carry half of the genes and when two of different sexes combine then it makes up the diploid. On the other hand sex chromosomes would not favor this because they want to be favored over the other. Sex chromosomes think that the next generation should only be made up of their genes.