International Journal of Evolutionary Biology / 2012 / Article / Fig 2

Review Article

Why Chromosome Palindromes?

Figure 2

(a) The three processes that lead to degeneration of the Y chromosome: Muller's ratchet (see [109] for details of how every turn of the ratchet is followed by fixation of a deleterious allele), background selection, and genetic hitchhiking. Only in the case of genetic hitchhiking, the fitness of the Y chromosome increases through time.