Sex Chromosomes and Sexual Selection in Poeciliid Fishes

Abstract

We propose that the evolution of female preferences can be strongly influenced by linkage of attractive male traits to the Y chromosome and female preferences to the X chromosome in male heterogametic species. Such linkage patterns are predicted by models of the evolution of sexually antagonistic genes. Subsequent recombination of attractive male characters from the Y to the X would create physical linkage between attractive male trait and preference. A literature survey shows that Y linkage of potentially sexually antagonistic traits is common in poeciliid fishes and other species with sex chromosomes that are not well differentiated, but may also occur in taxa with degenerate Y chromosomes. In the guppy, attractive male traits are primarily Y and X linked; a literature review of the inheritance of sex-limited attractive male characters suggests that 16 are Y linked, 24 recombine between the X and Y, two are X linked, and two are autosomal. Crosses and backcrosses between high female preference (Endler's live-bearers) and low female preference (Rio San Miguel) guppy populations show that this character has a strong additive genetic component and that it will be possible to investigate the physical linkage of male and female sexually selected characters in this species through mapping studies.

Variations on a theme: Genomics of sex determination in the cichlid fish Astatotilapia burtoni

“…This repeated usage of descendants of TEL3 as a sex chromosome could be linked to the presence of sexually antagonistic genes on TEL3. On fish sex chromosomes, sexually antagonistic genes are often involved in pigmentation (table 2 in [83]). The homologs of TEL3 carry several pigmentation genes as well as some of the color vision opsin genes ([38], table 2 in [66]), making this chromosome one of the “limited options” that could evolutionarily be favored as sex chromosome due to location of sexually antagonistic loci on it and their linkage to SD genes.…”

Sexual Behavior, Genes, and Evolution inXiphophorus

“…Since males are the heterogametic sex in swordtails, these genes should accumulate on the Y chromosome, [18][19][20] which in turn favors a reduction in recombination between the sex chromosomes. A recent review 21 suggests that this is the case particularly in taxa like Xiphophorus, where males have a nondegenerate heterogametic sex chromosome.…”

An XX/XY heteromorphic sex chromosome system in the Australian chelid turtle Emydura macquarii: A new piece in the puzzle of sex chromosome evolution in turtles

“…Consequently, the evolution of sex chromosomes has significant consequences for the evolution of sex ratio, sexual dimorphism, sexual selection, sexual conflict, and ultimately, speciation and extinction (e.g. Berry & Shine 1980, Rice 1984, Lindholm & Breden 2002, Edwards et al 2005, Saether et al 2007. Therefore, it is critical to correctly identify sex chromosome systems if we are to understand their evolution and the evolution of these related traits.…”