Sex chromosomes and male ornaments: a comparative evaluation in ray-finned fishes.
Theory predicts that the mechanism of genetic sex determination can substantially influence the evolution of sexually selected traits. For example, female heterogamety (ZZ/ZW) can favour the evolution of extreme male traits under Fisher's runaway model of sexual selection. We empirically test whether the genetic system of sex determination has played a role in the evolution of exaggerated male ornaments in actinopterygiian fishes, a clade in which both female-heterogametic and male-heterogametic systems of sex determination have evolved multiple times. Using comparative methods both uncorrected and corrected for phylogenetic non-independence, we detected no significant correlation between sex-chromosome systems and sexually selected traits in males. Results suggest that sex-determination mechanism is at best a relatively minor factor affecting the outcomes of sexual selection in ray-finned fishes.
Department of Genetics, Life Sciences Building, University of Georgia, Athens, GA 30602, USA. jemank@uga.edu
Judith E
JE
Mank
David W
DW
Hall
Mark
M
Kirkpatrick
John C
JC
Avise
D000818:Animals; D005075:Biological Evolution; D005260:Female; D005399:Fishes / Q000033:anatomy & histology* / Q000235:genetics*; D008297:Male; D010641:Phenotype; D012727:Sex Characteristics; D012730:Sex Chromosomes / Q000235:genetics*