Developmental order of a secondary sexual trait reflects gonadal development in male sheepshead minnows (Cyprinodon variegatus)

作者：Lee Who Seung^*; Mangel Marc; Munch Stephan B

来源：Evolutionary Ecology Research, 2017, 18(5): 531-538.

• development
• gonads
• secondary sexual trait
• sexual colour

Question: How can one demonstrate that coloration is an honest signal of sexual development?
Hypothesis: Coloration in a cyprinid fish is positively related to the development of testes.
Species and location: Sheepshead minnows (Cyprinodon variegatus) from South Carolina and Connecticut moved to Santa Cruz, California.
Methods: Common garden experiment involving individually grown fish, colour pattern assessment, and the development of male gonads.
Results: Males developed bright iridescent blue coloration on their upper parts in front of the dorsal fin through four stages that were positively related to the growth of testes. Such parallel development between sexual coloration and gonad mass was consistent between populations.
Conclusions: Coloration in male sheepshead minnows provides an accurate signal of the maturity status of males, which can thus inform both mate choice and intrasexual competition.

• 出版日期2017-9