Effects of a sex ratio gradient on female mate-copying and choosiness in Drosophila melanogaster

• 来源期刊: 动物学报（英文版）
• 年，卷（期）: 2018,（2）
• 页码范围: 251-258
• 页数: 8页
• 语种: 英文
• DOI: 10.1093/cz/zoy014

摘要

In many sexually reproducing species,individuals can gather information about potential mates by observing their mating success.This behavioral pattern,that we call mate-copying,was reported in the fruit fly Drosophila melanogaster where females choosing between 2 males of contrasting phenotypes can build a preference for males of the phenotype they previously saw being chosen by a demonstrator female.As sex ratio is known to affect mate choice,our goal was to test whether mate-copying is also affected by encountered sex ratios.Thus,we created a gradient of sex ratio during demonstrations of mate-copying experiments by changing the number of females observing from a central arena 6 simultaneous demonstrations unfolding in 6 peripheral compartments of a hexagonal device.We also tested whether the sex ratio experienced by females during demonstrations affected their choosiness (male courtship duration and double courtship rate) in subsequent mate-choice tests.Experimental male:female sex ratio during demonstrations did not affect mate-copying indices,but positively affected the proportion of both males courting the female during mate-choice tests,as well as male courtship duration,the latter potentially explaining the former relationship.As expected,the sex ratio affected female choosiness positively,and Drosophila females seem to have evolved a mate-copying ability independently of sex ratio,and a capacity to adapt their choosiness to male availability.This suggests that,as in many animal species,individuals,especially females,can adapt their mate choice depending on the current sex ratio.