DOI: 10.5061/dryad.7dd43
title: Data from: The complexity of mating decisions in stalk-eyed flies

description: All too often, studies of sexual selection focus exclusively on the
 responses in one sex, on single traits, typically those that are
 exaggerated and strongly sexually dimorphic. They ignore a range of less
 obvious traits and behavior, in both sexes, involved in the interactions
 leading to mate choice. To remedy this imbalance, we analyze a textbook
 example of sexual selection in the stalk-eyed fly (Diasemopsis meigenii).
 We studied several traits in a novel, insightful, and efficient
 experimental design, examining 2,400 male–female pairs in a “round-robin”
 array, where each female was tested against multiple males and vice versa.
 In D. meigenii, females exhibit strong mate preference for males with
 highly exaggerated eyespan, and so we deliberately constrained variation
 in male eyespan to reveal the importance of other traits. Males performing
 more precopulatory behavior were more likely to attempt to mate with
 females and be accepted by them. However, behavior was not a necessary
 part of courtship, as it was absent from over almost half the
 interactions. Males with larger reproductive organs (testes and accessory
 glands) did not make more mating attempts, but there was a strong tendency
 for females to accept mating attempts from such males. How females detect
 differences in male reproductive organ size remains unclear. In addition,
 females with larger eyespan, an indicator of size and fecundity, attracted
 more mating attempts from males, but this trait did not alter female
 acceptance. Genetic variation among males had a strong influence on male
 mating attempts and female acceptance, both via the traits we studied and
 other unmeasured attributes. These findings demonstrate the importance of
 assaying multiple traits in males and females, rather than focusing solely
 on prominent and exaggerated sexually dimorphic traits. The approach
 allows a more complete understanding of the complex mating decisions made
 by both males and females.
description: 2400 male-female mating
 pairs outcomesMales&Females.xlsx
 This file contains all information of each male-female pair, along with
 PCA for reproductive organs and behavior. The columns are labelled: Line –
 inbred line (12) in.out – inbred/outbred status (outbred all belong to one
 line) Male.ES – male eyespan Male.Thorax Testes AG – Accessory Glands
 Female.ID Female.ES – female eyespan Accept.Reject – given that a mating
 attempt occurred Male.ID Attempt – was there a mating attempt, yes or no
 Follow – a behaviour Bob – a behavior Grapple – a behavior Time.to.mate –
 how many seconds untila mating attempt Date – block structure Time.in.pair
 – same as Time.to.mate except that those where there was no mating attempt
 are labelled 900 seconds PC.Reporgan – PCA Testes and Accessory Glands
 PC1Beh.min – PCA of three behaviours per minute PC2Beh.min - PCA of three
 behaviours per minuteMales&Females.xlsxMaleSummaryThis file is an abstraction from the larger file Males&Females.xlsx, summarizing for each male. Behaviour is not recorded here as it relates to the particular pair.