DOI: 10.5061/dryad.rn8pk0pk9
title: The condition-dependence of male genital size and shape

description: The male genitals of internal fertilizers evolve rapidly and divergently,
 and sexual selection is generally responsible for this. Many sexually
 selected traits are condition-dependent - with their expression dependent
 upon the resources available to be allocated to them - as revealed by
 genetic or environmental manipulations of the condition. However, it is
 not clear whether male genitals are also condition-dependent. Here we
 manipulate the condition in two ways (via inbreeding and diet) to test the
 condition-dependence of the genital arch of Drosophila simulans. We found
 that genital size but not genital shape suffered from inbreeding
 depression, whereas genital size and shape were affected by dietary
 manipulation of the condition. The differential effects of these
 treatments likely reflect the underlying genetic architecture that has
 been shaped by past selection: inbreeding depression is only expected when
 traits have a history of directional selection, while diet impacts traits
 regardless of historical selection. Nonetheless, our results suggest
 genitals can be condition-dependent like other sexually selected traits.
description: A <em>Drosophila simulans</em> stock outbred
 population, derived from flies collected in Australia in 2004, was used as
 part of the inbreeding and diet experiments. 
description: # The condition-dependence of male genital size and shape
 [https://doi.org/10.5061/dryad.rn8pk0pk9](https://doi.org/10.5061/dryad.rn8pk0pk9) All data necessary to reproduce findings from the manuscript. ## Description of the data and file structure 1\) Repeatability_Measurements * Repeatability measurements (measurements A and B) for genital Relative Warp (RW) scores for all Relative Warps (RW1-5 explained most variation in shape and was therefore used in the analyses). * Repeatability measurements (measurements A and B) for centroid size. 2\) Diet_Restriction_Data * In column 'DietRestriction', '0' refers to an ad libitum diet, and '40' refers to a restricted diet. * Genital Relative Warp (RW) scores for diet restriction experiment. RW1-5 explained most variation in shape and was therefore used in the analyses. * Centroid sizes (ScaledCentroidSize) for diet restriction experiment. * Leg length (um) for diet restriction experiment. 3\) Inbreeding_Data * 'Cross' refers to inbred or outbred crosses. 'FamilyA' and 'FamilyB' refer to the IDs of families used in the crosses. 'Group' refers to the IDs of groups formed by each pair of families. * Genital Relative Warp (RW) scores for the inbreeding experiment. RW1-5 explained most variation in shape and was therefore used in the analyses * Centroid sizes (ScaledCentroidSize) for inbreeding experiment. * Leg length (um) for the inbreeding experiment. 4\) Group_Means_Inbreeding_Shape * Data for pairwise analysis. 'Group' refers to the IDs of groups formed by each pair of families. * Average genital Relative Warp scores for inbred and outbred individuals from each group. For example, 'AvgOutRW1' refers to the average score of Relative Warp 1 for outbred individuals, and 'AvgInbRW1' refers to the average score of Relative Warp 1 for outbred individuals. * Average centroid sizes for inbred (AvgInbCentSize) and outbred (AvgOutCentSize) individuals from each group. 5\) Diet_and_Total_Offspring * Total offspring count for males on restricted ('dietrestiction'=40) and ad-libitum ('dietrestriction'=0) diet. Columns 's1off', 's2off', and 's3off' refer to offspring counts from the three vials used for fitness assays, and 'totoff' refers to the total offspring counted from the three vials.