Inbreeding depression in a sexually selected weapon and the homologue in females

Theory predicts that traits with heightened condition-dependence, such as sexually selected traits, should be affected by inbreeding to a greater degree than other traits. The presence of environmental stress may compound the negative consequences of inbreeding depression. In this study we examined inbreeding depression across multiple traits and whether it increased with a known form of environmental stress. We conducted our experiment using both sexes of the sexually dimorphic leaf-footed cactus bug, Narnia femorata (Hemiptera: Coreidae). Adult male cactus bugs have enlarged hind legs used as weapons in male-male contests; these traits, and their homologue in females, have been previously found to exhibit high condition-dependence. In this study, we employed small developmental group size as an environmental stress challenge. Nymph N. femorata aggregate throughout their juvenile stages, and previous work has shown the negative effects of small group size on survivorship and body size...., Parental generation (Fp): Fifth instar nymphs were collected from the Ordway-Swisher Biological Station (Melrose, FL) in September 2014. Individual nymphs were kept in plastic deli containers, with topsoil, and a cactus pad (Opuntia mesacantha) with ripe fruit attached to it. This rearing protocol works for all life stages in this species (Allen et al., 2018). After nymphs molted into adults and reached sexual maturity (two weeks after molting), we randomly paired males and females.
Parental pairs (Fp): Male-female pairs were allowed to mate freely, and ripe fruit was provided (one per cup). After eggs were laid, we removed them and placed them in a new container with cactus and no fruit (1st instar nymphs do not feed). We selected the first 15 eggs from each of 32 females over a two-week period.
Founding generation nymphs (F0): Once the eggs hatched and nymphs reached the 2nd instar, each female’s nymphs (15) were split equally into three cups. We supplied two ripe fruit per cup. After..., , # Inbreeding depression in a sexually selected weapon and the homologue in females

[https://doi.org/10.5061/dryad.2ngf1vhvw](https://doi.org/10.5061/dryad.2ngf1vhvw)

In this study, we aimed to determine the effects of inbreeding and environmental stress (in the form of reduced group size during development) on traits with heightened condition-dependence versus other morphological traits. For this purpose, we used a true bug (Hemiptera) from the family Coreidae, *Narnia femorata*. As all hemipterans do, this insect has a nymphal juvenile stage in which small instars (tiny versions of adult) hatch out of the egg and then growth through molting processes between instars until they reach the winged adult stage.

The data presented here are the morphological measurements for all the adult insects used in this study, all 560 insects for which we collected all 8 morphological measurements, all measurements are in **millimeters**.

The experimental treatments represent the environment that th...