Aging modulates cuticular hydrocarbons and sexual attractiveness inDrosophila melanogaster

Abstract

SUMMARY Attractiveness is a major component of sexual selection that is dependent on sexual characteristics, such as pheromone production, which often reflect an individual’s fitness and reproductive potential. Aging is a process that results in a steady decline in survival and reproductive output, yet little is known about its effect on specific aspects of attractiveness. In this report we asked how aging impacts pheromone production and sexual attractiveness in Drosophila melanogaster. Evidence suggests that key pheromones in Drosophila are produced as cuticular hydrocarbons (CHC), whose functions in attracting mates and influencing behavior have been widely studied. We employed gas chromatography/mass spectrometry and laser desorption/ionization mass spectrometry to show that the composition of D. melanogaster CHC is significantly affected by aging in both sexes and that these changes are robust to different genetic backgrounds. Aging affected the relative levels of many individual CHC, and it shifted overall hydrocarbon profiles to favor compounds with longer chain lengths. We also show that the observed aging-related changes in CHC profiles are responsible for a significant reduction in sexual attractiveness. These studies illuminate causal links among pheromones, aging and attractiveness and suggest that CHC production may be an honest indicator of animal health and fertility.

Deciphering the signature of cuticular lipids with contact sex pheromone function in a parasitic wasp

“…A change in the CHC profiles during ageing and a decreasing sexual attractiveness was recently also reported in Drosophila melanogaster (Kuo et al, 2012). As previously shown in our studies on L. distinguendus (Steiner et al, 2005;Steiner et al, 2007), the authors found a shift towards compounds with longer chain-lengths and observed a correlation with decreasing sexual attractiveness.…”

The song of the old mother: Reproductive senescence in female drosophila

“…45 For example, CHC profiles changed in consistent ways most notably by producing higher proportions of long-chain compounds with increasing age in females from 2 different fly strains. 39 A young female CHC profile was both necessary and sufficient for males to discriminate between chronologically young and old females; male courtship preferences for young vs. old females corresponded with the female CHC profiles, disappeared when CHCs were removed from young and old females by hexane washing, and could be re-directed toward older females when coated in CHCs from younger females (8 d pe vs 52 d pe; 39 ). Female receptivity peaks at >90% 1-2 d pe, then begins to decline approximately 7 d pe in virgin females 27,35,37 and as early as 5 d pe in previously-mated females.…”

“…38 While male courtship vigor toward active (intact) females has not been observed to change with increasing female age (5 d-20 d post-eclosion, hereafter abbreviated as d pe; 37 ), male discrimination based on female age is detected under conditions where some female stimuli are isolated. When females are immobilized and decapitated to prevent rejection responses, males spend »50% less time courting old females than young females (female ages 20 d-1 d pe, 36 ; 52 d vs 8 d pe, 39 ). However, female movement is an important visual signal for mate recognition and courtship initiation.…”

Age and aggregation trigger mating behaviour in the small hive beetle, Aethina tumida (Nitidulidae)

“…An age-dependent response to a sexual pheromone is common in many arthropods (e.g. Klein et al 2012) and can be caused by a variety of factors like age-related variation in the pheromone emission and composition (Coppee et al 2011;Kuo et al 2012;Wang et al 2015) or hormone-triggered behavioural plasticity (Duportets et al 2013;Jarriault et al 2009). Mating of A. tumida follows a fixed order of behaviours which is often interrupted by aggressive females.…”