title: Sex-specific fitness effects of nutrient intake on reproduction and lifespan.
abstract: Diet affects both lifespan and reproduction [1-9], leading to the prediction that the contrasting reproductive strategies of the sexes should result in sex-specific effects of nutrition on fitness and longevity [6, 10] and favor different patterns of nutrient intake in males and females. However, males and females share most of their genome and intralocus sexual conflict may prevent sex-specific diet optimization. We show that both male and female longevity were maximized on a high-carbohydrate low-protein diet in field crickets Teleogryllus commodus, but male and female lifetime reproductive performances were maximized in markedly different parts of the nutrient intake landscape. Given a choice, crickets exhibited sex-specific dietary preference in the direction that increases reproductive performance, but this sexual dimorphism in preference was incomplete, with both sexes displaced from the optimum diet for lifetime reproduction. Sexes are, therefore, constrained in their ability to reach their sex-specific dietary optima by the shared biology of diet choice. Our data suggest that sex-specific selection has thus far failed fully to resolve intralocus sexual conflict over diet optimization. Such conflict may be an important factor linking nutrition and reproduction to lifespan and aging.
authors.affiliation: Evolution & Ecology Research Centre and School of Biological, Earth and Environmental Sciences, The University of New South Wales, Kensington, Sydney 2052, Australia. a.maklakov@unsw.edu.au
authors.forename: Alexei A
authors.initials: AA
authors.lastname: Maklakov
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Simpson
authors.forename: Felix
authors.initials: F
authors.lastname: Zajitschek
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Hall
authors.forename: Josephine
authors.initials: J
authors.lastname: Dessmann
authors.forename: Fiona
authors.initials: F
authors.lastname: Clissold
authors.forename: David
authors.initials: D
authors.lastname: Raubenheimer
authors.forename: Russell
authors.initials: R
authors.lastname: Bonduriansky
authors.forename: Robert C
authors.initials: RC
authors.lastname: Brooks
mesh_terms: D000818:Animals; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D004435:Eating; D005260:Female; D005502:Food; D005518:Food Preferences; D006135:Gryllidae / Q000502:physiology; D008136:Longevity / Q000502:physiology*; D008297:Male; D012098:Reproduction / Q000502:physiology*; D012727:Sex Characteristics
chemical_list: D004040:Dietary Carbohydrates; D004044:Dietary Proteins