Inter-individual variation in the diet within a group of Japanese macaques and its relationship with social structure investigated by stable isotope and DNA analyses.

We investigated individual variation in diet in relation to age-sex class and kin relationship in 28 of 40 members of a small group of wild Japanese macaques (Macaca fuscata). We used stable isotope ratios from hair as an index of individual dietary profiles, genetic relatedness as an index of kin relationship, and mitochondrial DNA (mtDNA) haplotype as a marker of being an immigrant or native member of the group. The range of carbon and nitrogen stable isotope ratios from hair of individual macaques (δC: -24.

Seasonal and sexual variation in the diet and gastrointestinal features of the sika deer in western Japan: implications for the feeding strategy.

Sexual and seasonal variation in diet quality and the gastrointestine have important implications for forage acquisition and the feeding strategy. We assessed the botanical and chemical compositions of the diet and the gastrointestinal macrostructure of the sika deer (Cervus nippon) in western Japan. The sexual dimorphism-body size hypothesis predicts that smaller females will have a better diet than larger males to meet a higher nutritional demand due to a higher metabolic rate.

Sexual variations in food quality and gastrointestinal features of sika deer (Cervus nippon) in Japan during winter: implications for feeding strategy.

We assessed sexual variation in food quality and gut macrostructure in adult male and pregnant female sika deer, Cervus nippon (Temminck, 1838), in Japan during winter. These variations might have important implications relative to sexual differences in habitat use, forage acquisition, and digestive strategy. According to the sexual dimorphism-body size hypothesis the larger males would feed on poorer forage and have heavier stomach contents and heavier intestine contents and longer intestines than smaller females.