Sexual shape dimorphism accelerated by male-male competition, but not prevented by sex-indiscriminate parental care in dung beetles (Scarabaeidae).

ABSTRACT: Dimorphic sexual differences in shape and body size are called sexual dimorphism and sexual size dimorphism, respectively. The degrees of both dimorphisms are considered to increase with sexual selection, represented by male-male competition. However, the degrees of the two dimorphisms often differ within a species. In some dung beetles, typical sexual shape dimorphisms are seen in male horns and other exaggerated traits, although sexual size dimorphism looks rare. We hypothesized that the evolution of this sexual shape dimorphism without sexual size dimorphism is caused by male-male competition and their crucial and sex-indiscriminate provisioning behaviors, in which parents provide the equivalent size of brood ball with each of both sons and daughters indiscriminately. As a result of ind

SUBMITTER: Kishi S 

PROVIDER: S-EPMC4541983 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature