Asymmetry and fitness in female yellow dung flies

Abstract

Fluctuating asymmetry (FA) has been widely used as a measure of developmental stability, and two recent metaanalyses suggest FA may be associated with several fitness components, including fecundity, growth rate and longevity. However, these studies have been strongly criticised on a number of grounds, and it was suggested that further evidence was required before the importance of any associations could be accurately assessed. Furthermore, studies should be of individual FA and fitness components. Here we investigated associations between individual FA of the mid and hind tibia and several fitness related traits (including fecundity, fertility, longevity and offspring development time) in female yellow dung flies (Scathophaga stercoraria). As in several previous studies, asymmetry could be discerned from measurement error and was FA. However, we found no significant associations between any measure of FA and any fitness component regardless of how the data were analysed. Our results therefore do not support any fitness-FA association and suggest that as with other aspects of FA, associations may be trait and species specific. © 2002 The Linnean Society of London.