Animal coloration has a wide range of biological functions and may be subject to different,sometimes conficting,selective pressures.In crustaceans,the evolution of coloration is relatively unstudied,despite the broad ...Animal coloration has a wide range of biological functions and may be subject to different,sometimes conficting,selective pressures.In crustaceans,the evolution of coloration is relatively unstudied,despite the broad range of colors and color patterns,which includes variability at multiple levels.Freshwater crayfsh are known to show color variability within species and populations,as well as intra-individual variability,but thefunction,if any,of crayfsh coloration is largely unknown.Here,I report on an experiment to understand patterns of color variability in the crayfsh Faxonius virilis and show that variation is strongly correlated to ontogenetic changes from a summer non-reproductive form to a fall reproductiveform.Crayfsh showed comparatively little inter-and intra-individual color variation in their non-reproductive form,but substantial variation at bothlevels in the reproductive form.Transition to the reproductive form was associated with the development of greener or bluer coloration localizedto the chelae on a subset of individuals,but these changes showed no clear correlation with sex or body size.Future investigations should focuson determining whether differences in color between individuals in the mating season are associated with any physiological or behavioral differences,or with differential susceptibility to predation.展开更多
文摘Animal coloration has a wide range of biological functions and may be subject to different,sometimes conficting,selective pressures.In crustaceans,the evolution of coloration is relatively unstudied,despite the broad range of colors and color patterns,which includes variability at multiple levels.Freshwater crayfsh are known to show color variability within species and populations,as well as intra-individual variability,but thefunction,if any,of crayfsh coloration is largely unknown.Here,I report on an experiment to understand patterns of color variability in the crayfsh Faxonius virilis and show that variation is strongly correlated to ontogenetic changes from a summer non-reproductive form to a fall reproductiveform.Crayfsh showed comparatively little inter-and intra-individual color variation in their non-reproductive form,but substantial variation at bothlevels in the reproductive form.Transition to the reproductive form was associated with the development of greener or bluer coloration localizedto the chelae on a subset of individuals,but these changes showed no clear correlation with sex or body size.Future investigations should focuson determining whether differences in color between individuals in the mating season are associated with any physiological or behavioral differences,or with differential susceptibility to predation.
