The effects of sexual selection on the foraging behaviour of the Gulf coast fiddler crab, Uca panacea.




Caravello, H.E.
Cameron, G.N.

Journal Title

Journal ISSN

Volume Title



Sexual selection has resulted in sexually dimorphic appendages in the Gulf Coast fiddler crab. Male crabs possess one enlarged major claw used for mate attraction and one normal-sized feeding claw, while females possess two functional feeding claws. The hypothesis that males modify their foraging relative to females to reduce the 'cost' of this non-functional feeding appendage was tested. Behavioural (increased foraging time or rate, priority of access to areas of higher organic (food) content) and morphological (greater efficiency of extracting or processing food material) mechanisms were investigated. Increased foraging rates coupled with a larger functional feeding claw allowed male U. panacea to maintain an energy intake equivalent to that of females. Natural selection has produced behavioural and morphological mechanisms that restore the loss of foraging ability caused by sexual selection for increased major claw size.


p. 1864-1874


natural selection, fiddler crab, crabs, feeding behavior, Uca panacea, sexual dimorphism, animal morphology, feeding