Loss of sexual signals should be strongly selected against when these signals are necessary for mate attraction or acquisition. Male Teleogryllus oceanicus field crickets produce a long-distance calling song to attract females. Separate genetic mutations recently evolved on the Hawaiian Islands of Kauai and Oahu, rendering approximately 90% and 50% of males, respectively, incapable of calling. We examined whether males from three populations, each with a distinct prevalence of this silent 'flatwing' phenotype, show behavioural plasticity in response to being reared in a call-less environment. Crickets from Kauai, Oahu and Mangaia, a Cook Islands population without the flatwing phenotype, either were or were not exposed to calling song during late juvenile and early adult development. Movement assays showed that when males originating from Kauai were reared in silence, they moved sooner, moved more and spent more time walking during silent behaviour trials than did their counterparts reared with calling song. Males from Oahu and Mangaia, however, showed no such effect of acoustic rearing environment on these behaviours. This suggests that there has been directional selection on Kauai for males to respond to a silent environment by increasing their mobility, thus compensating for their lack of song and increasing their chance of encountering receptive females.
Bibliographical noteFunding Information:
Thanks to E. Bastiaans and E. Maring for assistance with behavioural assays, J. M. Beaty for building the arena, H. Kunerth, L. Lara, E. Maring, E. Schmidtman and J. Walker for assistance in rearing crickets and two anonymous referees for helpful comments on the manuscript. This work was supported by the University of Minnesota and a National Science Foundation grant to M.Z. ( IOS 1261575 ).
© 2015 The Association for the Study of Animal Behaviour.
Copyright 2015 Elsevier B.V., All rights reserved.
- Behavioural plasticity
- Sexual selection
- Signal loss
- Teleogryllus oceanicus