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Abstract Behavioural plasticity is a major driver in the early stages of adaptation, but its effects in mediating evolution remain elusive because behavioural plasticity itself can evolve.In this study, we investigated how male Trinidadian guppies (Poecilia reticulata) adapted to different predation regimes diverged in behavioural plasticity of their mating tactic. We reared F2 juveniles of high‐ or low‐predation population origins with different combinations of social and predator cues and assayed their mating behaviour upon sexual maturity.High‐predation males learned their mating tactic from conspecific adults as juveniles, while low‐predation males did not. High‐predation males increased courtship when exposed to chemical predator cues during development; low‐predation males decreased courtship in response to immediate chemical predator cues, but only when they were not exposed to such cues during development.Behavioural changes induced by predator cues were associated with developmental plasticity in brain morphology, but changes acquired through social learning were not.We thus show that guppy populations diverged in their response to social and ecological cues during development, and correlational evidence suggests that different cues can shape the same behaviour via different neural mechanisms. Our study demonstrates that behavioural plasticity, both environmentally induced and socially learnt, evolves rapidly and shapes adaptation when organisms colonize ecologically divergent habitats.
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The direction and strength of social plasticity in mating signals and mate preferences vary with the life stage of induction
Socially induced plasticity in mating signals and mate preferences is widespread in animals. The timing of plasticity induction is key for mating and evolutionary consequences: plasticity induced before and after dispersal often results in different patterns of mate choices. Here we discuss two additional factors that may be of importance: the nature of social interactions that are involved at different stages, and the direction and strength of the effects. We review a case study with the Enchenopa binotata species complex of treehoppers. In spite of a wide scope for social plasticity in E. binotata across life stages, effects of the juvenile social environment were stronger and more common, especially those influencing the signalepreference relationship. These results emphasize the importance of studying variation in plasticity induced along various life stages and of considering all the mating traits that may be socially plastic. We suggest that systematic investigation of these patterns across taxa will help better understand the origin of diversity in animal communication systems.
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- Award ID(s):
- 1855962
- PAR ID:
- 10507566
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Animal Behaviour
- Volume:
- 200
- Issue:
- C
- ISSN:
- 0003-3472
- Page Range / eLocation ID:
- 255 to 261
- Subject(s) / Keyword(s):
- behavioural plasticity, life stage, mating signal evolution, preference function, signal ontogeny
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1016/j.anbehav.2023.03.008
