Sherratt, T.N. and Franks, D.W. (2005) Do unprofitable prey evolve traits that profitable prey find difficult to exploit? Proceedings of the Royal Society Series B, 272 (1579). pp. 2441-2447. ISSN 0962-8452
Prey that are unprofitable to attack (for example, those containing noxious chemicals) are often conspicuously patterned and move in a slower and more predictable manner than species lacking these defences. Contemporary theories suggest these traits have evolved as warning signals because they can facilitate both associative and discriminative avoidance learning in predators. However, it is unclear why these particular traits and not others have tended to evolve in unprofitable prey. Here we show using a signal detection model that unprofitable prey will evolve conspicuous colours and patterns partly because these characteristics cannot readily evolve in profitable prey without close mimicry. The stability of this signal is maintained through the costs of dishonesty in profitable prey. Indeed, unprofitable prey will sometimes evolve a conspicuous form to reduce mimetic parasitism, even in the unlikely event that this form can be more closely mimicked. This is one of the first mathematical models of the evolution of warning signals to allow for the possibility of mimicry, yet our analyses suggest it may offer a general explanation as to why warning signals take the form that they do. Warning signals and mimicry may therefore be more closely related than is currently supposed.
|Institution:||The University of York|
|Academic Units:||The University of York > Biology (York)|
|Depositing User:||York RAE Import|
|Date Deposited:||19 Feb 2009 15:22|
|Last Modified:||19 Feb 2009 15:22|
|Publisher:||The Royal Society|