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Abstract

The term aposematism or "warning colouration" (as first characterised by Alfred Russel Wallace in 1877) describes the process by which defended organisms (animals or plants) advertise their unprofitability to potential predators to gain selective advantage. The first part of the thesis explores the relationship between evolutionarily stable levels of signalling and defence within the context of a game-theoretical, prey-predator setup in which the prey population consists of a single type. While it is implicitly assumed that the prey population is large enough to be considered effectively infinite the evolution of prey traits is also explored for intermediate-sized populations within the context of genetic algorithm approach. In the later chapters considerable effort is devoted to extending the mentioned predator-prey description to systems in which the prey population consists of two types, including a model and a mimic. This modification leads us naturally into the celebrated adaptive mechanism named after Henry Walter Bates, Batesian mimicry. In Batesian mimicry complexes individuals from a palatable (mimic) species resemble individuals from an unpalatable (model) species to gain protection against predators. While there is ample empirical evidence to suggest that individuals from one species may gain selective advantage by resembling individuals from another, the mathematical modelling of Batesian mimicry is rather limited. We predict that models and mimics can co-exist along a continuum of solutions (representing the conspicuousness, noxiousness, and average mimicto-model proportion) that are both ecologically and locally evolutionarily stable. We establish a number of novel results that confirm both common sense intuition and a considerable body of related works.

Publication Type:	Thesis (Doctoral)
Subjects:	Q Science > QA Mathematics Q Science > QH Natural history > QH301 Biology
Departments:	School of Science & Technology School of Science & Technology > Mathematics Doctoral Theses

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