PubMed Health⌕ Search

Biomedical subjects

C E Gasson

Publications and source records attributed to C E Gasson.

2 recordsLinked to original sources

Prey processing in central place foragers.

The importance of prey processing as an integral part of foraging behaviour has long been acknowledged, but little theoretical consideration has been given to the optimization of the processing behaviour itself. Processing renders food down to ingestible, palatable portions, and also removes non-essential mass thus reducing transport costs. Here, several models of processing are developed for a central place forager. When the forager has to make a simple choice between processing the prey and not, a critical distance from the central place can be calculated, beyond which it is optimal to process prey. If the forager also decides on how much of the prey to remove, the optimal amount to be removed can also be calculated. Imposing a ceiling on overall metabolic expenditure is shown to reduce the distances at which processing becomes the optimal strategy. The models are tested using parameters derived for a provisioning merlin, Falco columbarius, and alternative explanations as to why observed behaviours should differ from the optimal behaviour predicted are discussed.

Animals↗

Incorporating rules for responding into evolutionary games.

Evolutionary game theory is concerned with the evolutionarily stable outcomes of the process of natural selection. The theory is especially relevant when the fitness of an organism depends on the behaviour of other members of its population. Here we focus on the interaction between two organisms that have a conflict of interest. The standard approach to such two-player games is to assume that each player chooses a single action and that the evolutionarily stable action of each player is the best given the action of its opponent. We argue that, instead, most two-player games should be modelled as involving a series of interactions in which opponents negotiate the final outcome. Thus we should be concerned with evolutionarily stable negotiation rules rather than evolutionarily stable actions. The evolutionarily stable negotiation rule of each player is the best rule given the rule of its opponent. As we show, the action chosen as a result of the negotiation is not the best action given the action of the opponent. This conclusion necessitates a fundamental change in the way that evolutionary games are modelled.

Animals↗