A mathematical consideration for the optimal shell change of hermit crab

Sato Yoko

Seno Hiromi

Journal of Theoretical Biology

Shell of the adult hermit crab has some important roles for its fitness. In the same time, the shell size often limits the body growth of its owner. To grow the body size larger, the individual must change the shell to another larger shell. If the individual cannot get another larger one, the individual has to suppress the body size growth as the occupied shell size allows. Growth suppression would result in the lower fitness. With a simple mathematical model, we consider the criterion about whether the individual should try to change the shell or not in order to get the higher fitness. We show that the optimality of a shell change behavior has a relation with the body size and the season length for the shell change. They also affect the optimal timing for the shell change. It is implied that the probability of the success in a shell change and the cost for the shell change behavior do not affect the optimal timing for the shell change at all but significantly do the optimality of the behavioral choice.

hermit crab

optimal behavior

optimal timing

body size

mathematical model

Mathematics [ 410 ]

eng

Elsevier

Copyright (c) 2005 Elsevier Ltd.

[ISSN] 0022-5193

[DOI] 10.1016/j.jtbi.2005.08.019

[NCID] AA00708258

[DOI] http://dx.doi.org/10.1016/j.jtbi.2005.08.019 isVersionOf