Genotype-specific habitat selection and thermal ecology in nucella lapillus (L.) (the dogwhelk)

Abstract

Nucella lapillus is a marine gastropod found all around the British coastline. Populations frequently display great polymorphism in the shape and colour of the shells. Shell shape is related to wave exposure but the forces maintaining colour polymorphisms are less clear. Populations from the north coast of Cornwall are shown to exhibit genotype-specific microhabitat partitioning, with lighter colour morphs being relatively commoner in sunnier sites and on average spending more time in the sun than darker morphs. This type of habitat selection has been claimed to be important in the maintenance of genetic variation and may explain some of the colour polymorphisms seen. © 1995 The Genetical Society of Great Britain.