The divergence of mobility and activity associated with anti-predator adaptations in land snails

Abstract

The extreme divergence of phenotypes between two closely related terrestrial gastropods, Karaftohelix editha and K. gainesi (Camaenidae, Stylommatophora), has been suggested as a result of anti-predator adaptations because K. editha and K. gainesi showed shy and bold anti-predator behaviours, respectively. In this study, we measured the crawling speeds in the laboratory and the exploration (the crawled distances during every 6 h) and the activity (the active/inactive statuses) in the field for each species. As a result, K. gainesi crawled faster under ordinary conditions and moreover upregulated its crawling speed 1.21–1.28 times after the stimulus. The activity pattern of K. editha was typical of nocturnal species, but K. gainesi remained active even under daylight. These results might suggest that K. editha and K. gainesi were deemed as shy/inactive and bold/active species, respectively, and that behavioural syndromes existed between shyness–boldness and activity personalities.