Studies on homing in the chiton Acanthozostera gemmata

Abstract

Feeding chitons were lifted and replaced in new positions to deny them the use of their outbrowsed trail in returning to their homesites. In 35 trials, homing occurred with a frequency of 0.66. Experiments were carried out to investigate the roles of the following: (a) airborne odour from the homesite, (b) topographical memory, (c) chemical cues from the current outward trail, (d) chemical cues from old browsing trails, and (e) "foreign" trails. Homesites whose immediate surroundings had been broken up retained an attraction which is not adequately explained. The appreciation of cues from old trails and a topographical memory are discussed as two possible factors involved in the homing mechanism.