Corners and bubble wrap: the structure and texture of surfaces influence crayfish exploratory behaviour

B W Patullo,D L Macmillan

doi:10.1242/jeb.02020

Abstract

Touch is a principal sense in all animals. It is potentially important in species of freshwater crayfish that encounter murky waters or are nocturnal. Little is known about how tactile (touch) stimuli affect exploratory behaviour under these conditions. We placed animals in different tactile situations at the start of an exploration in a dark arena and tracked the position of the body and antennae to test whether subsequent search behaviour was affected. Individuals were exposed to differently textured walls, channelled out along a wall, or released in contact with no, one, or two walls. A corner arrangement of surfaces, where individuals started near two walls at right angles, produced behaviour that differed from that of other configurations; animals chose one wall and then maintained a close distance from the wall along which they were moving. The distance from a wall adopted by a crayfish walking parallel to it was affected by the texture of the wall. These results on the influence of tactile stimuli on crayfish exploratory behaviour may have implications for other taxa.

Highlights

Many animals use touch to interpret the surrounding environment
A number of crayfish species are most active during dark hours, e.g. Procambarus clarkii (Page and Larimer, 1972), Orconectes virilis (Hazlett et al, 1979), Astacus astacus (Abrahamsson, 1983), Cherax destructor (Merrick, 1993), Austropotamobius pallipes (Barbaresi and Gherardi, 2001)
We focused on changing the type of thigmotactic environment in which an animal started its exploration to test whether wall-following is a stereotyped response in this species

Summary

Introduction

Many animals use touch to interpret the surrounding environment. The way in which tactile (touch) stimuli are used have been studied in a range of species, e.g. crayfish (Zeil et al, 1985; Schmitz, 1992), rats (Carvel and Simmons, 1990), lobsters (Wilkens et al, 1996), cockroaches (Camhi and Johnson, 1999; Okada and Toy, 2000), moles (Kimchi and Terkel, 2002) and humans (reviewed by Goodwin and Wheat, 2004). The location of an object can be determined by combining the input from the receptors activated at the point of contact with that of position sensors associated with the joints of the appendage. This active touch, or ‘tactile’ perception, is referred to as a haptic sense and the performance of some species resembles haptic perception in humans Even animals that are active during daylight may experience low light and turbid waters In these circumstances, they may be dependent on non-visual information from chemical and tactile sensory systems to move about and orientate

Results

Discussion

Conclusion