Meeting Abstract
Chemical cues and signals are essential components of numerous behaviors among squamate reptiles, especially snakes. Tongue flicking allows transfer of chemical cues to the vomeronasal organ and the accessory olfactory bulb. Past studies have suggested that several species of snakes can discriminate chemicals deposited by themselves, conspecifics, or clean controls. Is this a measure of self-recognition? Most studies have used visual recognition, using a mirror. However, animals relying on different types of cues may use non-visual means of self-recognition. Prior snake studies, while suggestive, lacked controls, such as for diet and genetics, and video recording. We carried out a study on 24 juvenile eastern garter snakes, Thamnophis sirtalis, with an even sex ratio, from a single litter. We manipulated substrate chemicals in test arenas using clean or previously occupied cage liners and measured the frequency of tongue flicking and general activity. Each snake was tested under four conditions: one’s own substrate, substrate of a same sex littermate fed the same or different diet (fish or worm), or a control clean substrate. Trials lasted 30 minutes, were video-recorded, divided into three 10-minute segments, and both tongue flick and activity counts tallied for each segment. We found that tongue flick and movement rates were consistently lower in the own chemical vs the control condition, replicating prior findings. We also found sex and diet differences with regard to tongue flick rates to own vs conspecific chemicals of snakes fed identical diets. These appear to be the first data showing sex differences pre-reproductively.
