Effect of Temperature on Nestmate Recognition in the Ant Odontomachus chelifer

Abstract

Cuticular hydrocarbons play multiple roles in social insects. Their primary function is to waterproof the external surface of the body of individuals in order to prevent desiccation, however, they also act as a chemical signature in social insects, unique to each colony, through which individuals recognize themselves as nestmates. These compounds may undergo changes due to exogenous factors, aiming to maintain the integrity of the cuticle. However, changes in cuticular chemical composition may impair recognition among nestmates. Thus, this study tested the hypothesis that nestmates of the ant Odontomachus chelifer, when submitted to different temperature conditions, may undergo changes in their normal pattern of recognition. To do this, groups of workers were kept under two different temperatures, 15 and 30 °C, during a period of 24 hours, and then submitted to induced encounters with workers who remained for this same period at a temperature of 25 °C. As a form of control, the same type of encounter was performed between ants that remained isolated, but at the same temperature and also between ants from different colonies. The results show that ants that remain for 24 hours under different temperature conditions, present some level of difficulty in recognizing themselves as nestmates, performing more aggressive behaviors and taking longer touching themselves (antennation) than in the control condition.

Keywords

• behavior
• communication
• cuticle
• hydrocarbons
• Odontomachus
• waterproofing