Acclimation in ants: Interference of communication and waterproofing through cuticular hydrocarbons in a multifunctional trait

Organismal traits may experience conflicting selection pressures if they fulfil different functions simultaneously. This can require trade-offs between functions or alternatively functional separation between elements of the trait.
An important multifunctional trait in insects is the cuticular hydrocarbon (CHCs) layer. CHCs cover the body of nearly all insects, protect against desiccation and serve as a communication signal. In social insects like ants, they provide cues for nestmate recognition. To maintain their waterproofing function, insects have to adjust CHC composition to current temperatures. These changes might affect information content and interfere with communication, which would be especially detrimental in social insects.
Here, we studied how acclimation affects nestmate recognition in two sister species of the ant genus Lasius. Colony fragments were exposed to three climate regimes. We analysed behaviour towards same and differently acclimated conspecifics, and determined...