Junior group leader University of Bayreuth Bayreuth, Bayern, Germany
Abiotic factors, such as fluctuations in air temperature, are known to majorly influence most animals. Poikilothermic insects in particular depend on appropriate temperatures to function optimally. Although previous studies have already shown that acoustic, vibrational, chemical, and visual communication signals can all be affected by changes in temperature, little is known about the impact these changes might have on specific behaviors. In mason bees of the genus Osmia, which emerge early in spring and are therefore subject to extensive temperature changes, females choose suitable males based on, among other criteria, their vibrations and chemical signals. However, research into the effect of temperature changes in these bees has so far focused on overwintering females. We, therefore, investigated if the environmental temperature has an influence on the male’s mating signals by measuring vibrations using a laser vibrometer. We further collected male and female odor at low and high temperatures and analyzed the cuticular hydrocarbons with gas chromatography. Our results clearly showed that both vibrations and odor profiles changed significantly with temperature. Furthermore, females responded differently to the changes depending on the modality of the signal. We conclude that temperature strongly influences the male mating signals and female response and therefore may have a major impact on sexual selection in this species. This is an important aspect to consider, not only in future studies on mating behavior but also in view of climate change.
