Taina Conrad, Magdalena M. Mair , Julia Müller, Peter Richter, Sophie Schödel, Ann-Kathrin Weztstein, Sandra Steiger

Communication plays a fundamental role in the evolution of any form of cooperative behaviour such as parental care. However, it can be challenging to understand the specific role of certain signals and how they might have evolved into complex communication systems. To investigate what effect a lack of acoustic communication can have on brood care and offspring performance, we silenced parents of biparentally caring burying beetles with a non-invasive method and studied the effect on clutch and offspring performance. Moreover, by analysing three species with varying degrees of offspring dependency on parental care, we aimed to investigate how differing acoustic communication is related to the level of their dependency and if those two align in some way. We found strong effects of silencing parents on offspring performance in all three species. The lack of stridulations impacted offspring weight across all three species. However, our results point towards a species divergence in which development stage communication has the most substantial impact. Looking at larval weight at dispersal the effects seem to be in line with the larval dependency in the way we would have expected – with N. orbicollis being the most strongly affected, N. vespilloides being also affected and N. pustulatus not being affected. However, looking more closely, we found various differences at other time points and also larval survival being strongly affected in N. pustulatus. To date, only a few studies have looked at the exact function of acoustic signals during brood care with most of them focusing on what type of different signals are emitted rather than what effect they have. Our study is one of the first to start disentangling the interplay of communication and offspring performance.