The effect of social isolation on offspring performance: an evolutionary, ecological and molecular perspective

• Applicant: Professorin Dr. Sandra Steiger
• Subject Area: Evolution, Anthropology ; Sensory and Behavioural Biology
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 508884109

Family life is a taxonomically widespread phenomenon that entails multifaceted interactions among family members. Especially, parent-offspring and sibling interactions have been hypothesised to affect each other leading to different types (cooperative, neutral or competitive) and roles of interactions during the evolution of family life. However, due to a past focus on animal systems, in which family living is highly derived and obligate, we still lack information about the role of the various social interactions and their interplay in the evolution of family groups. To address this gap of knowledge, we propose to take advantage of an intriguing model system, the burying beetle system, in which closely related species differ immensely in their reliance on parental care. Isolating offspring from family members will thereby serve as a central tool to obtain insights into the type, degree and interplay of social interactions. By analysing the combined and separated effect of social isolation of offspring from parents and siblings, we will examine whether the type and degree of sibling interactions is different in the absence than in the presence of parents and whether characteristics of sibling interactions changes when offspring become more or less dependent on parental care. Since it has been hypothesised that sibling cooperation evolved to compensate for a decreased benefit of care, we will specifically test whether species which rely less on the presence of parents, rely more on the presence of siblings. Furthermore, we will analyze how harsh environmental conditions (high and low temperature, low food availability, high microbial load) affect responses to social isolation and whether both parent-offspring as well as sibling cooperation can buffer against low environmental quality. In the final part of the project, we will study the genetic underpinnings of parent-offspring and sibling interactions. Specifically, we will compare gene expression patterns of offspring that had been isolated from siblings and/or parents and examine gene expression responses to short term parental separation among three species that differ substantially in the degree of offspring dependency on parental care. The result of the proposed project will not only shed light onto the intricacies of family interactions and their changing roles during the evolution of family life but will also enhance our general understanding of the consequences of social isolation on offspring performance.

• DFG Programme: Research Grants
• Co-Investigators: Dr. Maximilian Körner; Dr. Heiko Vogel