How does early-life social environment influence adult behaviour and morphology?
Supervisor: Christine Miller
Co-Supervisor: Eleanor Bladen
Project Summary (MPhil):
Intraspecific social interactions are prevalent across the animal kingdom. Sometimes these begin when the animal is born or hatches, and they are in contact with their family members. But how do the social interactions that animals experience early in life affect their behaviour, morphology and, ultimately, breeding success when they reach adulthood? And what are the mechanisms behind any influences we do see? Researching the long-term effects of early-life social interactions can help us understand the evolutionary causes and consequences of social behaviour, as well as the ecological implications for individual populations exhibiting variation in their levels of social behaviour.
The project will focus on Leptoglossus zonatus, which is a highly polyphagous species of leaf-footed bug found across the southern USA, central America and South America. It is a generalist feeder on a vast array of economically important crops, using its piercing-sucking mouthparts to inject saliva into plant tissue and suck out nutrients, causing damage to developing seeds and fruits, and acting as a vector of plant pathogens (Broadhead et al., 2024; Schaefer & Panizzi, 2000). For this reason its advancing geographic range is causing increasing concern.
While there is a wealth of literature on the impacts of its crop impacts and various aspects of its physiology, seasonal timings and feeding behaviour, there is a lack of research on its social behaviour. However, nymphs show aggregation behaviour and unpublished data from the Biotic Interactions Group show that L. zonatus individuals that are reared alone during their nymphal stages are far less likely to develop to adulthood than those kept in sibling groups, indicating that early-life social conditions strongly influence their fitness. Therefore, learning more about the ecology behind, and consequences of, their early-life social interactions will be key to understanding their population dynamics. Research in L. zonatus and other leaf-footed bugs has indicated the importance of symbiont acquisition in successful development to adulthood (Umanzor et al., 2025), but while there is no evidence for vertical transfer of symbionts in this species (Hunter et al., 2022), the role that conspecifics play in horizontal symbiont transmission during development is an unstudied and exciting avenue for future study.
This project will address three key questions:
1) How do social interactions during development affect survival to adulthood, and adult morphology and breeding behaviour?
2) Do early-life social interactions facilitate symbiont transfer?
3) Is the composition (with regards to age, relatedness and species) of aggregations in early-life important for successful development?
Type of work:
This project will be entirely lab-based in the Department of Zoology, University of Cambridge. We will have a lab colony of L. zonatus which the successful applicant will be responsible for maintaining and using for experiments. The student will rear and care for insects and conduct experiments testing effects on behaviour and morphology.
Importance of the area of research concerned:
In focusing on these questions the MPhil student will be helping to advance our understanding of how social interactions evolve and are maintained, and will make useful insights that are relevant to pest-control and food security.
References:
Broadhead, G. T., Cottrell, T. E., & Beck, J. J. (2024). Leaffooted Bugs: Insect Pest Species of Growing Concern for Agriculture. Journal of Agricultural and Food Chemistry, 72(5), 2467–2472. https://doi.org/10.1021/acs.jafc.3c06763 Hunter, M. S., Umanzor, E. F., Kelly, S. E., Whitaker, S. M., & Ravenscraft, A. (2022). Development of Common Leaf-Footed Bug Pests Depends on the Presence and Identity of Their Environmentally Acquired Symbionts. Applied and Environmental Microbiology, 88(5), e01778-21. https://doi.org/10.1128/aem.01778-21 Schaefer, C. W., & Panizzi, A. R. (2000). Heteroptera of Economic Importance. CRC Press. https://books.google.co.uk/books?id=Xw9CEQAAQBAJ Umanzor, E. F., Kelly, S. E., Ravenscraft, A., Matsuura, Y., & Hunter, M. S. (2025). The facultative intracellular symbiont Lariskella is neutral for lifetime fitness and spreads through cytoplasmic incompatibility in the leaffooted bug, Leptoglossus zonatus. Frontiers in Microbiology, Volume 16-2025. https://doi.org/10.3389/fmicb.2025.1595917