NSF Postdoctoral Fellowship in Biology FY 2021: Identifying the mechanisms that link social environment to physiological plasticity in an incipiently social orchid bee

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2021, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. This research examines how fundamental aspects of social behavior evolved in eusocial insects (such as honey bees and ants where there is only a few reproductive adults within a large colony), leading to their success across diverse ecosystems.

This research will use orchid bees, close relatives of honey bees that form social groups of only two or three individuals, to perform experiments, varying social conditions to understand how basic social interaction influences physiology. This work fills a gap in our understanding of social evolution by exploring how physiology first becomes sensitive to social environment, an important step in the evolution of the specialized queens and workers of eusocial species.

This research will involve outreach in collaboration with Florida public nature centers as well as community science projects documenting orchid bee nesting across Florida.

Eusocial insects exhibit remarkable phenotypic plasticity, with individuals capable of altering behavior and physiology in response to changes in their social environment. This is demonstrated by worker individuals that inactivate their ovaries in response to the presence of a reproductive queen. Although this socially regulated physiology is found across eusocial species, little is known about the mechanisms that link social environment to physiology in the early stages of social evolution.

This understanding is hindered by the lack of model systems that are closely related to eusocial species while still retaining a simple social structure. In this study, using the orchid bee Euglossa dilemma, a close relative of honey bees that forms small social groups of two or three, the fellow will 1) identify the social stimuli that regulate physiological plasticity and 2) uncover the links between this plasticity and social environment.

First, an experiment will be conducted, varying the age of brood and the timing of adult social interaction to examine how social environment mediates physiological plasticity. Second, gene expression and hormone levels will be assessed to test the hypothesis that social cues are detected by the antennae, integrated in the brain, and then communicated across tissues via specific hormone pathways.

This work will allow the fellow to develop Euglossa dilemma as a model for social evolution and involve training of undergraduate and graduate students in molecular techniques.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.