Dane Bailey
Research Mentor: Elizabeth Tibbetts
Mentor Department: Ecology and Evolution, LSA
Author(s): Dane Bailey, Seokin Yang, Emily Laub, Elizabeth Tibbetts
Session: Session 1 (9:00 AM – 9:50 AM)
Presentation Type: Poster 41
Abstract
Paper wasps are eusocial insects that display a clear separation of labor and shared nesting, in which individual castes differ greatly in reproduction and task specialization. Among the paper wasp colonies, the behavioral differences between the foundresses and workers are easily observed. However, the neural structures for each caste are not as well-understood, and finding connections between castes and neural development can lead to a better understanding of brain plasticity in general. This study compares relative brain region volumes between foundresses and workers of P. fuscatus to investigate how social roles and task specialization are associated with neural investment. During the summer, we closely observed wasp colonies in various nests across southeastern Michigan, and identified their caste. We then dissected, stained, and scanned the brains of individual wasps in each observed caste using micro-CT, allowing us to segment the brain regions with minimal uncertainty. We created 3D reconstructions using a computer segmentation program (3D-Slicer), and we will compute the surface area and volume of several brain regions within each wasp and identify significant differences in brain composition using statistical analysis. If social roles and task specialization affect neural investment, specific brain regions will vary significantly in volumetric measures between the roles because of the variance in skills required to fulfill each role. We hypothesize that in regions involved in learning and memory, such as the mushroom bodies, worker brains would show further development (greater volume and surface area) in comparison to foundresses because workers engage in more cognitively demanding tasks. These findings would indicate that differences in the neural anatomy (measurable volumetric changes) of paper wasps reflect behavioral specialization and support the hypothesis that neural investment is influenced by social role. Understanding these differences can help to guide future research in social roles, brain plasticity, and the evolution of social behavior in insects.
