Summer 2019
In primitively eusocial Mischocyttarus pallidipectus paper wasp colonies, separation of members into reproductive castes is characteristic. Unlike many insects which are divided into morphologically and functionally distinct castes, M. pallidipectus castes are monomorphic: females on the nest are identical at emergence but will differentiate into castes by social dominance. The July 2019 field season in Monteverde, Costa Rica was devoted to testing the hypothesis that ovary size is correlated positively with dominance and connecting this to differences in individual chemical cues. In the field, I worked alongside a small team of researchers to locate wasp nests and observe individual wasp behavior for four hours each day over two days to identify dominance interactions and determine the social hierarchy of females. Following observations, the wasps were collected, and females were dissected. Female ovaries were photographed and measured in order to examine the behavioral data against the size and development of their ovaries. The gasters of each wasp were swabbed for their cuticular hydrocarbons which were then run on chromatography columns, allowing us to evaluate whether there is a difference in the chemical identity of females with and without developed ovaries.
In primitively eusocial Mischocyttarus pallidipectus paper wasp colonies, separation of members into reproductive castes is characteristic. Unlike many insects which are divided into morphologically and functionally distinct castes, M. pallidipectus castes are monomorphic: females on the nest are identical at emergence but will differentiate into castes by social dominance. The July 2019 field season in Monteverde, Costa Rica was devoted to testing the hypothesis that ovary size is correlated positively with dominance and connecting this to differences in individual chemical cues. In the field, I worked alongside a small team of researchers to locate wasp nests and observe individual wasp behavior for four hours each day over two days to identify dominance interactions and determine the social hierarchy of females. Following observations, the wasps were collected, and females were dissected. Female ovaries were photographed and measured in order to examine the behavioral data against the size and development of their ovaries. The gasters of each wasp were swabbed for their cuticular hydrocarbons which were then run on chromatography columns, allowing us to evaluate whether there is a difference in the chemical identity of females with and without developed ovaries.