Abstract
The expression of alternative traits that benefit eusocial individuals but
are not directly involved in reproductive differences among those individuals,
which I call ‘eusocially selected traits’, may vary in response to
environmental changes if this increases an individual’s inclusive fitness.
In this study, I describe traits that separate individuals within the reproductive
division of labor of Mischocyttarus mexicanus, a eusocial paper
wasp, and determine whether observed eusocially selected traits vary
across seasons. I examined M. mexicanus because females initiate new
nests throughout most of the year where they experience different conditions
depending on the season. Findings from this study suggest two
main conclusions: (1) phenotypic differences among M. mexicanus
females are mixed, showing specialized, generalized, and contextdependent
eusocially selected traits and (2) a female’s position within
the reproductive division of labor may be influenced by its state. The
presence of context-dependent traits, e.g. large females initiated solitary
nests in the spring and grouped nests during the summer, suggests that
the payoff for pursuing different positions within the reproductive division
of labor changes across seasons. The expression of context-dependent
eusocially selected traits also suggests that, roles, instead of castes,
may better reflect the reproductive division of labor among individuals
of eusocial species like M. mexicanus.