Measuring visual acuity in bees from high-resolution images

About the Project

Visual acuity, the ability to perceive detail, is ecologically important, as it dictates what aspects of a visual scene an animal can resolve. Humans have some of the highest acuity in the animal kingdom, so we live in a perceptual world that is rich in spatial detail. Acuity, however, is highly variable, varying by at least four orders of magnitude across animals, meaning that the majority of animals cannot resolve as much spatial detail as we do. Despite acuity’s ecological importance, however, we know little about why this variation exists, and one unanswered question in most animal groups is whether there aspects of a species’ ecology that correlate with variation in acuity. This project will leverage high resolution photographs taken by the NSF-funded Big Bee Project (http://big-bee.net) to estimate acuity bees. Bees are an excellent group in which to examine variation in acuity, because they exhibit a wide range of lifestyles and ecologies. To measure acuity from a photograph, we must measure two parameters: the diameter of the hexagonal facets (ommatidia) that comprise the bee’s compound eye, and the eye’s radius of curvature.

For this project, students will begin with a set of images from approximately 50 species of bees. For each species, several photographs are available that view the bee from different angles. Students will use this dataset to develop algorithms for estimating the diameter of ommatidia and radius of curvature from a photograph. Students will use estimates to calculate acuity. If time permits, the project will explore potential correlates of acuity among aspects of bee ecology, for example nocturnality/diurnality, living socially or solitarily, and sex differentiation.