Department of Biology and Biotechnology

The Gegear Laboratory

Research

 

Our ongoing research projects are outlined below.

1)  Pollinator cognition and the evolution of multi-component floral displays

Animal-pollinated plants produce complex floral displays that
combime stimuli within and among sensory modalities (visual, olfactory, somatosensory).  Although it is widely recognized that the basic function of floral display is to help plants obtain an animal pollinator to transport and receive pollen (male gametes) for reproduction, the adaptive significance of display complexity remains unknown.  Given that plants incur reproductive costs when pollen moves between flowers of different plant species (pollen wastage and stigma blockage), the ideal pollinator from the plant’s perspective would specialize on the flowers of a single species while searching for food resources (nectar and pollen).  Our research examines how plants use display complexity to manipulate pollinator decision-making processes in a manner that would make adopting a specialist foraging strategy a better economic option than a more generalist strategy.  Our central idea is that floral display complexity increases foraging costs to pollinators due to limitations on the capacity of their cognitive system to effectively acquire, store, and process multi-dimensional and/or multi-modal sensory information.  In this view, complex floral displays represent a co-evolutionary compromise between the interests of the plant (maximize reproductive output) and their animal pollinator (maximizing energetic gain).

2)  Cognition, behavioral flexibility, and the response to human-induced environmental change

Many animal species are experiencing rapid and novel changes to their habitat due to human activity. While these changes are having a devetating effect on some species, other species remain unaffected or are even expanding in range and number. We are using pollinators as a model to understand how and why species vary in the response to rapidly changing and novel socio-ecological conditions. Our current work aims to 1) identify cognitive mechanisms that enhance the ability of individuals to flexibly adjust their behavior to novel resource conditions, 2) quantify differences in the capacity for behavioral flexibility among species, and 3) determine ecological selection pressures that drive the evolution of high behavioral flexibility levels in natural populations.

3)  Conservation behavior of plant-pollinator interactions

Bumblebees are considered keystone species in
many natural and agricultural ecosystems due to the vital pollination service that they provide to outcrossed flowering plants.  However, many species are in a state of unprecedented decline, posing a serious threat to biodiversity, food security, and the agro-economy.  Although the exact cause of these declines is currently unknown, it is generally agreed that sub-lethal effects (i.e. those that do not cause direct mortality but alter behavior in a way that reduces fitness) of chronic exposure to two anthropogenic stressors - systemic ‘neonicotinoid’ pesticides and novel diseases/pathogens - are significant contributing factors.  Our research investigates how exposure to these stressors impacts cognitive mechanisms and consequently performance of fitness-related behaviors.  Our working hypothesis is that bumblebee species in decline are more susceptible to stressor-induced impairments to cognitive functions thereby rendering individuals less able to respond adaptively to novel anthropogenic change.