Animals use multiple pieces of information from their environments to make decisions such as where to search for food, or which option is the best choice. How animals learn about available options has traditionally been studied in relation to a single reward (such as a particular food item). However, animals including humans often have to make decisions that vary in multiple types of reward. The research from this grant will determine how animals make these more complex types of decisions. To do this, bumblebees will be used: these bees visit a wide variety of flower types and in doing so learn to visit the most highly rewarding ones. The majority of research has focused on how bees learn and make decisions based on a single reward from flowers (nectar), despite the fact that bees collect multiple types of reward (the most common being nectar and pollen). This research will increase our knowledge of bumblebee foraging, which is particularly timely given recent bee declines. It will also more broadly inform our understanding of how animals, including humans, make complex decisions. The grant will support a postdoctoral researcher, a graduate student and undergraduate researchers. The research will be presented at national and international conferences, as well as to the public through a number of outreach events. Finally, 1-2 high school students per year will work alongside graduate students on research projects, with the aim of encouraging students from diverse backgrounds to pursue careers in science.
This project will address how multiple rewards affect cognition (learning, memory and decision-making), in three objectives. 1) It will be determined how learning is affected by multiple rewards through establishing how single vs. multiple rewards (nectar and pollen) affect how well a stimulus is learned, and the timing of reinforcement. 2) It will be determined how animals make decisions when choosing between options with multiple rewards, through addressing how bees make decisions between flowers that vary in nectar and pollen quality. For this objective it will also be determined whether absolute or comparative judgement is used. 3) It will be determined how bees? motivational state affects their memory of flowers with multiple rewards, by addressing whether motivational state when learning and remembering affects memory of reward or stimulus quality. All objectives will be carried out using lab- and greenhouse-based experiments with artificial flowers and commercial bumblebee colonies.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.