Honeybees, Apis mellifera, demonstrate an ability to perform visual learning to such an extraordinary extent that it is not typically associated with smaller brains. Those learning abilities may be linked to their degree of sociality as they aggregate into colonies and synergistically work together on tasks. The Social Brain Hypothesis suggests that an organism's level of intelligence is correlated to how social their environment is. Some bees like the leaf cutter bee, Megachile rotundata, are solitary bees who do not live in a hive but instead reside in individual nests. The purpose of this research is to explore the visual learning capability of leaf cutter bees and compare them to the learning capability of the well documented honeybee. The methods used for this study include placing a tethered bee on a free rotating ball that is placed in front of a screen. Two colors are projected onto the screen and the bee controls the movement of the shapes. A positive and negative reinforcement are assigned to each shape. By analyzing how many times the bee picked each color, how fast it responded to the shapes, and how far from a distance it walked to fixate on that color, we can make an informed statement about the solitary bee’s ability to visually learn. We anticipate one of three outcomes, the leaf cutter bee will either have a greater learning rate, less learning rate, or equal learning rate to that of the honeybee. These results will help supplement more data for the Social Brain Hypothesis and allow a deeper understanding of how sociality is related to cognition. This study also has major relevance to pollination practices as leaf cutter bees are used in agriculture, therefore understanding the neural basis of cognition can open the door for new reforms in crop pollination.

It’s known that plant-pollinator relationships are central to the proper functioning of agricultural and ecological systems. Of the many navigation pathways pollinators use, floral scent signaling for insects is the most complex yet also the most at-risk from atmospheric human activity. Oenothera pallida, a primrose, interacts with the pollinators Hyles lineata, a hawk moth, and Megachile rotundata, a leaf-cutter bee, via this scent pathway. Because of their reactivity with floral scent, human-released ozone and NO₂ are the main perpetrators of scent degradation. To understand this relationship being damaged, I exposed the moth and bee species to a normal Oenothera scent versus a degraded one, recording the antennal response as well as the behavioral, expecting a poorer response to the degraded scent. Moth antennae act as the site of odor reception, bearing sensory hairs that detect odors, allowing the moths to navigate to scent sources. I conducted electroantennographic experiments (EAG) to record the electric signal from the insect antennae in response to each scent blend, with the degraded scent representing the impact of NO_x interactions. Following the EAG, I conducted Proboscis Extension Reflex (PER) experiments with Megachile to show the relationship between insect behavior and antennal physiology when in the presence of the scent blends. I expect that the EAG experiments show that the antennae respond worse to NOx degraded scents in comparison to the normal, unaltered scent blend. Likewise, Megachile has a worse PER when exposed to the degraded scent, linking the chemical biology of the scent interaction to the feeding and pollination behavior. This work has broader implications regarding the importance of plant-pollinator relationships, especially when considering environmental and agricultural health as well as the issue of food security in our changing climate.