Concept Learning in Honeybees (Apis mellifera): Color Oddity

In a wide variety of experiments, the performance of an invertebrate species, the honeybee (Apis mellifera), is similar to that of vertebrate species. That outcome is phenomenal considering their distant evolutionary relation and their remarkably different brain structures. While basic principles of learning appear similar between invertebrates and vertebrates, recent research has begun to explore advanced capabilities in honeybees, such as concept learning. In this experiment, the concept of oddity is examined. Foraging honeybees are trained to visit a laboratory window, where a set of ten colored circles is displayed on a horizontally-positioned computer screen. Nine are of the same color (yellow or white) and one is of the other color. Choice of the odd-colored circle is reinforced with sucrose solution, and choice of the non-odd circles is punished with salt solution. The honeybees are allowed to find the odd-colored circle, drink the sucrose solution, fly back to the hive to unload the solution, and then return to the window for the next trial. Honeybees are trained one at a time for 10 consecutive trials, in each of which there is a different configuration of the two colors. The color and location of the odd circle are balanced across trials. The honeybees show an increasing probability of choice of the odd-colored circle across the ten trials (significantly better than chance), suggesting concept learning of oddity in honeybees. Future studies will incorporate transfer trials with novel colors, in which honeybees that have learned the concept are expected to transfer their performance.