Visual learning performance of non-pollen and pollen foragers in Bombus pauloensis bumblebees

Despite its economic and ecological importance, little is known about the learning abilities of the South American bumblebee Bombus pauloensis. To date, no studies have explored the visual learning capacity of its foragers, potential differences between non-pollen and pollen foragers, the effect of body size on learning, or male learning abilities. Here, we investigated the visual learning performance of workers, taking into account forager type (pollen versus non-pollen foragers) and body size. As a complementary analysis, we assessed the same variables in males. Our results show that both female foragers and males of this South American bumblebee can learn to associate a specific color with a sugar reward and do not exhibit color bias for the tested colors (blue and yellow). We found no significant differences in color learning ability or body size between pollen and non-pollen foragers. Additionally, body size significantly influenced visual learning performance during the testing phase. This study provides new insights into the visual learning abilities of both foragers and males in the South American bumblebee Bombus pauloensis, enriching the understanding of cognition of native pollinators.