A bumblebee’s brain is incredibly small—smaller than a sesame seed—but its intelligence is surprisingly advanced. As Felicity Muth, researcher at National Geographic Explorer, explains “Bumblebees are capable of many of the same cognitive feats as many vertebrates”.
Muth, who previously studied bird behavior, now focuses on the cognitive abilities of bumblebees: how they learn, how they choose which flowers to visit, and what motivates them. Her goal is to understand how these insects perceive and interpret the world around them.
One of the most fascinating aspects of Muth’s work is the interaction between bumblebees and plants, which goes beyond a simple exchange of nectar. Plants reward bees with nectar rich in sugars, incentivizing them to visit other flowers of the same type and transport pollen, thereby aiding the plants’ reproduction. However, some plants go further, attempting to manipulate the bees into returning multiple times, often trying to minimize the amount of sugar they must produce.
An interesting example involves flowers that contain caffeine. According to Muth, the caffeine in flowers not only makes bumblebees more likely to remember a particular flower, but it also causes them to fly faster, increasing the number of flowers visited in a short time. Other chemicals, such as octopamine and tyramine, which act as neurotransmitters in the brains of insects, can alter these effects.
In the lab, Muth has studied these phenomena by creating artificial flowers filled with carefully mixed nectar and chemical cocktails. Her research revealed that when bumblebees drink nectar containing caffeine, they perceive more sugar than there actually is, increasing the likelihood they will return to that flower. However, if the nectar also contains octopamine and tyramine, the effect of caffeine is partially nullified.
In addition to lab studies, Muth and her team also capture wild bumblebees in alpine meadows throughout California’s Sierra Nevada. Using nets, they catch the bees and place them in transparent containers, where they are subjected to experiments to test their learning and memory abilities.
One of the most interesting experiments Muth conducted was in 2021, alongside Anne Leonard from the University of Nevada. In this study, they tested the ability of bumblebees to associate specific colors with sugary food. The results showed that both female worker bees and male bumblebees were equally capable of learning, though males were slower to make decisions.
A surprising observation involved the bumblebee queens, which emerge from hibernation in early spring for a brief period to forage before establishing a new colony. Muth found that the queens were significantly faster learners than the worker bees. “They have to move fast, they have to be smart”, Muth explained, noting that the pressure on queens to start a new colony quickly makes them more adept at adapting to and responding to challenges in their environment.
In 2024, Muth continued her investigations, shifting focus from color to the ability of bumblebees to associate specific odors with food. While the results are still preliminary, it appears that queens continue to learn faster than workers. Muth believes that this accelerated intelligence may be linked to the unique challenges queens face: not only foraging for nectar but also selecting mates and nesting sites, all of which require specialized cognitive abilities.
Muth suggests that queens may have a form of “cognitive specialization” that goes beyond merely being larger than the workers. Their brains may be adapted to the specific difficulties they encounter in their lifecycle.
Muth’s work is not only revealing the cognitive mysteries of bumblebees but also raising broader questions about the evolution of intelligence in animals. As the researcher explains, “If we could understand how obstacles and challenges shape the intelligence of these insects, we might better understand ourselves”. Her findings could shed light on how intelligence evolved not only in insects but also in other animals, including birds, mammals, and possibly even humans.
Muth’s research on bumblebee learning is supported by major organizations, including the National Geographic Society and the Templeton World Charity Foundation, as part of a broader initiative on wildlife intelligence.
Over time, Muth hopes her discoveries will not only uncover the secrets of insect cognition but also help answer fundamental questions about the nature of intelligence across the animal kingdom.