August 13th, 2024
Written by: Serena Chen
As summer comes to an end, it is soon time to say goodbye to the little black and yellow creatures that you may have spotted on your neighborhood flowers this year. Bees are famous for being important pollinators and contributors to the environment, but did you know that they are also incredibly intelligent insects? Bee brains are only the size of poppy seeds and contain about one million neurons1 – far less massive than the human brain which contains one hundred billion neurons2. Yet, bees are capable of many complex behaviors that humans are also familiar with, including social, navigational, and communication behaviors1. Bees can also form memories and make quick and accurate decisions3, making them highly interesting to neuroscientists who study cognition. Insight from bees’ tiny brains might also aid in the development of AI and decision-making robots4. Taken together, there is a lot you may not have known about these little neighbors that could tell you more about your own brain and what it’s capable of.
Communicating with one another
Bees live in groups called colonies which include individuals from multiple generations, one defining trait of what scientists refer to as eusocial insects5. While not all members of the colony reproduce, they still cooperatively bring up the young5. Many types of jobs exist to maintain the colony. For example, foragers are bees whose job is to leave the hive in search of resources like food6. Just like in any family, effective communication is key to a well-functioning colony. Different types of bees have various ways of communicating with one another. Foraging honeybees and bumblebees, for instance, like to communicate the approximate location of a food source to their friends by performing the waggle dance, where they signal the distance and direction of the food source by the duration and orientation of the dance7. Other bees can decode this message and send more bees to the precise location of the food source7. If bees successfully discover a food source, they may also pump their wings and release a chemical substance which alerts other bees to leave the hive in search for the available food8 – another creative method of communication within the colony. Additionally, honeybees can use the sun’s position in the sky to obtain compass information during their excursions for food outside the hive7, showing their talent as navigators.
What allows bees to be good communicators? Since bees generally perform the waggle dance after locating a food source, neuroscientists believe that a bee’s individual motivation to perform this dance is linked to the hunger state of their colony9. These scientists found that when a colony was starved, this led to increased levels of certain chemical signals in the brains of foragers10. This included a neurotransmitter known as dopamine10. Dopamine is well-known to be involved in neural pathways driving the positive feelings you get when you anticipate or receive a reward11. Thus, increased dopamine in bees upon starvation suggests that bees are similarly motivated by an expectation of a food reward when they leave for foraging10. Changes in dopamine levels were also observed in bees performing the waggle dance, implicating the importance of this neural signaling pathway in motivating individual bees during their process of communication10.
Decision-making on the fly
A simple excursion outdoors may not seem like a daunting task, but bees have limited energy and time before returning home. Thus, they are required to make rapid and accurate assessments about which flowers will likely offer them the most nectar or pollen before they land3. One study found the average time for bees to decide which flower to land on was only 0.6 seconds3,4, faster than even the average human can make decisions4. More impressively, this assessment of which flower landing would be the most fruitful was accurate most of the time3, suggesting bees also know how to consider and reduce risks when making decisions. This level of sophisticated decision making is comparable to that of primates3. With bees’ brains only being a fraction of the size of primates’, understanding how they can still possess certain cognitive abilities and motivational pathways, which even humans are familiar with, may provide great insight into the vast capabilities of the brain.
Bee brains as a model for robots
Have you ever considered that nature may inspire the future of AI and robotics industries? With how much bees’ brains can achieve despite their size, they may be a promising model for generating robots with efficient decision-making capabilities that require minimal power3. This is something scientists are currently exploring, developing computational algorithms that, like bees, can gather and sample information to produce a split-second ‘accept’ or ‘reject’ decision upon being given a sensory input3. The ability for robots to achieve something like this could potentially make them more independent.
Overall, bees are highly intelligent eusocial insects. While they are already famous for being nature’s hardest works, learning about them may help expand knowledge of the even the human brain, far more than you may have previously imagined.
References
1. Menzel, R. The honeybee as a model for understanding the basis of cognition. Nat. Rev. Neurosci. 13, 758–768 (2012).
2. Gulati, A. Understanding neurogenesis in the adult human brain. Indian J. Pharmacol. 47, 583–584 (2015).
3. MaBouDi, H., Marshall, J. A., Dearden, N. & Barron, A. B. How honey bees make fast and accurate decisions. eLife 12, e86176 (2023).
4. Baisas, L. Bee brains could teach robots to make split-second decisions. Popular Science https://www.popsci.com/science/bee-brain-decision-making-robot/ (2023).
5. An Introduction to Eusociality | Learn Science at Scitable. https://www.nature.com/scitable/knowledge/library/an-introduction-to-eusociality-15788128/.
6. Klein, S. et al. Honey bees increase their foraging performance and frequency of pollen trips through experience. Sci. Rep. 9, 6778 (2019).
7. Kohl, P. L. & Rutschmann, B. Honey bees communicate distance via non-linear waggle duration functions. PeerJ 9, e11187 (2021).
8. Alves, D. A. et al. Diverse communication strategies in bees as a window into adaptations to an unpredictable world. Proc. Natl. Acad. Sci. U. S. A. 120, e2219031120.
9. Ai, H. & Farina, W. M. In search of behavioral and brain processes involved in honey bee dance communication. Front. Behav. Neurosci. 17, 1140657 (2023).
10. Huang, J. et al. Food wanting is mediated by transient activation of dopaminergic signaling in the honey bee brain. Science 376, 508–512 (2022).
11. Bromberg-Martin, E. S., Matsumoto, M. & Hikosaka, O. Dopamine in motivational control: rewarding, aversive, and alerting. Neuron 68, 815–834 (2010).
Cover photo by Ethan Ta, student at the University of Pennsylvania.
‘Waggle dancing honey bee!’ video by Flow Hive on Youtube.
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