Hive Mind
Making big decisions can be hard. Even after considering all options, doing research, and selecting the best solution, there’s always a fear that you chose wrong. To lessen that fear, a lot of us seek out advice from friends or even strangers on the internet in the belief that two – or better yet, many – minds are better than just one.
This way of decision-making is like having a “hive mind,” (not the fourth studio album by American R&B band The Internet, released on July 20, 2018, by Columbia Records – Hive Mind) where a large number of individuals share their knowledge which produces a collective intelligence.
This often leads to smarter decision-making among groups that is better than what one individual could accomplish alone. While often used in science fiction stories, hive minds do exist in real life. There are lots of great examples of this in nature, but one stands out.
And it comes from the animal that inspired the phrase “hive mind” in the first place: bees. These insects use nest-based communication to give their fellow bees important information, and collectively make robust decisions. But their methods of communication aren’t what you may expect.
Communication, or the passing of information from one individual to another, can take many forms. Many animals, such as primates, whales, birds, and wolves, use sound to talk to one another. Others, like many insects and even plants, use pheromones or chemicals to send messages. But bees have developed a communication method that’s a little more peculiar – hive mind.
They communicate via dance. And their dances can communicate to their peers the direction, distance, and quality of food sources, the location of possible new hive sites, and sources of nearby danger. And most surprisingly, they can even use their language to hold democratic debates.
This type of collective behavior is so powerful, and the connection between the bees is so profound, that scientists are beginning to understand that a bee colony acts a lot like a single organism – in fact, a lot like a human brain. And studying how these remarkable creatures interact could reveal answers about how our minds make decisions.
The Bee Dance
Although only about 10% of bee species are social, honeybees are very social indeed. Apis mellifera, or the Western honey bee, is the most common of the 12 or so honey bee species. They create large colonies with a single fertile queen, many non-reproductive female workers, and a small number of fertile males. Individual colonies can house tens of thousands of bees.
And all of the activity carried out by these bees is organized by complex communication between individuals. In the early 1900s, scientists believed that bees might communicate the presence of nearby food sources through scent – the fragrance of the flower adhering to the bees’ bodies and alerting the peers of its nearby presence.
By this theory, the other bees should simply search in ever-expanding circles until they discover the flowers with the memorized fragrance. But in 1944, Karl von Frisch, a professor at the University of Munich made a discovery that turned this assumption on its head – a discovery that would eventually win him the Nobel Prize.
Von Frisch noticed that after observing the returning scout bee, the other worker bees did not search for flowers with a matching scent everywhere around the hive, but only in the precise vicinity of where the foraging bee had been, even if that bee had been very far away.
Somehow, the exact location of the food source was being communicated by the bees. When von Frisch observed his bees more closely, he discovered that bees are constantly waggling, running, and turning in circles inside the hive. He then realized that this performance is a miniature reenactment of the bees’ recent flight outside the hive, indicating the location of the food source it just visited. Von Frisch had just discovered communication via dance.
And with it, foragers can share information about the direction and distance to patches of flowers full of nectar and pollen with other members of the colony. Their dance is called the waggle dance, and its main feature is the “waggle run,” where they waggle back and forth while running in a straight line. The duration of the run tells the other bees how far the resource is, where 1 second is equal to about 1000 meters. And the angle of their run, relative to a straight vertical line, tells the other bees the angle of the outward journey concerning the sun.
For example, if the dancing bee walks 45 degrees to the right of the vertical line, the food source is 45 degrees to the right of the position of the sun. In addition to dancing, the bee also gives out some of the flower’s nectar to its audience which, combined with the smell of the flower still lingering on the dancing bee helps the recruits locate the food source.
They communicate other things through dance as well. For instance, a “tremble dance,” where they rock forward and backward and side to side, tells others that foragers have brought so much nectar back to the hive that more bees are needed to process it into honey. But not every bee conversation is about food sources, and not every piece of communication is a one-way street, one bee communicating something to the rest.
Bees can use these same communication methods to discuss options about the future of the hive, and then make decisions democratically – a type of collective behavior very rarely seen in the animal kingdom.
A Democratic Debate
In late spring and early summer, honeybee colonies become overcrowded in their nesting cavities. When this happens, it’s time for them to find a new home. One-third of the worker bees stay put and rear a new queen. And two-thirds of the workers along with the original queen begin the search for a new nest site. The quest starts with the swarm congregating on a temporary site – a branch, or a bush outside the old hive.
From here, scouts will go out and look for suitable nest sites – a hollowed-out tree, or an abandoned chimney or birdhouse. The bees are looking for a place that will be protected from weather, predators, and is big enough for the new hive. Size is perhaps the most important since any colony occupying a hollow 10 liters or smaller can’t store enough honey to make it through the winter.
Once a bee finds a location that it likes, it comes back to the group and does the waggle dance, telling the others where the potential nest site is. Other bees then go check it out for themselves. If these recruits like it, they’ll come back and do the same dance, in the same direction. But it’s not always so clear which potential nest-site is the best choice. And this is where a vigorous debate begins.
Here’s an example of how these debates typically go down, taken from one of the first studies about bee debates in 1951. On the first day, 2 nest-scout bees were identified and labeled. One bee reported a nest-site candidate 1,500 meters to the north, while the other bee reported another site 300 meters to the southeast. The next day, 11 new dancers were identified.
3 danced in support of the site 1,500 meters to the north, 2 danced supporting the site 300 meters to the southeast, and 6 others danced about new sites altogether. The next day, it rained, and only 2 new dancers were recorded, one supporting the site to the north, and the other reported a new site, 400 meters to the southwest.
The next day, many new sites were reported, but interestingly, the site to the north was no longer being supported, perhaps because the rain leaked into the site showing it was not such a good candidate after all. Over the next few days, many sites were investigated and reported, but interest in most of them eventually faded.
Only one site, the one located 300 meters to the southeast, held the bees’ interest the entire time. By the afternoon of the 4th day, the bees dancing in support of the southeast site completely dominated, with 61 bees dancing for it, and only 2 bees still holding out for other sites. The next morning the decision was unanimous.
The swarm then launched into flight, flew 300 meters to the southeast, and took up residence in the wall of an abandoned building. By analyzing bee debates like this, the key features of the bee’s decision-making process become clear. The debate first starts with an information-gathering phase, where many alternatives are put on the table for discussion.
The debate then progresses with all or almost all the bees advocating for just one since indicating that a consensus has been reached. And during all of this, the process is highly distributed, involving dozens or even hundreds of individuals – all the hallmarks of a democratic process.
The dances they perform are complex and indicate a lot of cognitive ability. The bees have to remember the location of the resource or the nest site, as well as the location of the sun, and translate that information into the characteristics of the dance. The bees in the audience then have to read this behavior and translate it into directions they will then follow.
This, along with the coordinated decision to fly off in the same direction, at the same time, supports the idea that a bee swarm acts as if it is one organism – a superorganism. And recently, scientists have realized it’s even more profound than that. The way bees work together is a lot like how the individual neurons in the human brain work together. And studying their behavior may give insight into our minds.
A Collective Intelligence
Psychophysical laws explain the relationship between real-world stimuli and the perception of those stimuli. The brains of many organisms follow these laws, even quite simple ones. Weber’s Law states that the change in a stimulus that will be just noticeable is a constant ratio of the original stimulus. For example, it might take 4 pounds before you notice your backpack getting heavier if your backpack was already loaded with heavy books.
Hick’s law says that the brain is slower to make decisions when the number of alternative options increases. And Pieron’s Law says that the brain is quicker to make decisions when the options to decide from are of high quality. These laws help relate the brain’s perception of reality to actual reality and are important when making decisions.
Many organisms adhere to these laws, even simple animals like fish or insects. Fish, for example, can differentiate between a large school of fish and a small one, opting to join the larger one, as long as the size difference was large enough for them to be able to recognize it. But do these laws only explain an individual’s brain and behavior? Could these laws also apply to an entire colony of bees as one unit- the so-called ‘superorganism?’ In 2018, scientists started to get their answer or spotted insights about the hive mind.
They analyzed how quickly the colonies made decisions between sites of varying qualities and compared the data with several psychophysics laws to see how well the laws were adhered to. And it turns out, the bee colony followed the laws closely. It followed Weber’s law, in that the bees were able to choose the higher quality nest site, if and when the higher quality, such as a larger size, exceeded the minimum noticeable difference.
They also found that the bee colony was slower to make decisions when the number of alternative nest-sites increased and that the colony was quicker to decide between two high-quality nest-sites compared to two low-quality nest-sites.
Honeybee colonies adhere to the same laws as the brain when making collective decisions. These finds give more support for the idea that bee colonies exist as superorganisms, operating in the world much like a single, complete organism would. And just as the bee colony is similar to a whole brain, the individual bee thus acts as a single neuron. In the human brain, decisions are made when single nerves fire waves of electrochemical signals.
In bee colonies, decisions are made when individual bees communicate their discoveries through a visual display to other bees. And if bees follow the same laws as neurons, then observing them can lead to a better understanding of our minds – and more quickly too. Observing bee colonies is much easier than trying to observe the neurons of a brain while a human makes a decision. By understanding these parallels, we can start to learn just how psychophysical laws work.
And with more data, bees could teach us how our entire psychology arises from a few chemical actions from a few connected cells. And outside of understanding our minds, computer scientists have created lots of different algorithms based on bees’ decision-making methods. One popular decision-making model is the Artificial Bee Colony (ABC) algorithm. It is used for optimization problems, where users are looking for the best possible solution among many different options.
In this model, each candidate solution is like a food source and the quality of that solution is akin to the amount of nectar it holds. It begins with several employed bees at each of the food sources. They then go out to neighboring food sources and compare the amount of nectar to the previous source. They only remember the information of the best food source they find.
After a certain number of steps, they share their information with onlooker bees who then choose what they think is the best food source and sources that aren’t selected are abandoned. This continues until the best food source, or solution is identified.
This algorithm has been used to solve many real-world engineering problems across a variety of fields. For instance, electrical engineers have used it to determine the optimal position of solar panels for when they are in partial shade, aerospace engineers have used it to plan the re-entry trajectory of hypersonic vehicles, and computer scientists have used it to plan the path of robots, proving the true power of the hive mind.
The intersection of biology and computer science is an exciting one, as the different ways we can solve real-world problems with solutions that nature has already made are infinite. Algorithms are at the heart of this, and while they seem complicated, are easier to wrap your head around than you might realize, so it’s basically creating a system that can replicate the hive mind.