I finished reading Thomas D. Seeley’s excellent book Honeybee Democracy this past week, and it has me thinking about bee colonies as superorganisms. The idea is that a specialized colony of animals such as termites, coral, or bees behaves as a single organism, and can be treated as such. This had me wondering how a bee colony compares to our own special type of organism, the human body, which in turn led to this post.
Systems in Humans
A quick search found the following list of major systems in the human body, so the question here is how might these express themselves in a honey bee colony.
There is a book The Buzz About Bees about bee colonies as superorganisms. This is on my list of books to read, as I hear it is quite good, so if you want the scientific discussion skip this post and go read the book. Otherwise, please humor my musings, and let’s treat these bodily systems as representative of organisms in general. So how do these translate into the colony? Here is my take.
A body is a collection of cells, specialized to perform specific functions. For a bee colony, there are three types of cells: a queen, workers, and drones. So one amazing point is that worker bees take on the specialization required to perform most of the system functions for a colony. The organism, in my view, encompasses the entire hive, from the hive body down to the individual honey comb cells.
Our first system moves blood throughout a body, and individual bees certainly have their own internal circulatory system. Without the cardiovascular system we’d have no way to move oxygen and other nutrients throughout our bodies. So as a superorganism, does a colony have a system to transfer nutrients and other necessary resources around the hive?
A definite yes. Foraging bees pass their nectar, pollen, and plant resin to bees in the hive, who in turn carry these resources to storage cells or to other bees. In the winter, the bees take advantage of warm days to move food around the colony so it is nearby on cooler days when they are tucked tight in their cluster. You can just imagine these critical resources circulating around the hive from mouth to mouth and cell to cell.
A colony’s digestive system is a combination of bee stomachs and colony maintenance. Incoming nectar is treated by one or more bees with enzymes that break down the nectar into the sugars that form honey. The water-laden liquid is stored in cells and the internal air currents generated by the bees evaporate this liquid into honey. So the processing of nectar into honey is definitely an activity dependent on the entire colony.
The endocrine system in humans and animals controls hormones and other chemicals that regulate various aspects of the body, from growth and drowsiness to sex drive and bone construction.
Similar, a bee colony is a finely tuned system of chemicals. The queen produces queen substance that is shared by bees throughout the colony to let the other bees know the queen is alive and well. If this substance gets weak or disappears the bees know that a queen is not present and will respond by swarming or producing a new queen.
Each colony also has a distinct smell, the Nasonov pheromone produced by the worker bees fanning the hive. This is the sweet smell of home, at least for a bee.
A more complete list of bee pheromones is available on this Wikipedia page.
Like other systems, individual bees have an excretory system to eliminate waste. Bees will not eliminate waste within the hive, though, and even in winter will wait for a warm day to fly outside the hive and dump their loads.
As a superorganism, worker bees move about the hive to locate foreign objects such as small twigs, moth larva, dead bees and other unwanted substances. These are dumped outside the hive to keep the interior clean and fresh.
This system is actually quite sophisticated in colonies. Aside from the meticulous cleaning of the hive, bees produce propolis made from tree sap and other plant substances. Propolis is a sticky substance with antibiotic and antifungal properties. The bees seal every crack smaller than a bee with it to protect the hive from intruders, and they coat foreign objects with propolis to keep it from harming the hive. A mouse entering an active hive may be stung to death and covered in propolis; this propolis layer keeps the dead mouse from rotting so it dries out within the hive. Internal combs where eggs are laid are also treated with propolis to sanitize cells for each new generation.
For external intruders, of course, worker bees are equipped with a stinger to vigorously protect the hive. A dead bee, whether from stinging or squishing, releases an alarm pheromone that alerts other bees of a potential danger to the hive. Beekeepers and other large creatures are particularly susceptible to a build-up of alarm pheromone that can result in more stings if they hang around a hive too long.
The skin and its appendages, whether hair, feathers, or scales, form the integumentary system in animals. This maintains the internal conditions for life, and reduces the ability of external factors such as water and heat to interfere with the body.
For a honey bee colony, the external hive serves part of this function. Small cracks and holes in the hive are filled with propolis to complete the external protection. Bees will even move into a hive box full of holes or with a leaky roof, knowing they can seal it up from the inside.
Muscles in a body are required to move a person throughout the world. For a beehive, bees serves as the eyes and ears of the colony, so to speak. A muscular system, therefore, is not required.
Like muscles, the beehive does not need electronic signals passing around the colony. I imagine the bees would not enjoy this at all. Instead, bees signal each other with their antennas and with chemical pheromones to transfer information around the colony.
Beehives reproduce by swarming, of course, quite different but just as effective as sexual reproduction. When a hive is of sufficiently crowded, the workers in the hive will raise a new queen, and the existing queen will leave with the older bees to find a new home. How bees swarm and choose their new nest is the subject of the aforementioned book Honeybee Democracy by Thomas D Seeley.
According to the book, swarms prefer to find a nest that is roughly 15 feet off the ground, 40 liters in volume, with a small entrance facing south near the bottom of the cavity.
Individual bees breath, as you would expect. A colony also breaths in it’s own way. During the summer, worker bees fan their wings to circulate air throughout the hive, regulating temperature and evaporating honey. This thermoregulation, as it is called, maintains the temperature in the brood nest at roughly 95° F (35° C) which is the optimal temperature for raising young bees. In the winter, the bees cluster together for warmth, using their flight muscles to generate heat. The cluster expands and contracts as necessary to keep warm.
In a swarm, bees using the same techniques to keep the swarm cluster cool. In addition to expanding and contracting the cluster, worker bees will establish channels of air flowing through the cluster to maintain the internal temperature.
Our final system is the skeleton. Once again individual bees have an exoskeleton, as do most insects. For the colony, I think the honeycomb provides the “bones” of the hive.
So there you have it. A honey bee colony as a superorganism, with similar support systems that you and I enjoy in our very own bodies.
I suspect bees, and especially bee colonies, do not suffer existential thoughts as Hamlet does in Shakespeare’s The Tragedy of Hamlet, Prince of Denmark. Hamlet utters the famous “To be or not to be” line while contemplating life and death. Bees seem rather focused on their day to day life and are perfectly willing to sacrifice themselves for the good of the larger colony.
I almost used this title for my very first post, representing the idea of being or not being a beekeeper. I eventually decided the alphabet theme of A Bee Sees would be a better starting point for this journey. I have been waiting for a good subject for Hamlet’s line, and the idea that bee colonies might be superorganisms seemed appropriate.