After a couple of rewrites, I think I’ve found that the most logical way to structure this is to first overview the very basics of an individual honeybee’s biology. I’ll hold off until my next post to zoom a bit out in scope, and do a relatively similar analysis with the entire colony. Even though what I really want to talk about is how honeybees work together, I’ve found that without a really concise examination of the pieces, it’s hard to appreciate the entire puzzle.
(Also, important side note: I’m going to limit my analysis to a single species of honeybee, Apis mellifera, as it is the most common bee used in beekeeping, as well as the most widely disseminated. It is native to the whole of Africa, Europe, the Middle East, and was introduced to both the Americas in the 1600’s.)
Alright, let’s ignore for a moment the social aspect of honeybees, and talk about the honeybee as a single creature. I think this is important because before we can discuss (and really even appreciate) the colony as a whole, there is a whole lot to understand about the anatomy, castes, and jobs that are unique to honeybees as a species.
Anatomy: Baby Got Thorax
I’ll be basing this off of the diagram that Irene at http://quatremilliards.tumblr.com/ drew for me. It’s of a female ‘worker’ bee, (I’ll go over the different types of bees later, but the colony consists almost entirely of worker bees who are in charge of all the non-reproductive tasks of the hive) and it’s probably best to keep referencing the diagram.
For centuries biologists have marveled at the peculiar ability of honeybees to ‘get a lot of different shit done really goddamn fast’. And while this may not exactly be how they would have phrased their admiration, there is really no doubt that the individual bee is a seriously industrious motherfucker. It is no surprise then that its anatomy reflects this fact. Highly tweaked and tuned, a honeybee has many unique physical features that allow it to specialize in any one of dozens of different tasks it may be required to undertake. I’ll sub-categorize these features, but note that this is by no means a complete list, just what I think is relevant.
- Foraging Features: Honeybees are fairly well adapted at carrying their food and water long distances back to their hive. Their stomachs are sectioned off into a crop (where they store water or nectar for travel, like a horribly creepy pocket) and a midgut, where the actual digestion starts. Honeybees have control over whether or not what they swallow makes it past the crop, and are also able to regurgitate the food stored in their crop on a whim, which makes a fascinating party trick I have yet to master. For carrying pollen they use a different tactic: They wet down the pollen with their saliva, and pack it firmly onto the hairs on their rear legs, where it is securely clustered in a ball.
- Heating Features: Honeybees are remarkably good at creating heat, which is actually an exceptionally important aspect of their biology. What they do is isometrically flex (read: shiver) their wing muscles really rapidly, which produces a surprising amount of heat. This both warms them to a point where they are able to fly (bees can’t fly if they are internally cooler than 35 degrees Centigrade) and is also used to raise the temperature of the hive (the hive needs to maintain a very specific internal temperature for a bunch of reasons I’ll get on that later).
- Communicative Features: Honeybees have a special gland called the Nasanov’s gland that produces a strong and strangely citrus-scented pheromone (think ‘lemon pledge’ meets farting). This pheromone helps lead other bees to scentless areas (such as bodies of water), and marks the entrance of the hive so amature foragers can find their way back home. Side note: Some of the most important communication done by honeybees is mainly behavioral and not very easily ascertained by focusing on their anatomy. I’ll spend a large time focusing on this in my next blog, but bees mostly communicate through seemingly innocuous interactions and, I kid you not, interpretive dance. Yes, you read that correctly.
- Hive Building Features: Fun fact: All insects coat their exoskeleton with a thin layer of wax to keep them from drying out. It’s this reason why bugs look so shiny, and perhaps also why they taste so horrible. Honeybees have adapted this wax-making ability with their wax glands, to produce excess wax when they need it. They chew, heat, and mold this wax to create their comb and hive, though they mix it with a tree resin they collect called propolis (which has both anti-fungal properties and adds structural stability to the comb).
- Feeding Features: Bees eat three types of food: Honey (which is a mixture of nectar and their saliva), pollen, and a substance known as ‘royal jelly’. Royal jelly is a very protein- and hormone-rich secretion produced in the hypopharyngeal gland, which is located in the honeybee’s head. So yeah, bees occasionally eat one another’s head juices, although in highly regulated amounts. This stuff is also very important to the bee’s caste system, because eating large amounts of royal jelly in the larval and pupal stage of a bee’s development will turn a normal worker bee into a fabulous queen bee.
- Hurty-Stingy Features: Sterile worker bees have adapted ovipositors (egg laying organs) called stings with which they use to attack their enemies (bears, competing hives, rodents, the 13-year-old me that for god knows what reason thought it was a good idea to throw his shoes at a bee hive). This sting is coated with venom from its venom sac, and if you ask the thoroughly retarded 13-year-old me, that stuff hurts.
The Caste System: Workers, Drones, and fabulous, fabulous Queens
Gender, one of the cruxes of the honeybee caste system, means something completely different for bees than it does for humans. All fertilized eggs produce genetically female bees. These bees, depending on how they are fed during their larval and pupal stage, will then either go on to become sterile worker bees, or far less commonly, queen bees. It is unfertilized eggs (which therefore share 100% of their genetic material with their mother) that become male, or drone, honeybees. Let’s do a fairly brief overview of this.
- Drone bees: Queen bees can decide, although only during the warm summer months (mating season), to lay a very small percent of their eggs unfertilized. These unfertilized eggs hatch into horndog male drone bees, whose sole focus is on finding and having sex with un-mated virgin queens from other hives. If they’re lucky, and often they aren’t, they’ll have sex once and then immediately die. They do this and… actually that’s it, it’s all they do. They literally serve no other purpose than to fly around hunting for tail. And, in the ultimate bachelor move, they do not even feed themselves. This is actually kind of funny, because when the rest of the colony decides the drones have served their purpose, the colony will simply stop feeding them, and they all die. Ha?
- Queen bees: If the old queen dies (or is rendered ‘unfit’), or if the colony is sufficiently large, it will decide as a whole to rear new queen bees. This happens very infrequently, only every one to three years if the old queen is still alive, or immediately if she dies. How the colony rears new queens is by feeding a few (usually three to five) of the newborn female bees a very large amount of royal jelly (the face juice we talked about). Because of the high hormone content of this diet, the pupa and larvae of these soon-to-be queen bees will develop much differently than the otherwise normal worker bees. If the old queen was still alive when the colony started to produce new queens, she will fly off (before the new queens hatch) with two-thirds of the workers and start a new hive. Normally, the first of the queen bees to hatch will attempt to kill off the others and claim the hive for her own, but in cases where the colony is really, really large, she’ll do the same as the old queen and take another fraction of the workers to leave and found another new colony. The next queen to hatch then kills all the others queens and claims the hive for her own. After this whole escapade, the new queen will leave on her only mating flight, where she does it with eight to ten dudes from other colonies. When she comes back, she’s loaded with enough semen for her entire life. And, for the rest of her life, that’s all she does, use this semen to pump out thousands of babies. Side note: The queen, despite her regal name, has absolutely no level of control over the other bees, and is merely pushed around all day as she lays eggs. If, in fact, she at any time becomes injured or is deemed unfit to continue having children, the other bees will simply ignore her completely, and she will die of starvation as she watches the hive breed her replacement. Pretty cold, huh?
- Worker Bees: These are the backbone of the entire bee economy and workforce. Because they are in charge of and do everything non-reproductive in the hive, they’re pretty much what I’ll be talking about for the entire rest of my blog. Because of this, I’ll move straight into the different jobs a honeybee has during its lifetime, because I’m essentially only referencing the worker bees.
Various Jobs: Odd, Hand, and Others
So, to finish up this blog, let me do a very brief overview of the different areas where a colony has to allocate its workforce. I’d to take this moment to note that honeybees have an extremely strong correlation between their age and their current vocation. For example, usually only the oldest of the bees will engage in foraging, and usually only the youngest will engage in taking care of the brood (larvae and pupae). This though, is flexible, and in the case of a sudden and large extermination of the workforce*, the colony will regulate itself back into proper homeostasis.
So, at any given point, a single honeybee may be engaged in one of these various different activities. How these jobs are efficiently allocated though, I will leave to explain in future posts. For now I just want to give a feeling for the vast range of jobs a single bee may undertake. Here is only a partial list of what a honeybee may be required to do:
- Clean out the old cells of the honeycomb for new eggs or honey and pollen storage.
- Take care of and feed the brood (larvae and pupae honeybees that are still confined in cells).
- Tend and clean the queen bee.
- Feed and groom fellow nest-mate bees.
- Keep the brood area of the comb constantly between 33 and 36 degrees Celsius (cool and heat).
- Build and shape more of the comb.
- Forage for nectar, pollen, water, and tree sap (this is a huge one).
- Inform other bees about nectar and pollen forage sites.
- Patrol and guard the hive.
- Store nectar and pollen in the comb.
- Lay eggs (this one is for the queen only).
- Be fabulous (this one is for queens as well, but may extend beyond bees).
And this is only a partial list. Even still, it’s quite obvious that much like a man reading dirty magazines at the office, these little honeybees are definitely hard at work. But what this list doesn’t fully explain is how precisely these jobs are allocated. Somehow the bees seem to never extend more resources than are required, and maintain a constant balance between deciding which workers should be doing each activity. The level of efficiency in this allocation is absolutely mind-blowing, as is the fact that it’s done completely without a centralized intelligence.
If I’ve done my work, this should lead you to ask some questions, chiefly: Well how the hell do they do that?
And that’s a damn good question.
* See Tom Seeley’s book: The Researcher’s Baseball Bat; How Bees Maintain A Balance Even In The Face of My Iron-Armed Adversity.