Tuesday, March 5, 2013

The Busy Bee Brain

With brains in the news these days (for example, all the hoopla about the Brain Activity Map project) I've decided to republish this old post suggesting that the brain is like a swarm of bees in your skull.

Ordering Mark Moffett’s Adventures Among Ants got me to thinking about a science fiction novel that knocked my socks off when I was 12 or 13: Man of Many Minds, by E. Everett Evans. It’s about George Hanlon, a man who had the ability to project his mind into other creatures. At a critical point in the book, when – I believe – Hanlon is about to be tortured, he projects his whole mind, every last bit of it, into a swarm of bees, thereby escaping the pain of torture.

I thought that was pretty neat.

But what does it have to do with Moffett’s book? That’s pretty simple. Ants, like bees, live in groups, and it’s not unusual to think of such groups as being some kind of superorganism – a notion that, according to this blog entry, Moffett subjects to a critical workout. That swarm of bees in Man of Many Minds is such a superorganism.

But when it “absorbed” Hanlon’s mind, what did it become then? The question is a rhetorical one; after all, it’s about something never really happened. It’s just fiction. But a very suggestive fiction.

Could the human brain be something like a hive of bees?


There is now a pretty strong consensus that the cerebral cortex (which is, by no means, the entire brain, but it is likely that this is where culture is carried) is organized into small columns of neurons. In a 1978 essay Vernon Mountcastle called these minicolumns and suggested that they have about 100-300 neurons each. He estimated that the neocortex consists of 600,000,000 of these minicolumns. He also suggested that these minicolumns are organized into macrocolumns, about 600,000 of them -- implying that there are hundreds of minicolumns per macrocolumn. (Mountcastle was clear that these numbers were just order of magnitude estimates & that is all I need for my purposes.) That makes these macrocolumns roughly the size of a typical invertebrate nervous system of 10K to 100K neurons. So, here’s my metaphor: Your neocortex consists of 600,000 buzzing bees going about their business.

The point of the metaphor is that, just as individual bees are autonomous agents (which must, nonetheless, feed and reproduce in a group), so the macrocolumns are autonomous agents (which are physically coupled to many other such agents). Bees go about their business by sensing optical and chemical gradients and features and by moving their bodies and excreting chemicals. The macrocolumns are not directly connected to the external world, but they have extensive inputs and outputs to other macrocolumns and to other regions of the brain and nervous system. From a purely information processing point of view, they are as capable of action as are bees. They “sense” neurochemical gradients in the intersynaptic space and act on their sensations by excreting chemicals into that space.

This loose metaphor really gets interesting, however, when we begin to think about human interaction, which of course implies interaction between brains. Some interactions are pretty loose, such as those between people strolling the aisles at a supermarket. Other interactions are tighter, such as people having a conversation over a meal. And some interactions are very tight, such as musicians making music with one another. And that brings us back to insects, fireflies in particular.

Allow me to quote a passage from Chapter 3 of Beethoven’s Anvil:
Physicists do understand one element of dance, simple repetitive rhythm. This understanding has been applied to many biological systems, one of which is male fireflies in Southeast Asia. These fireflies gather in large groups on river banks, flashing on and off in unison to signal their availability to females. When they begin gathering around sunset their flashings are uncoordinated. But, as dusk darkens into night, regions of synchronized flashing emerge and spread until whole trees are cloaked in fireflies flashing in synchrony.
That is to say, in some sense, the nervous systems of those flies have become temporarily coupled together into a single physical system where some some signals are transmitted within nervous systems through electro-chemical means while other signals are transmitted from one nervous system to another by energy transduction (sending: chemicals → photons, and receiving: photons → chemicals) and light (i.e. photons). I go on to say:
There is no reason to believe that this activity is directed in the way that a conductor directs an orchestra. There is no lead firefly setting the pace of the others. The flashing simply emerges; it is self-organized. Each firefly is making his own decisions about when he’ll flash, influenced by the activities of his neighbors. This activity has been analyzed as a system of coupled oscillators, a phenomenon first noticed by the seventeenth century Dutch physicist Christiaan Huygens, who invented the pendulum clock—the pendulum being a prime example of an oscillator. One day Huygens saw that the pendulums of two clocks on the same wall were swinging in perfect synchrony. He disturbed one of them so that the synchrony dissolved, but it returned within half an hour. After a bit of experimentation he concluded that the clocks were affected by the vibrations each transmitted to the wall behind them. These vibrations led them to synchronize their periods and thereby minimize their collective energy expenditure.

Any phenomenon common to systems as different as pendulum clocks and fireflies must be very general.
I then go on to develop an argument that music works like that as well. As I say in my review of Steven Mithen’s The Singing Neanderthals, “what musicking does is bring all participants into a temporal framework where the physical actions - whether dance or vocalization - of different individuals are synchronized on the same time scale as that of neural impulses, that of milliseconds. Within that shared intentional framework the group can develop and refine its culture. Everyone cooperates to create sounds and movements they hold in common.” While making music, I argue, we may consider the nervous systems of individuals as being physically coupled together so as to constitute a single dynamical system that is distributed across separate individuals. When the music-making stops, the distributed system dissolves into its individual components; individuals, that is to say, their brains, are free once again to operate independently of one another.

The point of this exercise is that, by (the reductive step of) insisting on thinking of brains as physical systems, and therefore insisting that interactions between brains is physical interaction, we can arrive at a concept of a very special human group – one engaged in music-making – as a single distributed nervous system. That is possible only because the fundamental coupling requirements are very simple, simple enough that fireflies and neurons can meet those requirements.

If fireflies can teach us about how we can make music, than surely ants have much to teach us as well. I look forward to reading Moffett’s book.


If you're at all curious about what a bee brain might actually be like, well Nature Precedings has something similar, an account of the brain of the fruit fly.

David J. Osumi-Sutherland1, Mark Longair & J. Douglas Armstrong


Drosophila neuro-anatomical data is scattered across a large, diverse literature dating back over 75 years and a growing number of community databases. Lack of a standardized nomenclature for neuro-anatomy makes comparison and searching this growing data-set extremely arduous.

A recent standardization effort (BrainName; Manuscript in preparation) has produced a segmented, 3D model of the Drosophila brain annotated with a controlled vocabulary. We are formalizing these developments to produce a web-based ontology-linked atlas in which gross brain anatomy is defined, in part, by labeled volumes in a standard reference brain.

We have developed new relations that allow us to use this well-defined gross anatomy as a substrate to define neuronal types according to where they fasciculate and innervate as well as to record the neurotransmitters they release, their lineage and functions. The resulting ontology will provide a vocabulary for annotation and a means for integrative queries of neurobiological data.

The ontology and associated images, queries and annotations will be integrated into the Virtual Fly Brain website. This will provide a resource that biologists can use to browse annotated images of Drosophila neuro-anatomy and to get answers to questions about that anatomy and related data, without any need for ontology expertise.


  1. The interesting thing is that a large ant society can weigh as much or more as an adult Homo sapiens, and contain a greater number of nerve cells than our brains. In fact I argue in Adventures Among Ants that an ant colony is the insect way of making a large organism--but with the flexibility of being distributed across space in ways impossible for us, and incapable of being killed with a single bullet to the heart or brain (because hearts and brains are also dispersed among many individuals). So when people ask me why there are no ants as huge as the ones in old science fiction movies, I respond "who says there aren't?"

  2. Do we know whether or not ant neuropil is as energy intensive as human neuropil? I believe that the human brain consumes 20% of our energy while only being roughly 3% of body weight.

  3. Ants, being cold blooded, consume less energy, including in their nervious systems. So the fair comparison at the colony level might be a large reptile rather than a human!

  4. What about the ratio of energy consumption, neuropil-energy to the total energy consumption? Though I certainly don't know this, I'm supposing that the energy consumption per cubic ml is the same for human neuropil as it is for, say, macaque neuropil or, for that matter, lab rat neuropil. What's special about humans is the relatively large body volume given over to neuopil. Do we know whether invertebrate neuropil uses energy at the same rate? And . . . it's a really complicated question. Energy usage will dependent on what's being done and local temperature at the tine, yadda.

    So we've got the ant colony as a Komodo dragon.