Honeybee Democracy

Honeybee Democracy by Thomas D. Seeley

Princeton, NJ:  Princeton Univ Press, 2010

ISBN 978-0-691-14721-5

(5)  So the mother queen is not the workers' boss.  Indeed, there is no all-knowing central planner supervising the thousands and thousands of worker bees in a colony.  The work of a hive is instead governed collectively by the workers themselves, each one an alert individual making tours of inspection looking for things to do and acting on her own to serve the community.

(11)  The duration of the waggle run - made conspicuous despite the darkness by the dancer audibly buzzing her wings while waggling her body - is directly proportional to the length of the outward journey.  On average, one second of the combined body-waggling/wing-buzzing represents some 1,000 meters (six-tenths of a mile) of flight.  And the angle of the waggle run, relative to straight up on the vertical comb, represents the angle of the outward journey relative to the direction of the sun.  

(35)  In the mid-1970s, for three years I followed the fates of several dozen feral honeybee colonies living in trees and houses around Ithaca, and I found that less than 25 percent of the "founder" colonies (ones newly started by swarms) would be alive the following spring.  In contrast, almost 80 percent of the "established" colonies (ones already in residence for at least a year) would survive winter, no doubt because they hadn't had to start from scratch the previous summer.  Beekeepers describe the time and energy crunch faced by swarms in a rather grim, three-line rhyme:  "A swarm of bees in May is worth a load of hay, a swarm of bees in June is worth a silver spoon, a swarm in July isn't worth a fly."

(54)  The bees had revealed to me that they prefer a nest entrance that is rather small, faces south, is high off the ground, and opens into the bottom of the nest cavity.

(75)  But it is always a "friendly" competition;  the scout bees agree on what makes an ideal homesite, they are united in the goal of choosing the best available site, they share their information with full honesty, and ultimately they reach a complete agreement about their new residence.  One valuable lesson that we can learn from the bees is that holding an open and fair competition of ideas is a smart solution to the problem of making a decision based on a pool of information dispersed across a group of individuals.

(86)  This is a different sort of collective choice, for whereas a homeless swarm makes a "consensus decision" about which _single options_ (candidate nest site) it will choose, a foraging colony makes a "combined decision" about how to allocate its foragers among _multiple options_ (candidate food sources).

(91)  Main features of bees' decision-making process:

First, they showed that the bees' debates tend to start slowly with an information accumulation phase during which scout bees put a sizable number of widely scattered alternatives "on the table" for discussion. 

(92)  Second, the plots of the dance records showed that the shout bees' debates end with all or nearly all of the dancing bees advocating just one site, that is, showing a consensus....

Third, our analysis showed that the bees' decision-making process is a highly distributed and thus a democratic one, involving dozens or hundreds of individuals.

(95)  These findings support the idea that scouts come largely, if not entirely, form the ranks of a colony's foragers.  Both scouts and foragers make long-distance excursions from a central location (swarm or hive) and then must find their way home, so it is easy to imagine that bees with foraging experience make the best scouts.

(98)  I find it extremely suggestive that Lindauer started seeing some of his labeled foragers exploring his nest sites, not exploiting his feeder, a few days after he started noticing most of his previously active foragers sitting around idly, either in some quiet spot outside the hive or in the "beard" of bees hanging outside the entrance.  Anecdotal observations like these are the perfect springboard for an experimental investigation designed to test conclusively whether it is a persistently full stomach per se, or something else associated with forced indolence, that informs foragers to become scouts.

(101)  Given that humans and other animals usually make decisions by drawing on a toolbox of heuristics, it is remarkable that a honeybee swarm does not use these shortcut methods of decision making and instead selects its new living quarters by taking a broad and deep look at the bee housing market.  As we have seen in chapter 4, a swarm makes its decision only after its scout bees have discovered numerous alternative nest sites and have performed a multifaceted inspection of each size...  And as we have seen in chapter 3, each candidate site is evaluated with respect to at least six attributes (e.g., cavity volume, entrance height, and entrance size).  Thus a honeybee swarm pursues an unusually sophisticated strategy of decision making, one that involves nearly all of the information relevant to the problem of choosing the best place to build its new nest...  A swarm is able to be so thorough in choosing its home because its democratic organization enables it to harness the power of many individuals working together to perform collectively the two fundamental parts of the decision-making process:  acquiring information about the alternatives and processing this information to make a choice.  We will now look at the evidence that honeybee democracy does indeed achieve nearly optimal decision making.

(123)  In short, the richer the nectar source, the stronger the waggle dance.  We had also figured out how a dancing bee adjusts the number of dance circuits that she produces in relation to nectar-source richness.  She does so by adjusting two aspects of her dancing:  the _rate_ of dance circuit production (R, in dance circuits per second) and the _duration_ of dance circuit produced (C, in dance circuits) in a dancing bee's advertisement is the product of the rate and duration of her dancing (C=R x D).  So, richer nectar sources elicit livelier (higher R) and longer-lasting (greater D) dances than do poorer nectar sources.  

(140-142)  One strong possibility is that the bees were driven to retire from advertising the losing sites by an internal, neurophysiological process that causes every scout to gradually and automatically lose her motivation to dance for a site, even one that is high in quality.  Such a process would foster consensus building among the scouts, for automatic fading of each bee's dancing would prevent the decision making from coming to a standstill with groups of unyielding dancers deadlocked over two or more sites.  It might also help the dancers reach unanimity more quickly than they would otherwise, for endowing each bee with an automatic tendency to lose interest in any given site would make each bee a highly flexible participant in the decision-making process.

(143)  The drop in dance strength per trip (about 15 dance circuits) appears to be a constant, regardless of series length.

NB:  Town meeting rules by which one member can't speak a second time on an issue until everyone else who wishes to be heard has a chance to speak.

(144)  Both bees and humans need a group's members to avoid stubbornly supporting their first view, but whereas we humans will usually (and sensibly) give up on a position only after we have learned of a better one, the bees will stop supporting a position automatically.

(165)  "Ritualization" is the name biologists have given to the process whereby some incidental action of an animal becomes modified over evolutionary time into an intentional signal.

(166)  If the hypothesis of scout bees as mobile temperature sensors, information integrators, and group activators proves correct, then the mechanisms mediating the initiation of takeoffs by honeybee swarms present us with an intriguing system of behavioral control within a large group.  It is one in which a small minority of individuals actively poll the group to collect information about its global state and then, when the group reaches a critical state, these individuals produce a signal that triggers an appropriate action by the whole group.  

(199)  Instead, in both swarms and brains, the decision-making process is broadly diffused among an ensemble of relatively simple information-processing units, each of which possesses only a tiny fraction of the total pool of information used to make a collective judgment.  We will see that natural selection has organized honeybee swarms and primate brains in intriguingly similar ways to build a first-rate decision-making group from a collection of rather poorly informed and cognitively limited individuals.  These similarities point to general principles for building a sophisticated cognitive unit out of far simpler parts.

(203)  First, a sensory transformation converts the information about the external world that has been registered by the animal's sensory organs into a "sensory representation," which makes the information available for further processing within the animal's brain.  This is what the MY neurons do in the monkey's motion-detection task.  Second, a decision transformation converts the sensory representation into a set of probabilities for adopting the alternative courses of action.  In the monkey's brain, this transformation is implemented by the LIP neurons, as they convert the sensory representation of visual motion into a set of "evidence accumulations," specifically the set of firing rates of the integrators representing different motion directions.  The level of firing in a particular integrator population determines the animal's relative probability of choosing the alternative represented by this population.  Third, an "action transformation" converts this set of probabilities into a specific behavioral act.  This final process of action implementation is performed in the monkey's brains by motor neurons in the FEF and SC regions when they are activated by the population of LIP neurons whose firing rates have reached a threshold level.

(210)  Indeed, another shared design feature of the integrators in monkey brains and honeybee swarms is that they are leaky.  In other words, in both systems, the accumulation of evidence in any given integrator declines unless additional evidence flows into it.

NB:  In bees and synapses "zombie lies" die out

(214)  This design [in brains and swarms] has five critical elements:

1.  A population of sensory units (S) that provides input about the alternatives.  Each sensor reports (noisily) on just one alternative, and each sensor's strength is proportional to the quality of its alternative.

2.  A population of integrator units (I) that integrate the sensory information over time and over sensory units.  Each integrator accumulates evidence in support of just one alternative.

3.  Mutual inhibition among the integrators, so the growth in evidence in one suppresses with increasing strength the growth of evidence in the others.

4.  Leakage of the integrators, so the growth of evidence in an integrator requires sustained input of sensory evidence supporting its alternative.

5.  Threshold sensing by the integrators, such that the decision falls to the alternative whose integrator first accumulates a threshold level of evidence.

(220)  Lesson 1:  Compose the decision-making group of individuals with shared interests and mutual respect

(221)  Lesson 2:  Minimize the leader's influence on the group's thinking

(224)  Lesson 3:  Seek diverse solutions to the problem

(226)  Lesson 4:  Aggregate the group's knowledge through debate

(227)  No scout bee, not even one that has encountered a wildly exuberant dancer, will blindly follow another scout's opinion by dancing for a site she has not inspected.

(228)  How can humans use what the bees have demonstrated about aggregating the knowledge and opinions of a group's members to make good choices for the group as a whole?  I suggest three things.  First, we use the power of an open and fair competition of ideas, in the form of a frank debate, to integrate the information that is dispersed among the group/s members.  Second, we foster good communication within the debating group, recognizing that this is how valuable information that is uncovered by one member will quickly reach the other members.  And third, we recognize that while it is important for a group's members to listen to what everyone else is saying, it is essential that they listen critically, form their own opinions about the options being discussed, and register their views independently.

(230)  Lesson 5:  Use quorum responses for cohesion, accuracy, and speed

(231)  E pluribus unum through quorum responses?  Yes, but do so carefully, using a quorum that is sufficiently large to ensure accurate decision making by the community.

(234)  Thus, the house-hunting bees remind us that the leader in a democratic group serves mainly to shape the process, not the product, of the group's deliberations.  The bees also demonstrate that a democratic group can function perfectly well without a leader if the group's members agree on the problems they face and on the protocol they will use to make their decisions.

(236)  The election's outcome is biased strongly in favor of the best site because this site's supporters will produce the strongest dance advertisements and so will gain converts the most rapidly, and because the best site's supporters will revert to neutral-voter status the most slowly.  Ultimately, the bees supporting one of the sites - usually the best one - dominate the competition so completely that every scout bee supports just one site....

Some have said that honeybees are messengers sent by the gods to show us how we ought to live:  in sweetness and in beauty and in peacefulness.

(262)  Frank Bryan, professor of political science at the University of Vermont and world authority on New England town meetings, has taught me much about his specialty and introduced me to Larry Coffin, long-standing moderator of the annual town meeting in Bradford, Vermont...  Michael Mauboussin, chief investment strategist at Legg Mason Capital Management, has showed me the connections between the search comittees of bees and the investment committees of humans and kindly allowed me to borrow from one of his Consilient Observer essays the title for my final chapter, "Swarm Smarts."