Sex on Six Legs_ Lessons on Life, Love, and Language From the Insect World - Marlene Zuk [92]
Consensus decisions are distinguished from what are called combined decisions because they require everyone to concur, which means the group has to possess a fairly sophisticated means for exchanging information. A combined decision is made when the individuals in a group simply assign themselves different tasks, for example, the allocation of hive cleaning versus foraging in bees, but don't all agree beforehand on a list of who will do what. The distinction is important because getting everyone to agree to a single outcome means that they may have to sacrifice their own interests in doing so, a rather advanced capacity for a tiny insect. Many scientists first started thinking about the possibility of a "hive mind," that controversial greater-than-the-sum-of-its-parts superorganism, when pondering the way that social insects choose a new place to live.
Aristotle had noticed that it seemed as if bees received information from scouts that had made advance sallies to find potential nest sites, but the process of deciding on a new nest site was first studied in detail in the 1950s by a German zoologist, Martin Lindauer. He happened upon a swarm near the Zoological Institute at his university in Munich and noticed that a few of the bees on the outside of the swarm were performing the same waggle dance that his mentor, the Nobel laureate Karl von Frisch, had described in the context of signaling the whereabouts of food sources. Since the bees had no pollen or nectar, Lindauer wondered if they might be signaling not the location of a patch of flowers, but the possible place the swarm might settle.
By recording the different locations encoded in the dances of the apparent scouts, Lindauer noticed that although the bees seemed to be dancing "for" many different sites at first, eventually they seemed to settle on just one. Soon after this winnowing of alternatives, the swarm rose in a body and took off for the site that had made it to the finals. In the decades that followed Lindauer's work, scientists established the characteristics that bees would use in their description of a dream house to a bee real estate agent, including a south-facing entrance, a small enough entrance hole to discourage unwanted visitors, and enough room for an average-sized honeybee colony to spread out in comfort. The ability to compare several different possibilities, like enterprising couples scanning the online real estate ads, indicates a rather sophisticated cognitive ability on the part of the insects and has even led to the suggestion that the bees possess some form of consciousness. Why being able to choose a split-level ranch over a refurbished Victorian is peculiarly emblematic of higher intelligence, while other decisions are not, is unclear to me, but it is undoubtedly a complicated decision.
In the 1990s, Kirk and his former advisor, the eminent bee expert Tom Seeley at Cornell University, began to work with other colleagues to determine how the selection of just one site was made. One swarm took about 16 hours of dancing, spread over three days, to reach a decision, with eleven different potential sites taken under consideration before the winner was determined. In a New York Times column, James Gorman noted that the scientists were, like Maeterlinck, convinced that the bees arrived at decisions that were good for the group, and that "Dr. Seeley is a bit more cheery than Nietzsche," a comparison that was probably novel for both the entomologist and the philosopher.
So how do the bees choose the winner? The idea of a bee version of polling the hive constituents