Tag: swarms

The Science of a Murmuration of Starlings

Posted on | by Sam

What words can do justice to the magic of a million birds, flying and weaving as one? Improvisatory choreography? Elegant chaos? Symphonic cacophony?

There is no familiar way to make sense of this natural phenomenon — both what starlings do and how they make us feel when we see them.  Yet the flocking behavior of the birds the ancient Romans believed foretold the will of the Gods — indeed, the word auspicious comes from the Latin auspicium, or “divination by observing the flight of birds” — is a natural manifestation of a set of principles for organizing complex behavior,  and an observable phenomenon that runs counter to the way we human beings have made sense of the world for as long as anyone can remember.

Starlings are native to several continents, although North America is not one of them.  Back in 1890, however, a Shakespeare enthusiast decided that all birds mentioned in Shakespeare’s plays should be brought to North America (the starling makes its star turn in Henry IV, Part 1). His idea worked — a little too well. From an initial group of 100 birds, the starling population in North America now tops 200 million. And it is the behavior of each bird in those massive, undulating flocks that makes the starling so notable — and, for some, so magical. 

Almost a century ago, the British ornithologist Edmund Selous asserted that these “handsome, lively, vivacious birds” were telepathic. Today, the biologist Rupert Sheldrake suggests that starling behavior is an example of his hypothesis of morphic resonance, or the notion that the laws of nature are “more like habits, ones in which each individual inherits a collective memory from past members of the species, and also contributes to the collective memory, affecting other members of the species in the future.” And yet beyond these appreciations and speculations, we have lacked the ability to concretely explain how a murmuration works — how one million individual creatures can dart and soar in self-organizing synchrony . . . until now.

Thanks to the work of two separate studies from 2013, we now know that individual starlings all obey the same few flight rules:

Watch your seven nearest neighbors.

Fly toward each other, but don’t crowd.

And if any of your neighbors turn, turn with them.

Why do they do this? According to one of the studies, “when uncertainty in sensing is present, interacting with six or seven neighbors optimizes the balance between group cohesiveness and individual effort.” 

By following this rule of seven, the birds become part of a dynamic system in which each individual part combines to make a whole with emergent properties. This collective behavior allows the birds to gather information on their surroundings and self-organize toward an ideal density, one in which optimal patterns of light and dark are produced that can deliver information to the entire flock (and protect them from predators). The closer each bird pays attention, the safer — and more cohesive — the entire flock becomes.

Of course, this sort of swarming behavior is not unique to starlings. Many different animals, from birds and insects to fish and mammals, have been observed in their own form of a swarm. So what can this behavior teach us about ourselves, our organizations, and our ability to change the story of the way we work and learn?

According to Andreas Weber, author of The Biology of Wonder, “the spirit of poetic ecology is the spirit of swarms. To understand the individual, we need to understand its environment, and each through the other. We have to think of beings always as interbeings.

“We are a swarm ourselves,” Weber writes, “and we form swarms. A swarm does not have intelligence; it is intelligence. In this respect, a swarm (or a murmuration) is an intensified counterpart of ourselves. It is what we are and what we try to imagine with our conscious thinking. Swarms are solidified feeling. The swarm is — and in its being living dynamics and their expression are welded together in one single gesture.”

In other words, a murmuration is more than just a pretty metaphor for thinking differently about organizational behavior; it’s a reminder, in physical form, that our own bodies, cultures and classrooms are governed by the same rules. As Weber puts it, “we see gestalts of the living that behave according to simple organic laws mirroring the great constellation that every living being has to cope with: to persist, to be close to the other, but not so close as to collide with him. These are the principles of poetic forms that are so thorough we can even teach them to a computer. They are the primary shapes of a poetics of living things.”

The Science of Honeybee Democracy

Posted on | by Sam

There may be no creature on earth more vital to our own well-being than the honeybee — the primary pollinator for fifty different fruit and vegetable crops that make up the most nutritious portion of our daily diet.

Less debatable, however, is whether this same bee is also the ideal model for our ongoing efforts to craft a more perfect union — or at least Shakespeare thought so, when he described honeybees as the “creatures that by a rule in nature teach the act of order to a peopled kingdom.”  

But why? And how?

According to the American biologist Thomas Seeley, it’s because of the ways honeybees relate to one another — clearly, constructively, and collaboratively. “The process of evolution operating over millions of years,” he explains, “has shaped the behavior of bees so that they coalesce into a single collective intelligence. Just as a human body functions as a single integrated unit even though it is a multitude of cells, the superorganism of a honeybee colony operates as a single coherent whole even though it is a multitude of bees.”

Although there are many examples of this in honeybee behavior, the most illustrative occurs every year in late spring and early summer, when a beehive is most likely to get overpopulated. When this occurs, roughly one-third of the hive’s bees promptly elect to stay and rear a new queen — who will ultimately be chosen, no holds barred, from the current queen’s few surviving daughters — while the remaining two-thirds politely accept their eviction notices and leave with the old queen to set out into the great unknown and create a new colony.

When they depart, as many as 10,000 honeybees can form a swarm cloud as large as 60 feet across. Yet within minutes, the bees will quickly reassemble somewhere into a beard-shaped cluster, and then hang that way for the next several hours or days, awaiting word, while several hundred of the swarm’s oldest citizens spring into action as nest-site scouts and begin exploring a swath of the surrounding countryside — as large as 30 square miles — for a suitable new home. 

This is, to be clear, a life or death decision. 

To survive in winter, a hive must be able to contract itself into a tight, well-insulated cluster — about the size of a basketball. They must find a home that is high enough to avoid detection by hungry predators. And they must have space for the copious amounts of provisions — i.e., honey, as much as 44 pounds of it — that will have to sustain them until Spring. 

Despite these stakes, the swarm will make this decision within hours, and from as many as 30 different possible nest sites.  And they will do all of this democratically, without any central leader. Indeed, despite her name, the Queen Bee is not the boss of anyone, and a honeybee hive is governed collectively — a harmonious society of hexagonal cells wherein thousands of worker bees, “through enlightened self-interest, cooperate to serve a colony’s common good.” 

In a swarm, this happens when the nest scouts all set out in different directions in search of the perfect new home. When they think they’ve found one, they return to the group and offer a sort of “waggle dance,” a series of movements that outline the central characteristics of the proposed site, and invite other bees who agree on its merits to join them in waggle-dancing.

This continues as more and more scouts return, and gradually, a face-to-face, consensus-seeking assembly takes place in which an eventual winner is democratically determined. “One way to think of a honeybee colony, then, is as a society of many thousands of individuals,” Seeley explains. “But to understand the distinctive biology of this species of bee, it is often helpful to think of a colony in a slightly different way, not just as thousands of separate bees but also as a single living entity that functions as a unified whole.”

In that sense, the collective decision making of a bee swarm resembles an archetypal New England town meeting, one in which each decision reflects the freely given contributions of several hundred individuals; is informed by multiple sources simultaneously, even ones that are widely scattered; and is made by staging an open competition among the proposed alternatives. “In this way, Seeley continues, “the roughly three pounds of bees in a swarm, just like the three pounds of neurons in a human brain, achieve their collective wisdom by organizing themselves in such a way that even though each individual has limited information and limited intelligence, the group as a whole makes first-rate collective decisions.”

(Y)our move, homo sapiens . . .