Speaker 1: Welcome to BrainStuff, a production of iHeartRadio. Hey, BrainStuff. Lauren
Speaker 1: Vogelbaum here with another classic episode for you. In this one,
Speaker 1: we dive into the startling simplicity behind the complex flight
Speaker 1: displays of groups of starlings. They're so impressive that researchers
Speaker 1: are using them to help power other complicated processes. Hey, BrainStuff.
Speaker 1: Lauren Vogelbaum here. Individually, a European starling is a common blackbird.
Speaker 1: That's it. Starlings are short and thick with dark feathers
Speaker 1: and long pointy bills. If you live in North America
Speaker 1: or Europe, you've seen them, though birdwatchers have spotted them
Speaker 1: throughout most of the world. More than 200 million live
Speaker 1: here in North America alone, singing their chirpy songs and
Speaker 1: being to many backyard growers and full-time farmers a bit
Speaker 1: on the pesty side. Collectively, though, starlings transform into something
Speaker 1: else entirely. Together, in flight, in mesmerizing flocks that sometimes
Speaker 1: number in the hundreds of thousands, they are a breath-stealing wonder,
Speaker 1: a pulsating, swooping, harmonized whole, seemingly defying the laws of
Speaker 1: nature while defining nature itself. To watch a murmuration of
Speaker 1: starlings in midair— that' s what the flocking behavior is called, a
Speaker 1: murmuration— is to experience firsthand the power and mystery of the
Speaker 1: natural world. We spoke with Mario Pessendorfer, a postdoctoral associate
Speaker 1: at the Cornell Lab of Ornithology, who's also a research
Speaker 1: associate at the Smithsonian's Migratory Bird Center. He said, I
Speaker 1: think that the core feeling is a sense of awe.
Speaker 1: The spatial scale of something that's moving very rapidly, which
Speaker 1: we are utterly unable to do, and the visual patterning
Speaker 1: that occurs when a lot of individuals are doing the
Speaker 1: same thing really mesmerizes us. Memorations spark curiosity. And they
Speaker 1: spark scientists like Pessendorfer to figure out how swarming animals,
Speaker 1: like bees and birds and fish, can better our own lives.
Speaker 1: In the 1930s, famed ornithologist Edmund Sellis suggested that birds
Speaker 1: moving in murmurations were using some sort of telepathy to
Speaker 1: transmit their flying intentions. He wrote in his book, Thought
Speaker 1: Transference or What in Birds, they must think collectively all
Speaker 1: at the same time, a flash out of so many brains.
Speaker 1: As the years wore on, we found out that that's
Speaker 1: not quite it. In the 1950s, scientists studying insects and
Speaker 1: fish and other collective animal behavior posited that group movement
Speaker 1: is more of a stunningly fast response to others in
Speaker 1: the flock or school or swarm rather than some innate
Speaker 1: mind-reading ability or a command from a group leader. The
Speaker 1: authors of a 2015 paper published in the journal Proceedings
Speaker 1: of the National Academy of Sciences wrote, It's the rapid
Speaker 1: transmission of local behavior response to neighbors that enables such
Speaker 1: startling synchronicity. Piesendorfer said, there's two ways that you can
Speaker 1: elicit large group behavior. You can have the top-down control
Speaker 1: where you have some kind of leadership or some kind
Speaker 1: of top-down mechanism. Think of a rock show. You have
Speaker 1: the rock star in the front and he starts clapping
Speaker 1: his hands and the whole stadium starts clapping. But these
Speaker 1: murmurations are actually self-organized, meaning that it's the individual's little
Speaker 1: behavioral rules that make it scale up to the large group.
Speaker 1: In order to understand this behavior, we have to go
Speaker 1: from the local scale, what the individual is doing, what
Speaker 1: are the rules that the individual is following, to the
Speaker 1: global scale, what is the outcome? In 2013, a mechanical
Speaker 1: and aerospace engineer and her team from Princeton collaborated with
Speaker 1: physicists in Italy to study murmurations. Naomi Leonard, the Princeton engineer,
Speaker 1: said back then, In a flock with 1,200 birds, it's
Speaker 1: clear that not every bird will be able to keep
Speaker 1: track of the other 1,199 birds. So an important question is,
Speaker 1: who is keeping track of whom? The Italian physicists used
Speaker 1: more than 400 photos from several videos to find out,
Speaker 1: plotting the position and speed of birds as they flocked.
Speaker 1: From that, they built a mathematical model that identified the
Speaker 1: optimal number of flockmates for each bird to track. It
Speaker 1: turns out the magic number is seven. Each bird keeps
Speaker 1: tabs on its seven closest neighbors and ignores all else.
Speaker 1: Considering all these little groups of seven touch on other
Speaker 1: individuals and groups of seven, twists and turns quickly spread,
Speaker 1: and from that a whole murmuration moves. Though it looks
Speaker 1: coordinated on a large scale, the individual birds are concerned
Speaker 1: with only three aspects of their flight and the flight
Speaker 1: of those around them. These factors have been described in
Speaker 1: several ways, but they boil down similarly. They are an
Speaker 1: attraction zone, an area where you're going to move toward
Speaker 1: the next bird over, a repulsion zone, an area where
Speaker 1: you don't fly because you'll interfere with another bird and
Speaker 1: you'll both fall, and angular alignment, meaning that you're following
Speaker 1: a neighboring bird's directional movement. Pessendorfer said, depending on how
Speaker 1: you change those three parameters, you can get everything from
Speaker 1: those barrel-looking baseballs that you get in ocean fish to
Speaker 1: loose-looking insect swarms to highly, highly organized fish swarms and murmurations.
Speaker 1: all in those three little parameters. Scientists believe these birds
Speaker 1: flock in the first place to confuse and discourage predators
Speaker 1: through their sheer numbers, with the noise such a flock
Speaker 1: makes and, of course, its motion. Some communication between birds
Speaker 1: may be happening too in murmurations, say pointing out good
Speaker 1: food sources, or the birds may simply be keeping warm.
Speaker 1: What may be most stunning to mere humans is that
Speaker 1: these birds react so quickly and do so in such synchronization,
Speaker 1: if not immediately, within a couple flaps of a bird's wings.
Speaker 1: They move almost as one in a type of lockstep or,
Speaker 1: as it were, block flap. But how? Birds can take
Speaker 1: in certain information around them and process it much more
Speaker 1: quickly than humans. They see faster than we do. They
Speaker 1: basically have a higher frame rate. Back in 1986, Craig Reynolds,
Speaker 1: an MIT-trained computer scientist, built computer models of bird flocking
Speaker 1: and fish schooling in something he called Boyds. These programs
Speaker 1: provided the basis for lifelike animation in movies, initially and
Speaker 1: notably A Swarm of Bats in the 1992 Tim Burton
Speaker 1: film Batman Returns. In applications to real life, the ability
Speaker 1: to understand the behavioral movements of large groups of starlings
Speaker 1: or bats or bees or whatever, and to program swarms
Speaker 1: of robots into making similar movements has amazing possibilities. This
Speaker 1: is called biomimicry or biomimetics. An example, Las Cumbres Observatory
Speaker 1: has 22 robotic telescopes on seven sites around the world
Speaker 1: that coordinate with each other to function as one big telescope.
Speaker 1: From the LCO website, It's called time-domain astronomy, which means
Speaker 1: that we can continually watch phenomena in space as they change.
Speaker 1: When we get to see the big picture as it unfolds,
Speaker 1: we're able to learn more, learn it faster, and dramatically
Speaker 1: increase our understanding of the forces that drive the universe.
Speaker 1: Another example, the emerging field of swarm robotics uses information
Speaker 1: gleaned from the study of starlings that could, according to
Speaker 1: the Wyss Institute at Harvard, quote, enable new approaches for
Speaker 1: search and rescue missions, construction efforts, environmental remediation, and medical applications.
Speaker 1: Swarm robotics could also have use in military applications like
Speaker 1: micro drones released from fighter aircraft. A swarm of self-driving
Speaker 1: cars working together could help reduce or eliminate traffic jams,
Speaker 1: all from watching, studying, learning, and building on the wondrous
Speaker 1: flocking of this simple bird. Piesendorfer said, As humans who
Speaker 1: have very complicated decision-making processes, we're not used to looking
Speaker 1: at simple decision-making processes that scale up to what looks
Speaker 1: like complex behavior. These models help us understand these types
Speaker 1: of patterns. Today's episode is based on the article, The
Speaker 1: Secrets and Science Behind Starling Murmurations, on HowStuffWorks.com, written by
Speaker 1: John Donovan. BrainStep is a production of iHeart Podcasts in
Speaker 1: partnership with HowStuffWorks.com and is produced by Tyler Klang. For
Speaker 1: more shows from iHeart Podcasts, visit the iHeartRadio app, Apple Podcasts,
Speaker 1: or wherever you listen to your favorite shows.