Seeker Archives

Great Tits Use Syntax to Chirp Complex Messages

The birds use complex syntax in their calls to convey two meanings at once.

Songbirds known as Japanese great tits have figured out how to combine tweets with distinct meanings into more complex sentences, new research finds.

The discovery is a breakthrough in understanding animal vocalizations. Before, it was difficult to prove that any animal created its own complex, structured language, but Japanese great tits appear to have done just that.

"We now have good evidence that animal communication systems share many of the basic properties of human language," said Toshitaka Suzuki, lead author of the study appearing in Nature. "For example, mammals and birds can use specific call types to denote specific objects, and Japanese great tits can combine different ‘words' to send a compound message."

10 Surprising Facts About Animal Intelligence

Suzuki is a postdoctoral fellow in the Department of Evolutionary Studies at Japan's Graduate University for Advanced Studies. Previously, he determined that Japanese great tits created distinct alarm calls to refer to two of their main nest predators: jungle crows and Japanese rat snakes.

For the new study, he and colleagues David Wheatcroft and Michael Griesser focused on a few of the Japanese great tit's different note types, which are named A, B, C and D. Prior research found that when A,B, and C are produced together in that order, the call instructs listeners to "scan for danger." The "D" note instructs listeners to "approach the caller."

When the birds tweet ABC-D together and in that order, there is a compound meaning that essentially translates to: scan for danger and come here. Suzuki and his team played the recorded calls to 21 adult Japanese great tits in the wild and the listening birds did exactly as the calls commanded, with the birds scanning the horizon and approaching the loudspeaker. When the researchers reversed the order of the notes to D-ABC, the listeners did not respond.

Bird Brothers, Coached by Dad, Form Singing Duo

The study reveals that the birds are capable of a skill known as compositional syntax - meaning they combine distinct elements of their vocalizations and extract a compound meaning from them. Before, only humans were thought to have this ability.

The talent could be common among many different songbird species.

"There is no evidence showing that non-human primates, even chimpanzees, use compositional syntax," Suzuki said, adding that "combinations of sounds are very common in tits and chickadees, and are also found in other species of passerines (perching birds)."

The birds seem to learn their various calls over time, with nestlings only emitting a limited number of call types associated with begging and distress. As they grow up, they copy their fathers' mating songs and may learn their vocalizations in other ways, too.

Songbirds Speed Tap Dance

Save for a handful of talented "polyphonic overtone" singers who can sing two notes at the same time, people are usually limited to producing one sound at a time with their vocal cords. Birds, on the other hand, "can control the two sides of their syrinx independently, allowing them to produce two different sounds simultaneously," Suzuki said.

It is known that Japanese great tits have AC, BC, AC-D and BC-D calls, as well as probably many others, all of which are not yet understood by researchers.

Robert Magrath, a professor of behavioral ecology at the Australian National University, says the research "is interesting in showing that the specific order of notes in a call can change its meaning for listeners."

Impressive Bird Flying Formations: Photos

Magrath added, "This enlarges the opportunities of complex communication from a limited repertoire of call types, and illustrates one way in which there is a similarity between human communication and that of other species."

In the future, Suzuki and his colleagues hope to learn how Japanese great tits and related species evolved such a sophisticated communication system. They also hope to better determine what is unique about human verbal skills.

It could be that we are the only species that can communicate about the future and the past - this is something that has never been detected in animal communications.

The Japanese great tit, a songbird with a diverse vocal repertoire, combines different calls using a syntactic rule to send a compound message to receivers.

Birds in flight often arrange themselves in aerodynamically optimum positions, according to a new paper in the

journal Nature

that helps to explain how birds fly in such impressive formations. Lead researcher Steven Portugal and his colleagues focused their study on northern bald ibises, but many bird species also exhibit the amazing flight behavior. Portugal, a University of London Royal Veterinary College researcher, told Discovery News that birds could be using three things to achieve their flying precision: "(1) vision – watching the bird in flight to get all the information they need, (2) feathers – sensing the changes in pressure, wind etc. through their flight feathers, and (3) positive feedback – i.e. they just fly around and when it feels easier/better they stay in that position."

The researchers determined that birds try to find "good air," meaning airflows (not just wind, but even the air created by other flapping wings) that minimize their energy expenditure and help them to get where they plan to go. Conversely, birds avoid regions of "bad air" that could work against them.

Many birds fly in distinctive V-formations. Portugal said, "The intricate mechanisms involved in V formation flight indicate remarkable awareness and ability of birds to respond to the wing path of nearby flock-mates. Birds in V formation seem to have developed complex phasing strategies to cope with the dynamic wakes (turbulent air) produced by flapping wings."

Military planes sometimes fly in what is known as an "echelon formation," which mirrors nearly the exact same flight formation of many birds. This particular bird version is a variation of the "V," only with a rounded edge.

The U.S. Navy's famous flight demonstration squadron The Blue Angels often flies in a trademark "diamond formation" once popularized by fighter-bomber pilots. In it, the pilots maintain an 18-inch wing tip to canopy separation. Birds can fly even more tightly together.

The term "murmuration" refers to a flock of starlings. These birds can create dramatic patterns in the sky, such as this one over marshlands near Tønder, Denmark. Other small birds, such as sandpipers, may also create what look to be dazzling aerial ballets in the sky as they fly en masse.

Even birds flying very close to land can do so in remarkable unison. Here, a formation was photographed as the birds flew over the beach at Camperduin in the Netherlands.

The classic "V" formation has all sorts of variations. In this case, three separate -- yet united -- groups create an arrow-like effect in the sky.

Alfred Hitchcock's classic horror film "The Birds" included many scenes where numerous birds blanketed the sky. Up close, these starlings look small and harmless but, as a huge murmuration, their power becomes evident.

From the earliest planes to those in design today, aircraft have been modeled after birds. It's no wonder. Every inch of this sleek northern bald ibis, snapped while flying over Tuscany, adds to the bird's flying prowess. Its 53-inch wingspan and powerful, synchronized wing beats must have captivated people in the ancient world too, since ancient Egyptians and other early cultures featured the birds prominently in their artwork and legends.