Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The birds and the b’s: Challenging Chomsky, starlings learn ’human-only’ syntax patterns

27.04.2006
The European starling – long known as a virtuoso songbird and as an expert mimic too – may also soon gain a reputation as something of a "grammar-marm." This three-ounce bird, new research shows, can learn syntactic patterns formerly thought to be the exclusive province of humans.

Led by Timothy Q. Gentner, assistant professor of psychology at the University of California, San Diego, a study published in the April 27 issue of Nature demonstrates that starlings have the capacity to classify acoustic sequences defined by recursive, center-embedded grammars.

Recursive center-embedding refers to the common characteristic of human grammars that allows for the creation of new (and grammatically correct) utterances by inserting words and clauses within sentences – theoretically, without limit. So, for example, "Oedipus ruled Thebes" can become "Oedipus, who killed his father, ruled Thebes" or "Oedipus, who killed his father, whom he met on the road from Delphi, ruled Thebes," and so on.

Chomskian linguists have held that this recursive center-embedding is a universal feature of human language and, moreover, that the ability to process it forms the computational core of a uniquely human language facility.

"Our research is a refutation of the canonical position that what makes human language unique is a singular ability to comprehend these kinds of patterns," Gentner said. "If birds can learn these patterning rules, then their use does not explain the uniqueness of human language."

The research also contradicts the 2004 conclusions of W. Tecumseh Fitch and Marc D. Hauser based on the failure of cotton-top tamarin monkeys to learn similar grammar patterns after being exposed to strings of human speech.

"This result reinvigorates the search for the evolutionary substrates for language processing among the primates, and most excitingly gives us an animal model to probe deeper into these aspects of language," said Daniel Margoliash, who is a coauthor along with Kimberly M. Fenn and Howard C. Nusbaum at the University of Chicago.

Gentner and his coauthors created artificial starling songs that followed two different patterning rules: a "context-free" rule, which allows for a sound to be inserted in the middle of an acoustic string and is the simplest form of recursive center-embedding; and a "finite-state" rule, of the sort thought to account for all non-human communication, that allows for sounds to be appended only at the beginning or end of a string.

Capitalizing on the diverse range of sounds in starling songs, the researchers used recordings of eight different "warbles" and eight different "rattles" from a single male starling to construct a total of 16 artificial songs. Eight of these songs followed the context-free sequence AnBn (i.e. AABB or rattle-rattle-warble-warble) and eight followed the finite-state (AB)n (i.e. ABAB or rattle-warble-rattle-warble).

Eleven adult birds were then taught to distinguish these two sets of songs using classic reinforcement techniques. The birds were rewarded with food for pecking at a button when they heard a song from the context-free set and for refraining when they heard one from the finite-state set.

Nine of the starlings – after 10,000 to 50,000 trials over several months – eventually learned to distinguish the patterns.

When tested with different combinations of rattles and warbles that followed the same rules, the starlings performed well above chance, suggesting they had learned the abstract patterns and not just memorized the specific songs.

The researchers also checked to see how the birds responded to "ungrammatical" strings, ones that violated the established rules. The starlings treated these differently, as expected if they had learned the patterns.

The experimenters then asked if the birds were capable of a key feature of human grammars: Could the starlings extrapolate these patterning rules to distinguish among longer strings? Remarkably, Gentner said, after learning the patterns with songs made up of pairs of rattles and warbles, the birds were able to successfully recognize grammatical strings of three rattles-three warbles and four rattles-four warbles.

The finding that starlings can grasp even these simple grammatical rules, Gentner said, suggests that humans and other animals share basic levels of pattern recognition and also hints at the likelihood of other cognitive abilities we have in common.

"There might be no single property or processing capacity," Gentner and coauthors write, "that marks the many ways in which the complexity and detail of human language differs from non-human communication systems."

More generally, Gentner says, "The more closely we understand what nonhuman animals are capable of, the richer our world becomes. Fifty years ago, it was taboo to even talk about animal cognition. Now, there are Nova specials on the subject and no one doubts that animals have complex and vibrant mental lives. This study is a powerful statement about what even birds can do: Look at what they’re learning."

The experiments were performed at the University of Chicago when Gentner was a postdoctoral researcher there. The study is supported in part by a National Institutes of Health grant to Margoliash.

Gentner is now exploring the possibility of working with juvenile starlings, who (like human children) may be more adept than their full-grown counterparts at learning syntactical patterns.

A current study is also underway to see if starlings can apply the rules they’ve learned to novel stimuli – something humans are masters at doing. Early results suggest they don’t, leaving humans the reigning champs of generalizing from patterns.

Inga Kiderra | EurekAlert!
Further information:
http://www.ucsd.edu

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>