Category Archives: Birdsong and Language

RE: A simple explanation for the evolution of complex song syntax in Bengalese finches by Anthony Olszewski

RE: A simple explanation for the evolution of complex song syntax in Bengalese finches
by Anthony Olszewski

The comments below concern
A simple explanation for the evolution of complex song syntax in Bengalese finches
Kentaro Katahira, Kenta Suzuki, Hiroko Kagawa, Kazuo Okanoya
. . .
For the complete commentary, please see:

Sound Analysis Tools for Matlab & Bird-Puffer system

Ofer Tchernichovski
to birdsong-L

Dear friends,

We would like to share with you two methods and software tools we developed: Sound Analysis Tools for Matlab, and a system, which we call ‘Bird-puffer’, for rapid auditory discrimination training of zebra finches using social reinforcement.

Sound Analysis Tools for Matlab (SAT) is similar to Sound Analysis Pro, but is modular and easy to manipulate and combine with your own code. It should be useful even without any coding: the user interface is similar to that of SAP, and it can be used for exploring sounds, extracting features, and calculating similarity. Through Matlab, these tools are now available for both Mac and PC users.

Click here for download and more information (including user manual).      I am happy to answer questions.

Bird-puffer is a combined software/hardware solution to rapidly train zebra finches to discriminate between songs. It can be used to train naïve birds within 3 hourly sessions, while experienced birds can lean to discriminate between songs within several minutes. Zebra finches love to socialize and they never seem to get enough of it. The system includes two cages with a little window for socializing. By choosing to socialize next to the window, the bird will voluntarily risk receiving an air-puff (harmless but unpleasant), which our software associates with specific sounds. Birds quickly learn to escape the air puff by flying away after hearing those sounds. Click here for downloading the software (for Windows only) and for hardware installation instructions. Kirill Tokarev (who co-developed this system) and I will be happy to answer questions.

We hope you will find these useful,

Happy New Year!

Kirill & Ofer

The vocal repertoire of the domesticated zebra finch: a data-driven approach to decipher the information-bearing acoustic features of communication signals

Although a universal code for the acoustic features of animal vocal communication calls may not exist, the thorough analysis of the distinctive acoustical features of vocalization categories is important not only to decipher the acoustical code for a specific species but also to understand the evolution of communication signals and the mechanisms used to produce and understand them.

Here, we recorded more than 8,000 examples of almost all the vocalizations of the domesticated Zebra finch, Taeniopygia guttata: vocalizations produced to establish contact, to form and maintain pair bonds, to sound an alarm, to communicate distress or to advertise hunger or aggressive intents. We characterized each vocalization type using complete representations that avoided any a priori assumptions on the acoustic code, as well as classical bioacoustics measures that could provide more intuitive interpretations. We then used these acoustical features to rigorously determine the potential information-bearing acoustical features for each vocalization type using both a novel regularized classifier and an unsupervised clustering algorithm. Vocalization categories are discriminated by the shape of their frequency spectrum and by their pitch saliency (noisy to tonal vocalizations) but not particularly by their fundamental frequency. Notably, the spectral shape of zebra finch vocalizations contains peaks or formants that vary systematically across categories and that would be generated by active control of both the vocal organ (source) and the upper vocal tract (filter).

. . .

Click on the Link below to access the complete paper:

Universal mechanisms of sound production and control in birds and mammals

Universal mechanisms of sound production and control in birds and mammals

C.P.H Elemans, J.H. Rasmussen, C.T. Herbst, D.N. Düring, S.A. Zollinger, H. Brumm, K. Srivastava, N. Svane, M. Ding, O.N. Larsen, S.J. Sober & J.G. Švec

Nature Communications 6, Article number: 8978 doi:10.1038/ncomms9978
Received 24 March 2015 Accepted 22 October 2015 Published 27 November 2015

As animals vocalize, their vocal organ transforms motor commands into vocalizations for social communication. In birds, the physical mechanisms by which vocalizations are produced and controlled remain unresolved because of the extreme difficulty in obtaining in vivo measurements. Here, we introduce an ex vivo preparation of the avian vocal organ that allows simultaneous high-speed imaging, muscle stimulation and kinematic and acoustic analyses to reveal the mechanisms of vocal production in birds across a wide range of taxa. Remarkably, we show that all species tested employ the myoelastic-aerodynamic (MEAD) mechanism, the same mechanism used to produce human speech. Furthermore, we show substantial redundancy in the control of key vocal parameters ex vivo, suggesting that in vivo vocalizations may also not be specified by unique motor commands. We propose that such motor redundancy can aid vocal learning and is common to MEAD sound production across birds and mammals, including humans.

. . .

Access the paper here:

A bird’s eye view of human language evolution

Robert C. Berwick1,2*, Gabriël J. L. Beckers3, Kazuo Okanoya4 and Johan J. Bolhuis5
1 Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
2 Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
3 Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany
4 Department of Cognitive and Behavioral Sciences, The University of Tokyo, Tokyo, Japan
5 Behavioural Biology, Helmholtz Institute, University of Utrecht, Utrecht, The Netherlands
Comparative studies of linguistic faculties in animals pose an evolutionary paradox: language involves certain perceptual and motor abilities, but it is not clear that this serves as more than an input–output channel for the externalization of language proper. Strikingly, the capability for auditory–vocal learning is not shared with our closest relatives, the apes, but is present in such remotely related groups as songbirds and marine mammals. There is increasing evidence for behavioral, neural, and genetic similarities between speech acquisition and birdsong learning. At the same time, researchers have applied formal linguistic analysis to the vocalizations of both primates and songbirds. What have all these studies taught us about the evolution of language? Is the comparative study of an apparently species-specific trait like language feasible? We argue that comparative analysis remains an important method for the evolutionary reconstruction and causal analysis of the mechanisms underlying language. On the one hand, common descent has been important in the evolution of the brain, such that avian and mammalian brains may be largely homologous, particularly in the case of brain regions involved in auditory perception, vocalization, and auditory memory. On the other hand, there has been convergent evolution of the capacity for auditory–vocal learning, and possibly for structuring of external vocalizations, such that apes lack the abilities that are shared between songbirds and humans. However, significant limitations to this comparative analysis remain. While all birdsong may be classified in terms of a particularly simple kind of concatenation system, the regular languages, there is no compelling evidence to date that birdsong matches the characteristic syntactic complexity of human language, arising from the composition of smaller forms like words and phrases into larger ones.

Click HERE for the complete article.

MIT — Paper amplifies hypothesis that human language builds on birdsong and speech forms of other primates

New paper amplifies hypothesis on human language’s deep origins
Amplifies hypothesis that human language builds on birdsong and speech forms of other primates


On the island of Java, in Indonesia, the silvery gibbon, an endangered primate, lives in the rainforests. In a behavior that’s unusual for a primate, the silvery gibbon sings: It can vocalize long, complicated songs, using 14 different note types, that signal territory and send messages to potential mates and family.

Far from being a mere curiosity, the silvery gibbon may hold clues to the development of language in humans. In a newly published paper, two MIT professors assert that by re-examining contemporary human language, we can see indications of how human communication could have evolved from the systems underlying the older communication modes of birds and other primates.

From birds, the researchers say, we derived the melodic part of our language, and from other primates, the pragmatic, content-carrying parts of speech. Sometime within the last 100,000 years, those capacities fused into roughly the form of human language that we know today.

But how? Other animals, it appears, have finite sets of things they can express; human language is unique in allowing for an infinite set of new meanings. What allowed unbounded human language to evolve from bounded language systems?

“How did human language arise? It’s far enough in the past that we can’t just go back and figure it out directly,” says linguist Shigeru Miyagawa, the Kochi-Manjiro Professor of Japanese Language and Culture at MIT. “The best we can do is come up with a theory that is broadly compatible with what we know about human language and other similar systems in nature.”

Specifically, Miyagawa and his co-authors think that some apparently infinite qualities of modern human language, when reanalyzed, actually display the finite qualities of languages of other animals — meaning that human communication is more similar to that of other animals than we generally realized.

“Yes, human language is unique, but if you take it apart in the right way, the two parts we identify are in fact of a finite state,” Miyagawa says. “Those two components have antecedents in the animal world. According to our hypothesis, they came together uniquely in human language.”

Introducing the ‘integration hypothesis’

The current paper, “The Integration Hypothesis of Human Language Evolution and the Nature of Contemporary Languages,” is published this week in Frontiers in Psychology. The authors are Miyagawa; Robert Berwick, a professor of computational linguistics and computer science and engineering in MIT’s Laboratory for Information and Decision Systems; and Shiro Ojima and Kazuo Okanoya, scholars at the University of Tokyo.

The paper’s conclusions build on past work by Miyagawa, which holds that human language consists of two distinct layers: the expressive layer, which relates to the mutable structure of sentences, and the lexical layer, where the core content of a sentence resides. That idea, in turn, is based on previous work by linguistics scholars including Noam Chomsky, Kenneth Hale, and Samuel Jay Keyser.

The expressive layer and lexical layer have antecedents, the researchers believe, in the languages of birds and other mammals, respectively. For instance, in another paper published last year, Miyagawa, Berwick, and Okanoya presented a broader case for the connection between the expressive layer of human language and birdsong, including similarities in melody and range of beat patterns.

Birds, however, have a limited number of melodies they can sing or recombine, and nonhuman primates have a limited number of sounds they make with particular meanings. That would seem to present a challenge to the idea that human language could have derived from those modes of communication, given the seemingly infinite expression possibilities of humans.

But the researchers think certain parts of human language actually reveal finite-state operations that may be linked to our ancestral past. Consider a linguistic phenomenon known as “discontiguous word formation,” which involve sequences formed using the prefix “anti,” such as “antimissile missile,” or “anti-antimissile missile missile,” and so on. Some linguists have argued that this kind of construction reveals the infinite nature of human language, since the term “antimissile” can continually be embedded in the middle of the phrase.

However, as the researchers state in the new paper, “This is not the correct analysis.” The word “antimissile” is actually a modifier, meaning that as the phrase grows larger, “each successive expansion forms via strict adjacency.” That means the construction consists of discrete units of language. In this case and others, Miyagawa says, humans use “finite-state” components to build out their communications.

The complexity of such language formations, Berwick observes, “doesn’t occur in birdsong, and doesn’t occur anywhere else, as far as we can tell, in the rest of the animal kingdom.” Indeed, he adds, “As we find more evidence that other animals don’t seem to posses this kind of system, it bolsters our case for saying these two elements were brought together in humans.”

An inherent capacity

To be sure, the researchers acknowledge, their hypothesis is a work in progress. After all, Charles Darwin and others have explored the connection between birdsong and human language. Now, Miyagawa says, the researchers think that “the relationship is between birdsong and the expression system,” with the lexical component of language having come from primates. Indeed, as the paper notes, the most recent common ancestor between birds and humans appears to have existed about 300 million years ago, so there would almost have to be an indirect connection via older primates — even possibly the silvery gibbon.

As Berwick notes, researchers are still exploring how these two modes could have merged in humans, but the general concept of new functions developing from existing building blocks is a familiar one in evolution.

“You have these two pieces,” Berwick says. “You put them together and something novel emerges. We can’t go back with a time machine and see what happened, but we think that’s the basic story we’re seeing with language.”

Miyagawa acknowledges that research and discussion in the field will continue, but says he hopes colleagues will engage with the integration hypothesis.

“It’s worthy of being considered, and then potentially challenged,” Miyagawa says.


CIDRAP — Avian flu in South Korea, Taiwan prompts massive culling

Robert Roos | News Editor | CIDRAP News | Mar 05, 2015

South Korea and Taiwan have destroyed more than 2.7 million poultry in recent weeks and months in efforts to halt highly pathogenic avian influenza (HPAI) outbreaks of the H5N8 and H5N2 varieties, according to reports posted yesterday by the World Organization for Animal Health (OIE).

In addition, South Vietnam has reported another H5N1 avian flu outbreak, and low-pathogenicity avian flu (LPAI) H7N7 recently struck a turkey farm in Germany, according to media and OIE reports.

Click HERE for the complete article.

The Bengalese finch, domestication and the origin of Language — Comments on Okanoya’s hypothesis

In this video, Dr. Okanoya’s hypothesis is that Evolution of song complexity in finches might mirror evolution of language in humans.

The origin of the human capacity for Language is a central question and any small step towards an answer would be a towering achievement. Unfortunately, Dr. Okanoya’s work does not accomplish that. As neither a sub-species of White-rumped Munia nor a strain of Bengalese is specified, the experiment can’t be reproduced. Since the White-rumped Munia used didn’t receive appropriate care, the observations very likely only reflect that flawed husbandry. Also, there’s no recording of the White-rumped Munia song in the natural state.

There are a number of different sub-species of White-rumped Munias and a constellation of domestic varieties. In the research reviewed in the video, the wild birds are defined as from three locations in Taiwan. This was not done in previous song complexity research by Honda and Okanoya:
It’s stated that “White-backed munias were caught in the wild and imported through Hong Kong. We obtained White-backed Munias from two different pet suppliers.”
Were the White-rumped Munias shipped from Hong Kong also collected there and so a single-subspecies? Or, were the birds from a number of locations with different sub-species? Since the White-rumped Munia is a major species in the Chinese Prayer Bird Trade,
it’s quite possible that the birds belonged to a number of different Lonchura striata sub-species from outside Hong Kong.

That there are various Bengalese stocks that trace back to different Lonchura striata populations, Taka-Tsukasa notes here:
The Bengalee can be easily crossed with any of the other varieties
of its kind, or such Mannikins as the Sharp-tail Finch and ‘Spice
# # #

More recently, European bird breeders produced a hybrid strain of Bengalese finches. The details of this program are not known.

Robin Restall in
Munias and Mannikins
writes of eight sub-species of Lonchura striata.

Okanoya has shown that there are genetically distinct types of the domestic Bengalese:
Were all the different domestic varieties tested for song complexity? Were they found to be identical?

White-rumped Munia and Bengalese Finches
The speculation that birdsong is somehow similar to human language is intertwined with the surmise that self-domestication was a feature of human evolution. Is one hypothesis being used to prove another?

We are shown a picture of a Bengalese and are told that “It looks like very white and very domesticated.” How exactly do the Bengalese look domesticated? Yes, white mice are domesticated, but there are many other colors of domestic mice. The bird shown is a heavy pied and indeed there are all-white Bengalese, but these are not the most common. Many Bengalese are lightly pied (mostly dark) or even completely dark. An attempt is being made to fit the Bengalese into the Domestication Syndrome chart. The pied color variety is a match, and probably increased reproductive capacity, too. Most of the other features listed either are not applicable (“floppy ears”) or are not found in the Bengalese. The discussions of domestic animals in the CARTA talks are about retained infantile traits in comparison with human evolution. White plumage is not an infantile trait in White-rumped Munias.

Of course the little White-rumped Munia displays no inter- or intra-specific aggression anything at all like wolves or great apes. A strange experiment is performed where the wild bird variety and the Bengalese are subjected to electric shocks. That the White-rumped Munia is measured as biting harder is given as evidence of increased aggression. All that’s actually shown is that the White-rumped Munia has stronger beak muscles than the Bengalese. The one with the higher level of aggression is the person tormenting the poor birds.

The research in the video appears to be reflected here:

The wild-caught birds are not properly maintained. Here:
Ecological correlates of song complexity in White-rumped Munias
the initial handling of the wild-caught birds is described:
To record songs of White-rumped Munias, we set mist nets and captured males . . . Birds were marked with colored leg rings. Because the birds were stressed when they were captured,they did not sing right away; therefore, we kept them for a few weeks to months to ensure they were habituated to the captive condition.
. . . The birds captured in 2007 and 2008 were kept in an indoor space in each capture site for about a week before recording. The situation of the captive environment was the same as the outdoor climate and daytime. All birds that were captured from the same area in the same year were kept together in large metal cages. In the captive condition, they were provided with finch seed mixture and
water ad libitum.

# # #

Exact coordinates are given for the collection sites, so it might be possible to verify the subspecies / race used. Prayer Bird release is also practiced in Taiwan. As these might be other subspecies of Lonchura striata, just knowing the location may not be enough for identification. Each bird should have been banded with a coded / numbered band. That way, there would be no questions about the identity of any particular bird or its original location. It also would have been good if photos were taken of each bird, both the wild Lonchura striata and the domesticated Bengalese used in the study.

Was any attempt made to observe the Lonchura striata in nature to determine the song complexity there? If yes, were recordings made? Did the song of these birds in nature show the same lower level of complexity as heard in the laboratory?

It’s not reasonable to expect wild-caught birds ever really to habituate to a cage or even a small flight. Every living thing tries to remain so and then to reproduce. That captive animals don’t die and manage to produce offspring demonstrates only that husbandry is at least minimal, not optimal. There’s no reason to expect the behavior of wild animals in captivity to be the same as in the natural state.

Unfortunately, as dimensions are not given, it’s impossible to know what’s meant by a “large” metal cage. The large flight cage shown here
is very roomy for a small group of the domesticated Bengalese, but is inadequate for wild-caught White-rumped Munias. To expect to observe behavior that’s a fair approximation of what one might see in nature, each pair of wild-caught White-rumped Munias should be kept in a planted flight of perhaps 1.25m X 2.25m X 2.25m. It also would be good to find out how far these birds nest from each other in the natural state. If they don’t nest within sight of each other, then flights, at the very least, can’t be adjoining.

Unless an attempt is made to provide something like an environment suitable for non-domesticated birds, what’s very likely to happen is that a corrupted (neurotic?) variant of behavior will be delivered.

Another factor is the constant stress that a strange and unnatural environment engenders.
These responses, although temporary defense mechanisms against specific stimuli, place a bird in a state of general nonspecific stress, in which growth rates and resistance to many diseases are diminished.
Physiological Stress in Birds, H. S. Siegel
There’s no reason to expect “that domesticated songbirds have reduced CORT levels because of reduced levels of environmental stresses (compared to wild conditions).”
What’s very likely is instead for the wild-caught White-rumped Munias to have increased CORT levels because of the stress of a strange environment — captivity. This won’t change after a few generations of nests in a cage. The White-rumped Munias will continue to find life behind bars stressful for generations, indeed until a domesticated strain is developed. Another source of stress is if the wild-caught White-rumped Munias either are afflicted by disease / infested with parasites when collected or if the birds become infected from the Bengalese.

Was any attempt made to document the health of the White-rumped Munias at the time of capture? This should include inspection for external parasites (mites and lice), internal parasites (worms) and the full range of microbial pathogens? And what about the Bengalese? There’s every reason to expect any and all persistent infections of the Bengalese immediately to afflict and adversely affect the stressed White-rumped Munias. The best course would be to maintain the White-rumped Munias separated from any domestic birds.

Avian malaria has been shown to be detrimental to canary song.
Other diseases might have the same effect.

Okanoya states that
Singing is costly in two terms: the cost of being preyed upon while singing, and the cost of singing itself. Male birds are at a risk of predation when engaging in singing (Ryan et al., 1982; Yasukawa, 1989)

Concerning increased risk of predation, the first reference
Bat Predation and Sexual Advertisement in a Neotropical Anuran
Michael J. Ryan, Merlin D. Tuttle, A. Stanley Rand

discusses bats tracking frogs at night. This has no relevance to the behavior of any bird during the day.
The second reference
The cost and benefits of a vocal signal: the nest associated ‘Chit’ of the female red-winged blackbird
Ken Yasukawa

is concerned with the raiding of nests at a location that’s revealed by the hen’s call. This paper has no relevance to the singing of a courting male White-rumped munia.

I don’t know of any significant predators of song birds that hunt by
sound. My understanding is that hawks use sight. I’ve never seen
cats stalking a singing bird. Cats when hunting birds seem only
to use sight (unlike when seeking rodents where sound and air currents come into play) and target those feeding on the ground. Snakes generally focus on odor to detect prey.

Song birds can perform hidden in foliage. And for those that do their singing on a highly visible stage, it will be high up and far away from cats and with an eye towards the sky for hawks. Birds preyed on by hawks (and falcons) are very aware of the presence of danger. Just walking down my block in Jersey City, from time to time I’ll notice the absence of pigeons, starlings or sparrows — all generally common. Almost always then if I look up, I’ll see a bird of prey — perhaps just as a very small figure way up overhead.

Okanoya states that
Singing long, complex songs also have physiological cost.
but in the paragraphs that follow, there are a number of additional speculations, not proofs.

In the video above, Dr. Okanoya states:
When a female is paired with a guy with nice song, that female decides to allocate more reproductive resource to that mating.
which appears to reflect this research:
It would be interesting for another lab to perform the experiment again and have the hormone levels checked by an avian veterinarian. Bengalese finches normally are focused on reproduction, with nothing besides basic care needed to stimulate that:
Society finches possess an exceedingly strong breeding desire.

Even though Bengalese are fine models for learned vocalization, this species poses complications for comparing a domestic species to a wild ancestor. The connection between the various sub-species of the White-rumped Munia and any particular strain of Bengalese might very well elude definition and require interpretation instead. To allow for the results of an experiment investigating a difference between wild Lonchura striata and the domestic Bengalese to be repeated, the population of the White-rumped Munia and the strain of Bengalese must be specified. Better species to use might be the Australian Zebra Finch (Taeniopygia guttata), hybrids of which are not common and generally are easily recognized, and the Budgerigar (Melopsittacus undulatus), with hybrids either unknown or exceedingly rare. Both of these species are very common in the wild and definitely are the source of the domestic birds. One drawback is that Australia does not allow exports, so research on the wild populations would need to be done there.