Humans, animals, and language: What they have in common and what they don’t Joel C. Wallenberg SEL1007 Nature of Language
November 17, 2015
How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Animals Communicate with Each Other
Some have fairly intricate systems of communication. How different are those from human language? Is it a matter of degree (we have more signs than them, and more complex messages)? Or are there qualitative differences? Are there similarities?
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How are humans and animals different?
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Bird Song
Humpback Whale Song
References
Outline
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How are humans and animals different?
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Similarities?
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Bird Song
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Humpback Whale Song
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Animals’ Capacity for Language
Can any animals be taught human language? If they can, then we are not so special. An hypothesis: Some other animal(s) have the capacity to learn a human language, but even though they do not make use of that capacity under natural conditions. (likely false) There was a famous attempt to teach a chimpanzee a type of signed language to test this idea.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Nim Chimpsky
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How are humans and animals different?
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Bird Song
Humpback Whale Song
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Project Nim
In 1973, Prof. Herbert Terrace created a lab/classroom for Nim Chimpsky, an infant chimpanzee. Nim was trained in a form of American Sign Language for 44 months, with the entire process recorded on video. Otherwise, Nim lived with humans at home (with Prof. Terrace and his student, among others...see the film Project Nim for gory and scandalous details). Ultimately, Nim learned 125 signs and could put some of them in combination with each other. (go to pdf)
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Some Rules of Nim’s Grammar
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more X much more common than X more.
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Verb X clearly more common than X Verb.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Utterances from Cecile, human, 20 months 1. Eva stamp balloon. (= Eva stamped on a balloon) 2. Eva balloon bang. 3. Eva stamp balloon bang. 4. Lady kind. Help us. 5. Ants bite you. (Here, she’s copying adults saying “Ants might bite you.”) 6. Something bite you. 7. Nick tickle you. (= Nick tickled me.) 8. Nina bounce trampoline. (= Nina bounced on the trampoline) 9. Cecile shopping Gran. (= I’m [playing at] going shopping with Gran)
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Cecile’s more-than-3-word utterances
1. Mummy going see with jamas on. (= Mummy’s going to see me when I’ve got my pyjamas on.) 2. Take that off go play in lounge. (= I want to take off my bib and go and play in the lounge.)
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Conclusion from Nim Nim was able to learn 125 words (signs) of human language. He was not able to learn the syntax of human language (apart from some very elementary word order rules). He made mistakes that are not characteristic of human language learners. This is true even though he is genetically similar to a human, and raised in a human environment. Years later, after reviewing the videotapes, Terrace (1983) concluded that most of Nim’s language use was very adept imitation of his human carers, which he used to get rewards (food, a cat, etc.). (See also interview clips in Project Nim.)
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Good try, but no cigar.
Chimps, which are very similar to humans genetically (about 98%) and in terms of intelligence, cannot learn human language like human children. No animals clearly show recursion in their communication systems, or are able to learn recursive structures. (1) [IP John said [CP that [IP Stanford beat Cal in the Big Game ]] (2) [IP John said [CP that [IP [IP Stanford beat Cal in the Big Game ] and [IP Joel liked it ] ] ]
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
What else could we look for?
Human language produces a set of sounds (or gestures) that is highly structured, i.e. it has a syntax. Human language has to be learned, in the sense that children need to match an abstract model pattern (a grammar) that they hear (or see). They have to do more than just memorising strings. The structure seems to be related to the ability to do this type of learning (grammar induction, as opposed to trial-and-error learning). Maybe grammar-learning can evolve independently of high intelligence, or other characteristics of primates.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Language Transmission / Acquisition
Adults’ I-Language
−→
Adults’ E-Language
Children’s I-Language
−→
Children’s E-Language
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Bird Song
For songbirds, such as Zebra Finches and Song Sparrows, the song is structured, with individual parts to it (song syllables). The syllables are arranged in a certain order (song syntax). Bird song has to be learned, in the sense that baby birds need to match a model pattern that they hear from adults. Like human language, the ability to learn song is innate for these species, though the specific song must be learned.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Zebra Finches
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How are humans and animals different?
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Bird Song
Humpback Whale Song
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Zebra Finch Song Syllables Tchernichovski et al. (2004)
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How are humans and animals different?
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Bird Song
Humpback Whale Song
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Zebra Finch Song Syntax
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Why are we interested? Since vocal learning did not evolve in other primates, but did evolve in a species less similar to us, maybe we have a better chance of finding the genetic basis for vocal learning. Since bird and human brains are quite different, we can ask: in what particular way are they similar enough to have vocal learning in common? If there are animals with something like human language, we have a possible animal model for studying human language. In neuroscience generally, it is difficult to study human behaviours directly in humans. Humans are very complicated. Aside from certain medical research, you cannot manipulate human brains or genetics experimentally. 18 / 41
How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Zebra Finches Male songbirds learn their song from their fathers, in general. (Slater, 2011) After hearing the song, the birds produce an imperfect copy, called subsong. The young bird continues to practice, getting closer and closer to the adult song, until it arrives at a near-perfect copy of the father’s song. Zebra Finches begin to learn song at 25 days after hatching, and can produce their first subsong at 30 days. About two weeks later, they produce identifiable song syllables. By day 90, the finch has learned the order of the syllables, and their song does not change much after that time. 19 / 41
How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Development of a Syllable
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How are humans and animals different?
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Bird Song
Humpback Whale Song
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Zebra Finch Song Learning
Zebra Finches show a critical period for song learning, from day 25-90. Similar to the critical period for human language learning (roughly in utero – pre-puberty, around age 9 according to Newport 2002).
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Innate Ability to Learn Song
If a bird is raised in isolation, it still produces a song, but one without a full song syntax (Slater, 2011). Similar to children who are deprived of language exposure during the critical period.
If a group of birds are raised in isolation, the first generation produces a simplified song, but following generations learn a full adult song using the simple song as the model (Ofer Tchernichovsky, p.c.). Similar to the emergence of sign languages, or to language varieties arising out of language contact situations.
The last two facts imply that the ability to learn song is innate.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Zebra Finch Song Development, over time (Tchernichovski et al., 2004)
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How are humans and animals different?
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Bird Song
Humpback Whale Song
References
Zebra Finch Song Development
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
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Critical Period for Song Learning
The song learning period, like the human language critical period, has been hypothesized to depend on (among other things) hormonal development and the amount of exposure to the input. Studies have shown that castration can delay the closer of the finch critical period, supporting the hormone hypothesis. Withholding an adult model song can also delay the closer of the finch critical period, showing that experience can also affect the critical period. (Derégnaucourt et al., 2004)
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Zebra Finches and Genetics A certain type of aphasia (i.e. severe language disorder) in humans has been linked to mutations in a gene called FOXP2 (Bolhuis et al., 2010, among others). Studies with Zebra Finches have shown that knocking out FOXP2 makes it impossible for finches to learn song properly. In fact, because of these studies, we know that FOXP2 allows finches to learn the adult song syntax properly; it is not the sounds that the finches get wrong, but the sequence of sounds. Similarly, humans with FOXP2 problems show similar errors. Because the finch brain and genome is so well understood, we can do controlled experiments with finches and learn something about what must be going on in the human brain. 26 / 41
How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Song Sparrows
Another aspect of human language is sociolinguistic variation. As language changes, variation arises in the population. The different variants can sometimes take on social meanings. Does any animal communication do this? In Zebra Finches we saw learning, which is necessary for change to occur. Song Sparrows take this one step further, and assign social meaning to the changes in the song.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Song Sparrow
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Song Sparrows
Male song sparrows learn their father’s song, much like Zebra Finches. But then they go out, claim some area, and learn some of the songs of their male neighbors (at least during their first Spring season (Liu’ and Kroodsma, 2006)).
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Song Sparrows
They can choose which of the songs in their repertoire to sing in response to their neighbors songs, and these have different meanings. (Beecher and Campbell, 2005) 1
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If a bird sings a song, and its neighbor sings the same song back, that is very aggressive (territorial challenge). If a bird sings a song, and its neighbor sings a different song back, but one that they share in their repertoires, that is less aggressive. If a bird sings a song, and its neighbor sings a different song back that they don’t share, that is the least aggressive.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Graveyard Study (Liu’ and Kroodsma, 2006)
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How are humans and animals different?
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Bird Song
Humpback Whale Song
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Repertoires of Two Sparrows – 3 shared songs out of 9 (Beecher and Campbell, 2005)
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How are humans and animals different?
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Bird Song
Humpback Whale Song
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Brain Area Comparison (Jarvis, 2004)
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How are humans and animals different?
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Bird Song
Humpback Whale Song
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Humpack Whale Song
Males sing a song, with different parts to it. We do not know why. All the males in a pod sing the same song, but the song changes a little bit over the singing season and they transmit changes in the song to each other. Since they are capable of spreading changes, they are capable of vocal learning. (Janik, 2011) A song can change completely over a period of 12 years (faster than human language, if whales live around 50 years or more).
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Humpback Whale
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How are humans and animals different?
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Bird Song
Humpback Whale Song
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Humpack Whale Social Situation As with human language contact, the social situation matters with whale song. (We don’t know why, but the song seems to have social meaning.) This makes sense, since humpback whales are social animals, like humans (much more so than songbirds). The humpback population off the east coast of Australia was invaded by males from the west coast. The song of the east coast whales changed completely to the west coast song in 2 years (not the usual 12 for complete song change). Like humans, song contact can create more radical changes in the song of a population than internal change.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Conclusions
No animals have been discovered to have communication systems like human language, in terms of its complexity of structure (especially recursion). Vocal learning and transmission evolved in humans, but not in any other primates. It is not a feature of the primate family. You can’t teach a chimp human language. It is not a feature of primate intelligence.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
Conclusions However, vocal learning (of a grammar) has evolved independently in other species (some cetacean species and some bird species). Note that vocal learning is not dependent on intelligence. Since these species are very different from humans, it is a golden opportunity to identify the ways that humans, whales, and songbirds are similar. Studies with other species can tell us a lot about how human brains might learn language, and how language evolved genetically (e.g. FOXP2). For more on Zebra Finches, watch the videos here! http://ofer.sci.ccny.cuny.edu/
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
References I Beecher, M.D., and S.E. Campbell. 2005. The role of unshared songs in singing interactions between neighbouring song sparrows. Animal behaviour 70:1297–1304. Bolhuis, J.J., K. Okanoya, and C. Scharff. 2010. Twitter evolution: converging mechanisms in birdsong and human speech. Nature Reviews Neuroscience 11:747–759. Derégnaucourt, S., P.P. Mitra, O. Fehér, K.K. Maul, T.J. Lints, and O. Tchernichovski. 2004. Song development: In search of the error-signal. Annals of the New York Academy of Sciences 1016:364–376. Janik, Vincent M. 2011. Vocal communication in cetaceans. In The Oxford handbook of language evolution, ed. Maggie Tallerman and Kathleen R. Gibson. Oxford: Oxford University Press. 39 / 41
How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
References II Jarvis, Erich D. 2004. Learned birdsong and the neurobiology of human language. Annals of the New York Academy of Sciences 1016:749–777. Liu’, Wan-Chun, and Donald E. Kroodsma. 2006. Song learning by chipping sparrows: when, where, and from whom. The Condor 108:509–517. Newport, Elissa L. 2002. Critical periods in language development. In Encyclopedia of cognitive science, ed. Lynn Nadel, 737–740. London: Macmillan. Slater, Peter. 2011. Bird song and language. In The Oxford handbook of language evolution, ed. Maggie Tallerman and Kathleen R. Gibson. Oxford: Oxford University Press.
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How are humans and animals different?
Similarities?
Bird Song
Humpback Whale Song
References
References III
Tchernichovski, O., TJ Lints, S. Deregnaucourt, A. Cimenser, and PP Mitra. 2004. Studying the song development process: rationale and methods. Annals of the New York Academy of Sciences 1016:348–363. Terrace, Herbert S. 1983. Apes who talk: language or projection of language by their teachers? In Language in primates, 19–42. Springer.
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