Language origines, birds, primates and humans

[trehinp]

In the discussion The hominin fossil record: taxa, grades and clades, « on: August 01, 2008, 09:42:20 AM »
(Click here for the whole discussion) the theme of early evolutionary process which could potentially have ben leading to language was mentioned. Here are the starting posts on that subject.

PAUL

The third reference [on living creature classifications] (http://tolweb.org/tree) provided the level of information I needed at this point in time. I Wanted to see how far down on the evolution tree it would be necessary to go to found a common ancestor to modern humans and modern birds...

This may sound like a strange endeavour, but here is the question I have in mind:

There are several aspects where some birds have closer resemblance to human being that do other primates.

For example, birds who learn their songs have a closer variation of the Fox-P2 gene compared to that of human beings than other primates outside human being have. In some categorisation tasks, some birds show astonishing abstraction capabilities, some birds even have a better "theory of mind" than do great apes.

Would have it been possible that in the evolution process some primate would have kept the genes variations that was present in those birds while other primates would have lost it or have had mutations that curtailed a loss of the function? Hence explaining why some primates developed language and other cognitive skills while other primates didn't develop language and similar cognitive skills as humans...

Looking at the tree in the website I saw that one has to go very far down to find a common ancestor to birds and primates...

I have no special knowledge in genetics so this is purely a wild question...

Well, it doesn't cost much asking a question, does it?

Paul

STEVE

This is an extremely difficult question to answer and to investigate (it's on-going), and it encompasses several different disciplines: linguistics, philosophy, psychology, biology, anthropology, palaeontology.

funny thing you asked because i wrote a research paper in my early graduate days on ALR - ape language research. let me go back and find it, later today, and see what i wrote on the subject. i believe, at least for non-human primates, the answer is no for language. birds are a different bag of worms; they are Class Aves (vs. Class Mammalia). compared to the first primates, we are talking about a difference in hundreds of millions of years of evolutionary history.

in the meantime, two things should be considered:

1. what is the definition of language?
2. what about convergent evolution, or the more technical jargon, homoplasy?

- Steve

A discussion, in which some elements were common to this one, started in Language recursion in Starlings  « on: April 28, 2006, 08:03:14 AM »
(Click here for more on that discussion)

I think this could be an interesting discussion to pursue…

Paul

[S. L. Wang]

Here are parts of what I found and wrote about ALR...

There are two basic criteria for language: semantics and syntax. Semantics refers to the referential signals between symbols to objects and actions; for example, “X is the sign for Y” (Seyfarth, 1986). Syntax, defined by Chomsky (1979), is a system of rules that specify the properties of expressions. In other words, syntax dictates the ordering of semantics. In our (human) language, syntax is called grammar.

Expanding beyond those two basic constituents, the definition of language becomes inconsistent. This is particularly true, as Goldin-Meadow (1993, p. 63) noted, that “language is not tied to the mouth and ear but can also be processed by the hand and eye.” Hence speech, albeit an important asset in “normal” human communication, is not what defines language. The American Sign Language (Ameslan or ASL) provides ample evidence to support this assessment. The inability to “speak,” due to anatomical differences in the vocal tract and the cortical regions (Lieberman et al., 1972; Steklis and Raleigh, 1979), then, should not automatically accord apes a non-linguistic status. To do so would imply, a priori, that the deaf do not have language either.


Several notable ALR projects in the States (and these are by no mean comprehensive):
1. Project Washoe
- researchers: the Gardners, University of Nevada
- subject: wild-born female common chimpanzee (Pan troglodytes), acquired in 1966
- protocol: American Sign Language (ASL) through molding (physically-guided imitation) and shaping (a rewarding practice based on sign approximation)
- duration: 51 months
- results: acquired 132 signs
- criticism: Washoe was merely signing regular patterns, demonstration of syntax is inconclusive

2. Project Sarah
- researcher: Premack, University of California at Santa Barbara
- subject: wild-born female common chimp, acquired in 1964, training started at age 5
- protocol: metal-backed, plastic chips of varying size, shape, color, and texture to function as words (created by Premack)
- duration: ?
- results: ?
- criticism: incentive-based problem solving skills, much like the conditioned behaviors seen in rats/pigeons; memorized the correct chip position and sequence

3. LANA (Language Analogue) Project
- researchers: Rumbaugh and colleagues, Yerkes Regional Primate Center in Atlanta, GA
- subject: female common chimp born at the Center in 1970, training started at age 28-months (in 1972)
- protocol: an array of abstract symbols, or lexigrams, set on a computer keyboard inside the subject’s cage; language was invented by the psycholinguist Ernst von Glaserfeld; researchers dubbed it Yerkish
- duration: ?
- results: ?
- criticism: keys of different semantic classes were color-coded --> likelihood of sequential color learning cannot be ignored; took 1,600 trials for her to learn how to properly use the lexigram please in her request --> conditioned, discriminative learning

4. Project Nim
- researchers: Terrance and colleagues, Columbia University
- subject: captive-born, two-weeks-old, male common chimp named Nim Chimpsky (after the eminent linguist Noam Chomsky); training began at age 9-months
- protocol: pidgin sign language, or a reduced form of true ASL
- duration: 17 months
- results: 125 signs
- criticism (from the research team): signing an utterance repeatedly until a desired action would result; imitations most likely functioned as a mean for Nim to obtain rewards from his trainers

5. Project Kanzi - still generating publication
- researchers: Savage-Rumbaugh and colleagues, Yerkes Regional Primate Research Center in Atlanta, GA
- subject: male bonobo (Pan paniscus) born at the Center in fall 1980
- protocol: acquired language skills (i.e. the understanding of the lexigram system) without explicit training; a speech synthesizer was later added to his keyboard, so each time a lexigram was pressed, the corresponding word was made audible
- duration: likely still on-going
- results: first indication of abilities occurred at 18 months; further demonstrated comprehension of spoken English; at the age 6, able to identify 150 lexigram symbols through human speech
- criticism: still centered on the issue of syntax - simple grammatical pattern was evident in his preference for the action-object order in two-word combination; however, critics say that the simplicity of two-word combination required no syntactic analysis on Kanzi’s part; he could have “formed appropriate associations between these words and their corresponding things and actions" - in other words, he was doing the “know how,” not the “know what.”


Points of Reflections:
- From a theoretical respect, no universal definition of language exists. So, it is easier to impose a stricter standard of language competence to measure apes than humans.

- From a methodological respect, there are disagreements over what is and should be considered good data. For instance, crucial behavioral data are sometimes unquantifiable because they cannot be duplicated. Without repeatability, data cannot be entered into an analysis because they cannot be justified by our current scientific standards.

- The evidence for referential abilities, or semantics, is superb and strong.

- In contrast, the evidence for syntactic abilities is either lacking or unpersuasive. This is exemplified by the recurring argument of whether or not chimpanzees understood the sign-order from a structural standpoint (particularly for a complex sign-order), versus whether or not they recognized the sign-order from habitual use and/or conditioned learning. At the present, the ALR projects have not completely succeeded in presenting a cogent case for the former claim.

- For the past decade, there has been a shift from a linear, information-processing model (emphasizing language acquisition) to a dynamic system approach (emphasizing ape cognition), so the last words on ape-language research have not yet been said...


Pardon any error that I've made while copy/paste text around.
Steve

[trehinp]

Thanks for all these references Steve.

On the definitions of languages I agree that it is a rather confusing domain. Concerning language evolution it is even more hazardous, so much that the subject was taboo for almost a century... I liked Michael Corbalis book "From Hand to Mouth, The Origins of Language", Princeton University Press, Princeton 2002 which gave a rather complete overview of the subject.

The major part of experiments with language learning ( keeping a loose definition for the moment) were made with apes and so far with rather limited success except for some transmission between Washoo and her baby to whom she taught some of the ASL she had learned. Recently interesting experiments were done with non deaf infants, teaching them ASL, they confirmed that the motor mechanisms for vocal expression came later than the comprehension of language and the desire to communicate. Those infants were able to express a lot of the basic needs using ASL, which in turn reduced rather drastically the crying and tantrums, but that's besides the point...

So indeed in the development of language by apes it is clear that their vocal system is not capable of producing speech. But even their use of ASL was rather limited and always started through human intervention.

Note that this is not the case with young deaf children. I don't remember the ref right nox but a community of deaf children somewhere in Central America was pretty much left to itself and rapidly children developed their own sign language, developing both semantic and syntax as researchers later discovered. This is quite an important remark since it shows that human brain will enable the development of a language even if not a spoken one.

To come back to the analogy with birds "languages" a few experiments have been made on their learning abilities. And yes, these too lack the scientific reproductibility. Some really sticking observations have been made on parrots who didn't only "parrot" human language but appear to understand the purpose (in part) and use some of their abilities to communicate. Again, I will have to find the references...

I've found again a 2004 paper that was mentioning the analogy of Fox-P2 gene variation in birds and humans here is the concluding remark:

"We definitely don’t think that FoxP2 is the single causal gene for vocal learning," he said. "The difference between vocal learners and nonlearners -- whether between humans and nonhuman primates; or between learning and nonlearning birds -- is most likely to arise in connections of forebrain areas to motor neurons that control the voice. It is intriguing though that an ancient gene like FoxP2 appears to have something to do with learned vocalizations both in humans and in birds.
                                                                                                                                  Dennis Meredith
Click here for more

Interestingly enough, some birds are capable of cognitive feats that are very important in language development as for example categorization (which is an element of classification), theory of mind (which enables a great economy in communication between individuals) and very astonishing behaviors such as deceit, teasing, and even art (The Bower bird capability to purposefully creating extremely aesthetic bowers, so far the only other animal beside human beings known to produce aesthetic artifacts that aren't just the result of a more efficient nest structure). But that last point is getting away from language development...

As I will find back references for bird’s cognitive abilities I will post them here... Several excellent BBC programs also attracted my attention on birds... We are far away from the usual "Bird brain"  (Cervelle d'oiseau) idea of very stupid animals...

Paul

[trehinp]

More on early language development.

Primate Vocalization, Gesture, and the Evolution of Human Language
Michael A. Arbib,
Katja Liebal, and
Simone Pika
CURRENT ANTHROPOLOGY Volume 49, Number 6, December 2008
© 2008 by The Wenner-Gren Foundation for Anthropological Research. All rights reserved.
0011-3204/2008/4906-0004$10.00
DOI: 10.1086/593015

The performance of language is multimodal, not confined to speech. Review of monkey and ape communication demonstrates greater flexibility in the use of hands and body than for vocalization. Nonetheless, the gestural repertoire of any group of nonhuman primates is small compared with the vocabulary of any human language and thus, presumably, of the transitional form called protolanguage. We argue that it was the coupling of gestural communication with enhanced capacities for imitation that made possible the emergence of protosign to provide essential scaffolding for protospeech in the evolution of protolanguage. Similarly, we argue against a direct evolutionary path from nonhuman primate vocalization to human speech. The analysis refines aspects of the mirror system hypothesis on the role of the primate brain's mirror system for manual action in evolution of the human language-ready brain.

Sound like an interesting paper. Unfortunately only accessible to subscribers or on a pay per view basis. Click here for more

Any comments on the paper for those who have access?

Paul