Monday, November 5, 2007

Baboon Metaphysics I

In their new Book, „Baboon Metaphysics“, Dorothy Cheney and Robert Seyfarth have some interesting things to say about language evolution. The book's title refers to a statement Charles Darwin scribbled in one of his notebooks:
"Origin of man now proved. – Metaphysics must flourish. – He who understands baboon would do more towards metaphysics than Locke.”
As Dan Dennett (1995) puts it, the idea of evolution is universal acid, transforming every world-view, yielding new perspectives on every aspect of life, impacting on our view of what it is to be human, and what makes us human.
Through their research on baboons in the Okavango Delta in Botswana, Cheney and Seyfarth have gained new insights into how
"evolution acts on the communication and cognition of animals that live in large social groups.” (p. 251)
Baboons show remarkable skills in keeping track not only of the relationships between themselves and other group members, but also in recognizing the “close bonds that exist among other members of their groups.” To test this, Cheney, Seyfarth and their team did some ingenious experiments by playing simulated vocal communications of existing group members that violated the linear transitive dominance hierarchy of the group, for example, fear barks of higher female which were directed at a female of a lower rank. The baboons looked towards the speaker for a longer period of time if the recording violated the actual hierarchy, suggesting that baboons have a mental representation and therefore expectations of the interactions and hierarchy systems within their group. Other experiments also showed that baboons are indeed quite sophisticated when it comes to understanding the complexities of their social group.
Two implications for language evolution, are I think, especially interesting. First, one crucial component of our ability to use language is having a Theory of Mind, that is the ability to attribute mental states to others. And
“although baboons and other monkeys probably do not recognize when someone is attempting to manipulate their beliefs, they may recognize when someone is attempting to manipulate their intent. They integrate social cues, gaze direction, and call type when making these assessments and when announcing their intentions to others. A rudimentary understanding of intentions and motives represents a crucial first step toward a communication system like language, in which speakers and listeners routinely assess each other’s motives, beliefs, and knowledge.” (p. 183)
Baboons certainly do not have a full-fledged Theory of Mind like humans, and in some aspects fail rather poorly at recognizing other’s mental states, for example the anxiety and fear their children endure during water-crossing, where they seem to assume that, when they can make the water crossing, everyone can, or when trying to hide from an aggressive male. But they hint at how a social mind evolves, and what the cognitive precursors for our own ToMs probably looked like.
The other implication regards the baboons' ability to form mental representations, concepts of the outside world. This suggests an evolutionary scenario in which thought came first, then language. as Cheney and Seyfarth put it: “3. In primate groups, natural selection has favored individuals who can form mental representations of other individuals, their relationships, and their motives” (p. 251). But they even go further:
“4. This social knowledge constitutes a discrete, combinatorial system of representations - a language of thought – that shares several features with human language. 5. The language of thought that has evolved in baboons and other primates is a general primate characteristic whose appearance predates the evolution of spoken language in our hominid ancestors. 6. The prior evolution of social cognition created individuals who were preadapted to develop language. 7. Several features thought to be unique to language – for example, discrete combinatorics and the encoding of propositional information – were not introduced by language. They arose, instead, because understanding social life and predicting others’ behavior requires a particular style of thinking.” (p. 251f.)
The last part is especially interesting. The idea of the ‘language-ready brain’ is of course not new, and is embraced by many scholars interested in the evolution of language, but the claim that a “social syntax” with a recursive structure is the evolutionary foundation of modern language, is, I think, quite compelling, although it contradicts Derek Bickerton’s (1990) notion of a “protolanguage” without syntax. This, too, refutes Alison Wray’s (2002) hypothesis that technology and culture stagnated between 1,4 and 0,5 million years because there were no names for actions or things, since primates clearly can conceptualize actions, and therefore a proto-language should be able to express them.
(A better explanation for this stagnation is given by Ray Kurzweil in his TED-Talk, namely the inherent exponential nature of technological progress, which allows for ever faster periods of rapid acceleration.)
It is however, in accordance with the claim made by Hauser, Chomsky and Fitch in 2002 that recursion and its mappings to the interfaces as they form the uniquely human part of the human language faculty “may have evolved for reasons other than language” (Hauser/Chomsky/Fitch 2002: 1571) and that recursion could be an exaptation that originally “evolved to solve other computational problems such as navigation, number quantification, or social relationships” (Hauser/Chomsky/Fitch 2002: 1578), although Hauser, Chomsky, Fitch insisted that recursion in general was uniquely human.
In my next post, I will come back to what it means for our conceptual system to be build upon evolutionary older foundations.

Bickerton, Derek. 1990. Language and Species. University of Chicago Press, Chicago.

Dennet, Daniel C. 1995. Darwin’s Dangerous Idea: Evolution and the Meanings of Life. New York: Simon & Schuster.

Cheney, Dorothy L. and Robert M. Seyfarth. 2007. Baboon Metaphysics: The Evolution of a Social Mind. University of Chicago Press, Chicago.

Hauser, Marc D., Noam Chomsky and W. Tecumseh Fitch 2002. “The Faculty of Language: What Is It, Who Has It, and How Did It Evolve?” In: Science 298, 1569-1579.

Wray, Alison.“Dual Processing in Protolanguage: Performance without Competence.” In: Wray, Alison. (Ed.) The Transition to Language. Studies on the Evolution of Langauge 2. Oxford, OUP.

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