Language Evolution and Computation Bibliography

Human beings are talkative. What advantage did their ancestors find in communicating so much? Numerous authors consider this advantage to be “obvious” and “enormous”. If so, the problem of the evolutionary emergence of language amounts to explaining why none of the other primate species evolved anything even remotely similar to language. What I propose here is to reverse the picture. On closer examination, language resembles a losing strategy. Competing for providing other individuals with information, sometimes striving to be heard, makes apparently no sense within a Darwinian framework. At face value, language as we can observe it should never have existed or should have been counter-selected. In other words, the selection pressure that led to language is still missing. The solution I propose consists in regarding language as a social signaling device that developed in a context of generalized insecurity that is unique to our species. By talking, individuals advertise their alertness and their ability to get informed. This hypothesis is shown to be compatible with many characteristics of language that otherwise are left unexplained.

Individuals devote one third of their language time to mentioning unexpected events. We try to make sense of this universal behaviour within the Costly Signalling framework. By systematically using language to point to the unexpected, individuals send a signal that advertises their ability to anticipate danger. This shift in display behaviour, as compared with typical displays in primate species, may result from the use by hominins of artefacts to kill.

Selection through iterated learning explains no more than other non-functional accounts, such as Universal Grammar (UG), why language is so well designed for communicative efficiency. It does not predict several distinctive features of language, such as central embedding, large lexicons, or the lack of iconicity, which seem to serve communication purposes at the expense of learnability.

The fact that human beings universally put much energy and conviction in reporting events in daily conversations demands an explanation. After having observed that the selection of reportable events is based on unexpectedness and emotion, we make a few suggestions to show how the existence of narrative behaviour can be consistent with the socio-political theory of the origin of language.

A modular analysis of spontaneous language use provides support for the existence of an identifiable step in language evolution, protolanguage. Our suggestion is that a grammarless form of expression would have evolved to signal unexpected events, a behavior still prevalent in our species. Words could not be so specific as to refer to whole, non-recurring, situations. They referred to elements such as objects or locations, and the communicated event was inferred metonymically. Compositionality was achieved, without syntax, through multi-metonymy, as words referring to elements of the same situation were concatenated into proto-utterances.

Jean-Louis Dessalles explores the co-evolutionary paths of biology, culture, and the great human edifice of language, linking the evolution of the language to the general evolutionary history of humankind. He provides searchingly original answers to such fundamental paradoxes as to whether we acquired our greatest gift in order to talk or so as to be able to think, and as to why human beings should, as experience constantly confirms, contribute information for the well-being of others at their own expense and for no apparent gain: which if this is one of language's main functions appears to make its possession, in Darwinian terms, a disadvantage. Dr Dessalles looks for solutions in the early history of human species and considers the degree to which language evolved as a means of choosing profitable coalition partners and maximizing individual success within a competitive social environment.

The author opens with a discussion of the differences between animal and human communication and the biological foundations of language. He looks at the physiological preconditions for language evolution and the early evolution of meaning and communication. He then embarks on an important and original account of the natural history of conversation. Here he considers the roles of language in supporting social cohesion and information exchange.

This challenging and original account will appeal to all those interested in the origins of language and the evolution of human behaviour.

Table of Contents

Part I The Place of Language in Human Evolutionary History
1. Animal and Human Communication
2. Culture, Languages, and Language
3. The Biological Roots of Language
4. Misapprehensions about the Origins of Language
5. Language as an Evolutionary Curiosity
6. The Local Optimality of Language
Part II The Functional Anatomy of Speech
7. Putting Sounds Together
8. Protolanguage
9. The Mechanics of Syntax
10. Syntax and Meaning
11. The Structure of Meanings
12. The Emergence of Meaning
Part III The Ethology of Language
13. Conversation Behaviour
14. Language as Information
15. The Birth of Argumentation
16. Language as an Evolutionary Paradox
17. The Political Origins of Language
18. Epilogue

The systematic and universal communicative behaviour that drives human beings to give honest information to conspecifics during long-lasting conversational episodes still represents a Darwinian paradox. Attempts to solve it by comparing conversation with a mere reciprocal cooperative information exchange is at odds with the reality of spontaneous language use. The Costly Signalling Theory has recently attracted attention as a tentative explanation of the evolutionary stability of language. Unfortunately, it makes the wrong prediction that only elite individuals would talk. I show that as far as social bonding is assortative in our species, generalised signalling through language becomes a viable strategy to attract allies.

Language is the main distinctive feature of our species. Why do we feel the urge to communicate with our fellows, and why is this form of communication, characterised by relevance, unique in animal kingdom ? In this chapter, we will first stress this specificity of human communication. In a second part, using computer evolutionary simulations, we will dismiss the usual claim that human communication is a specific form of reciprocal cooperation. A Darwinian account of language requires that we find a selective advantage in the communication act. We will propose, in the third part of this chapter, that such an advantage can be found if we consider language activity in the broader frame of human social organisation. In the continuation of the 'chimpanzee politics' studied by de Waal (1982), the ability to form large coalitions must have been an essential feature of hominid societies (Dunbar 1996). We will suggest that relevant speech originated in this context, as a way for individuals to select each other to form alliances.

Animal behavior is often altruistic. In the frame of the theory of natural selection, altruism can only exist under specific conditions like kin selection or reciprocal cooperation. We show that reciprocal cooperation, which is generally invoked to explain non-kin altruism, requires very restrictive conditions to be evolutionary stable. Some of these conditions are not met in many cases of altruism observed in nature. In the search of another explanation of non-kin altruism, we consider Zahavis's theory of prestige. We extend it to propose a 'political' model of altruism. We give evidence showing that non-kin altruism can evolve in the context of inter-subgroup competition. Under such circumstances, altruistic behavior can be used by individuals to advertise their quality as efficient coalition members. In this model, only abilities which positively correlate with the subgroup success can evolve into altruistic behaviors.

We deal here with the problem of the origin of language from the point of view of pragmatics. Our aim is to show that any scenario of language origin should explain the relevance phenomenon. Why do people feel obliged to be relevant in casual conversation ? Analysing the structure of relevance leads to unexpected conclusions : relevant information is valuable, therefore language seems to be altruistic. As a consequence, from a Darwinian perspective, speakers should be rare and continually prompted for their knowledge. What we observe, however, is the exact opposite : in many situations, speakers repeatedly strive to make their point, while listeners systematically evaluate what they hear. A possible solution to this paradox is that language is not altruistic and that relevant information is traded for status. The observation of spontaneous conversation provides some evidence that supports such a hypothesis.