[1] J. R. Hurford. Biological evolution of the saussurean sign as a component of the language acquistion device. Lingua, 1989.

[2] S. Pinker and P. Bloom. Natural language and natural selection. Behavioral and Brain Sciences, 13:707--784, 1990.

[3] M. Oliphant. The dilemma of Saussurean communication. 37:31--38, 1996.

[4] J. Maynard Smith and E. Szathm’ary. The Major Transitions in Evolution. Oxford University Press, 1997.

[5] A. Rubinstein. Economics and Language. Cambridge University Press, 2000.

[6] M. A. Nowak and D. C. Krakauer. The evolution of language. Proceedings of the National Academy of Sciences USA, 96:8028--8033, 1999.

[7] M. A. Nowak, J. B. Plotkin, and D. C. Krakauer. The evolutionary language game. Journal of Theoretical Biology, 200:147--162, 1999.

[8] M. A. Nowak, J. B. Plotkin, and V. A. A. Jansen. The evolution of syntactic communication. Nature, 404:495--498, 2000.

[9] M. A. Nowak, N. L. Komarova, and P. Niyogi. Evolution of universal grammar. Science, 291:114--118, 2001.

[10] S. Pinker. Survival of the clearest. Nature, 404:441--442, 2000. 28

[11] C. Knight. Ritual/speech coevolution: a solution to the problem of deception. page 68. 1998.

[12] A. Zahavi. Mate selection a selection for a handicap. Journal of Theoretical Biology, 53:205--214, 1975.

[13] A. Grafen. Biological signals as handicaps. Journal of Theoretical Biology, 144:517--546, 1990.

[14] J. Maynard Smith. Honest signalling: The Philip Sidney game. Animal Behaviour, 42:1034--1035, 1991.

[15] H. C. J. Godfray. Signalling of need by o#spring to their parents. 352:328--330, 1991.

[16] O. Hasson. Cheating signals. Journal of Theoretical Biology, 167:223-238, 1994.

[17] O. Hasson. Towards a general theory of biological signaling. Journal of Theoretical Biology, 185(2):139--156, 1997.

[18] J. Maynard Smith and D. G. C. Harper. Animal signals: Models and terminology. Journal of Theoretical Biology, 177:305--311, 1995.

[19] C. T. Bergstrom and M. Lachmann. Signalling among relatives. III. Talk is cheap. Proceedings of the National Academy of Sciences USA, 95:5100--5105, 1998.

[20] Sz. Sz’amad’o. Cheating as a mixed strategy in a simple model of aggressive communication. Animal Behaviour, 59:221. 29

[21] A. Zahavi. The cost of honesty (Further remarks on the handicap principle). Journal of Theoretical Biology, 67:603--605, 1977.

[22] N. Nur and O. Hasson. Phenotypic plasticity and the handicap principle. Journal of Theoretical Biology, 110:275--297, 1984.

[23] R. A. Johnstone and A. Grafen. The continuous Sir Philip Sidney game: A simple model of biological signalling. Journal of Theoretical Biology, 156:215--234, 1992.

[24] J. Maynard Smith. Must reliable signals always be costly? Animal Behaviour, 47:1115--1120, 1994.

[25] S. Rohwer. The evolution of reliable and unreliable badges of fighting ability. American Zoologist, 22:531--546, 1982.

[26] M. Enquist. Communication during aggressive interactions with particular reference to variation in choice of behaviour. Animal Behaviour, 33:1152--1161, 1985.

[27] J. Maynard Smith and D. G. C. Harper. The evolution of aggression: can selection generate variability? Philosophical Transactions of the Royal Society of London, Series B, 319:557--570, 1988.

[28] H. Viljugrein. The cost of dishonesty. Proceedings of the Royal Society of London Series B, 264(1383):815--821, 1997.

[29] J. B. Silk, E. Kaldor, and R. Boyd. Cheap talk when interests conflict. Animal Behaviour, 59:423--432, 2000. 30

[30] T. Guilford and M. S. Dawkins. What are conventional signals? Animal Behaviour, 49:1689--1695, 1995.

[31] A. Zahavi. On the defination of sexual selection, fisher's model, and the evolution of waste and of signals in general. Animal Behaviour, 42:501--503, 1991.

[32] A. Zahavi. A reply to John. Animal Behaviour, 54:228--229, 1997.

[33] T. Getty. Handicap signalling: when fecundity and viability do not add up. Animal Behaviour, 56:127--130, 1998.

[34] P. L. Hurd. Communication in discrete action-response games. Journal of Theoretical Biology, 174(2):217--222, 1995.

[35] M. Lachmann, C. T. Bergstrom, and S. Szamado. The death of costly signalling? Santa Fe Institute Working Paper Series, (00-12-072), 2000. http://www.santafe.edu/sfi/publications/working-papers.html.

[36] S. Rohwer. The social significance of avian winter plumage variability. Evolution, 29:593--610, 1975.

[37] D. P. Whitfield. Plumagve variability, status signalling and individual recognition in avian flocks. Trends in Ecology and Evolution, 2:13--18, 1987.

[38] S. Rohwer. Status signaling in harris sparrows: Some experiments in deception. Behavior, 61:107--129, 1975.

[39] S. Rohwer and F. C. Rohwer. Status signals in Harris' sparrows: experimental deceptions achieved. Animal Behaviour, 26:1012--1022, 1978. 31

[40] A. P. Moller. Social control of deception among status signalling house sparrows Passer domesticus. Behavioral Ecology and Sociobiology, 20:307--311, 1987.

[41] G. E. Hill. Trait elaboration via adaptive mate choice: sexual conflict in the evolution of signals of male quality. Ethology Ecology and Evolution, 6:351--370, 1994.

[42] H. C. J. Godfray. Evolutionary theory of parent-o#spring conflict. 376:133--138, 1995.

[43] S. Pinker. The Language Instinct. Harper, 1995.

[44] M. Lachmann and C. T. Bergstrom. Signalling among relatives. II. Beyond the Tower of Babel. Theoretical Population Biology, 54:146-160, 1998.

[45] N. C. Grassly, A. von Haeseler, and D. C. Krakauer. Error, population structure, and the origin of diverse sign systems. Journal of Theoretical Biology, 206:369--378, 2000.

[46] T. Veblen. The Theory of the Leisure Class. Dover Publications, Mineola, N.Y., 1889.

[47] N. Chomsky. Rules and representations. Columbia University Press, New York, 1980.

[48] D. Bickerton. Language and species. University of Chicago Press, Chicago, 1990. 32