Trivers, R. L. Am. Zool. 14, 249–264 (1974).
Clutton-Brock, T. H. The Evolution of Parental Care (Princeton University Press, Princeton, 1991).
Perrins, C. M. J. Anim. Ecol. 34, 601–647 (1965).
Trivers, R. L. & Hare, H. Science 191, 249–263 (1976).
Hamilton, W. D. J. theor. Biol. 7, 1–16, 17–52 (1964).
Parker, G. A. & Macnair, M. R. Anim. Behav. 27, 1210–1235 (1979).
Stamps, J. A., Metcalf, R. A. & Krishman, V. V. Behavl Ecol. Sociobiol. 3, 367–392 (1978).
Feldman, M. W. & Eshel, I. Am. Nat. 119, 285–292 (1982).
Parker, G. A. Anim. Behav. 33, 519–533 (1985).
Hussell, D. J. T. Am. Nat. 131, 175–202 (1988).
Esnel, I. & Feldman, M. W. Am. Nat. 137, 167–185 (1991).
Harper, A. B. Am. Nat. 128, 99–114 (1986).
Grafen, A. J. theor. Biol. 144, 473–516 (1990).
Grafen, A. J. theor. Biol. 144, 517–546 (1990).
Zahavi, A. J. theor. Biol. 53, 205–214 (1975).
Enquist, M. Anim. Behav. 33, 1152–1161 (1985).
Parker, G. A. in Mate Choice (ed. Bateson, P.) 141–166 (Cambridge University Press, Cambridge, 1983).
Maynard Smith, J. Evolution and the Theory of Games (Cambridge University Press, Cambridge, 1982).
Queller, D. C. Oxford Sun. evol. Biol. 6, 73–109 (1989).
Godfray, H. C. J. & Parker, G. A. Anim. Behav. (in the press).
Godfray, H. C. J. & Parker, G. A. Phil. Trans. R. Soc. B 332, 67–79 (1991).
Dawkins, M. S. & Guilford, T. Anim. Behav. 41, 865–874 (1991).
Johnstone, R. & Grafen, A. J. theor. Biol. (in the press).
Maynard Smith, J. Anim. Behav. (in the press).
Alexander, R. D. A. Rev. Ecol. Syst. 5, 325–383 (1974).
