Abstract
Primates have unusually large brains for body size compared to all other vertebrates. Over the years, a number of explanations have been offered for this, leading to some confusion. I use a systems approach to make sense of these suggestions, and this suggests that some are constraints (energetic or neural development explanations), others consequences (generated by windows of opportunity), but only the social hypotheses constitute the real selective pressure for the evolution of brains. The social hypotheses come in two current forms (bonding social groups vs. social learning of foraging skills) that differ in whether predation or food-finding are assumed to be the rate-limiting factor in primate survival. While the standard form of the social brain hypothesis in primates is a quantitative relationship between social group size and brain size, comparative analyses for other mammal and bird taxa reveal that it takes a purely qualitative (i.e., categorical) form in all nonprimates examined so far: species with pairbonded (i.e., monogamous) mating systems have larger brains than all others. I suggest that this difference is due to the fact that anthropoid primates developed bonded social systems early in their evolutionary history. Finally, I consider briefly the implications of these findings for human evolutionary history.
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References
Abbott DH, Keverne EB, Moore GF, Yodyinguad U (1986) Social suppression of reproduction in subordinate talapoin monkeys, Miopithecus talapoin. In: Else JG, Lee PC (eds) Primate ontogeny, cognition, and social behaviour. Cambridge University Press, Cambridge, pp 329–341
Adamczak V, Dunbar RIM (2008) Variation in the mating system of oribis and its ecological determinants. Afr J Ecol 45:197–206
Aiello LC, Dunbar RIM (1993) Neocortex size, group size and the evolution of language. Curr Anthropol 34:184–193
Aiello LC, Wheeler P (1995) The expensive-tissue hypothesis: the brain and the digestive system in human and primate evolution. Curr Anthropol 36:199–221
Altmann SA (1998) Foraging for survival. University of Chicago Press, Chicago
Armstrong E, Bergeron R (1985) Relative brain size and metabolism in birds. Brain Behav Evol 26:141–153
Barrickman NL, Bastian ML, Isler K, van Schaik CP (2008) Life history costs and benefits of encephalization: a comparative test using data from long-term studies of primates in the wild. J Hum Evol 54:568–590
Barton RA (1996) Neocortex size and behavioural ecology in primates. Proc Roy Soc Lond B 263:173–177
Barton RA (1998) Visual specialization and brain evolution in primates. Proc Roy Soc Lond B 265:1933–1937
Barton RA, Dunbar RIM (1997) Evolution of the social brain. In: Whiten A, Byrne RW (eds) Machiavellian intelligence II: extensions and evaluations. Cambridge University Press, Cambridge, pp 240–263
Bergman TJ, Beehner JC, Cheney DL, Seyfarth RM (2003) Hierarchical classification by rank and kinship in baboons. Science 302:1234–1236
Buys CJ, Larsen KL (1979) Human sympathy groups. Psychol Rep 45:547–553
Byrne RW, Corp N (2004) Neocortex size predicts deception rate in primates. Proc Roy Soc Lond B 271:1693–1699
Byrne RW, Whiten A (1988) Machiavellian intelligence. Oxford University Press, Oxford
Calhim S, Shi J, Dunbar RIM (2006) Sexual segregation among feral goats: testing between alternative hypotheses. Anim Behav 72:31–41
Charnov EL (1993) Life history invariants. Oxford University Press, Oxford
Charnov EL, Berrigan D (1993) Why do female primates have such long lifespans and so few babies? Or life in the slow lane. Evol Anthropol 2:191–194
Cheney DL, Seyfarth RM (1999) Recognition of other individuals’ social relationships by female baboons. Anim Behav 58:67–75
Cheney DL, Seyfarth RM (2007) Baboon metaphysics: the evolution of a social mind. University of Chicago Press, Chicago
Clutton-Brock TH (1988) Reproductive success: studies of individual variation in contrasting breeding systems. University of Chicago Press, Chicago
Clutton-Brock TH, Harvey PH (1980) Primates, brains and ecology. J Zool Lond 190:309–323
Datta SB (1983) Relative power and the maintenance of dominance. In: Hinde RA (ed) Primate social relationships: an integrated approach. Blackwell, Oxford, pp 103–112
Deaner RO, Nunn CL, van Schaik CP (2000) Comparative tests of primate cognition: different scaling methods produce different results. Brain Behav Evol 55:44–52
Dunbar RIM (1980) Determinants and evolutionary consequences of dominance among female gelada baboons. Behav Ecol Sociobiol 7:253–265
Dunbar RIM (1984) Reproductive decisions: an economic analysis of gelada baboon social strategies. Princeton University Press, Princeton, NJ
Dunbar RIM (1987) Habitat quality, population dynamics and group composition in colobus monkeys (Colobus guereza). Int J Primatol 8:299–329
Dunbar RIM (1988) Primate social systems. Chapman & Hall, London
Dunbar RIM (1989) Reproductive strategies of female gelada baboons. In: Rasa AE, Vogel C, Voland E (eds) The sociobiology of sexual and reproductive strategies. Chapman & Hall, London, pp 74–92
Dunbar RIM (1991) Functional significance of social grooming in primates. Folia Primatol 57:121–131
Dunbar RIM (1992) Neocortex size as a constraint on group size in primates. J Hum Evol 22:469–493
Dunbar RIM (1993) Coevolution of neocortex size, group size and language in humans. Behav Brain Sci 16:681–735
Dunbar RIM (1996) Grooming, gossip and the evolution of language. Faber & Faber, London
Dunbar RIM (1998) The social brain hypothesis. Evol Anthropol 6:178–190
Dunbar RIM (2003) Evolution of the social brain. Science 302:1160–1161
Dunbar RIM (2004) The human story: a new history of mankind’s evolution. Faber & Faber, London
Dunbar RIM, Dunbar EP (1977) Dominance and reproductive success among female gelada baboons. Nature 266:351–352
Dunbar RIM, Shultz S (2007a) Understanding primate brain evolution. Phil Trans Roy Soc B 362:649–658
Dunbar RIM, Shultz S (2007b) Evolution in the social brain. Science 317:1344–1347
Dunbar RIM, Cornah L, Daly F, Bowyer K (2002) Vigilance in humans: a test of alternative hypotheses. Behaviour 139:695–711
Dunbar RIM, Gamble C, Gowlett JAG. Human evolution and the archaeology of the social brain. Curr Anthropol (in press)
Finlay BL, Darlington RB (1995) Linked regularities in the development and evolution of mammalian brains. Science 268:1578–1584
Finlay BL, Darlington RB, Nicastro N (2001) Developmental structure in brain evolution. Behav Brain Sci 24:263–308
Gibson KR (1986) Cognition, brain size and the extraction of embedded food resources. In: Else JG, Lee PC (eds) Primate ontogeny, cognition and social behaviour. Cambridge University Press, Cambridge, pp 93–104
Hamilton MJ, Milne BT, Walker RS, Burger O, Brown JH (2007) The complex structure of hunter-gatherer social networks. Proc Roy Soc Lond B 274:2195–2202
Hill RA, Bentley RA, Dunbar RIM (2008) Network scaling reveals consistent fractal pattern in hierarchical mammalian societies. Biol Lett 4:748–751
Hofman MA (1983) Energy metabolism, brain size and longevity in mammals. Q Rev Biol 58:495–512
Isler K, van Schaik CP (2006) Metabolic costs of brain size evolution. Biol Lett 2:557–560
Jerison HJ (1973) Evolution of the brain and intelligence. Academic Press, London
Karbowski J (2007) Global and regional brain metabolic scaling and its functional consequences. BMC Biol 5:18. doi:10.1186/1741-7007-5-18
Kaufman JA (2003) On the expensive tissue hypothesis: independent support from highly encephalized fish. Curr Anthropol 44:705–706
Kudo H, Dunbar RIM (2001) Neocortex size and social network size in primates. Anim Behav 62:711–722
Lehmann J, Korstjens AH, Dunbar RIM (2007a) Group size, grooming and social cohesion in primates. Anim Behav 74:1617–1629
Lehmann J, Korstjens AH, Dunbar RIM (2007b) Fission–fusion social systems as a strategy for coping with ecological constraints: a primate case. Evol Ecol 21:613–634
Lehmann J, Korstjens AH, Dunbar RIM (2008a) Time management in great apes: implications for gorilla biogeography. Evol Ecol Res 10:517–536
Lehmann J, Korstjens AH, Dunbar RIM (2008b) Time and distribution: a model of ape biogeography. Ethol Ecol Evol 20:337–359
Lehmann J, Andrews K, Dunbar RIM (in press). Social networks and social complexity in female-bonded primates. In: Dunbar RIM, Gamble C, Gowlett JAG (eds) Social Brain, Distributed Mind. Oxford University Press, Oxford
Lewis KP (2000) A comparative study of primate play behaviour: implications for the study of cognition. Folia Primatol 71:417–421
Martin RD (1981) Relative brain size and basal metabolic rate in terrestrial vertebrates. Nature 293:57–60
Mink JW, Blumenschine RJ, Adams DB (1981) Ratio of central nervous system to body metabolism in vertebrates – its constancy and functional basis. Am J Physiol 241:R203–R212
Nettle D (1999) Linguistic diversity. Oxford University Press, Oxford
Pagel MD (1997) Inferring evolutionary processes from phylogenies. Zool Scr 26:331–348
Parker ST, Gibson KR (1979) A developmental model for the evolution of language and intelligence in early hominids. Behav Brain Sci 2:367–408
Pawłowski BP, Lowen CB, Dunbar RIM (1998) Neocortex size, social skills and mating success in primates. Behaviour 135:357–368
Pérez-BarberÃa FJ, Shultz S, Dunbar RIM (2007) Evidence for coevolution of sociality and relative brain size in three orders of mammals. Evolution 61:2811–2821
Reader SM, Laland KN (2002) Social intelligence, innovation and enhanced brain size in primates. Proc Natl Acad Sci USA 99:4436–4441
Shultz S, Dunbar RIM (2006) Chimpanzee and felid diet composition is influenced by prey brain size. Biol Lett 2:505–508
Shultz S, Dunbar RIM (2007) The evolution of the social brain: anthropoid primates contrast with other vertebrates. Proc Roy Soc Lond B 274:2429–2436
Shultz S, Noë R, McGraw WS, Dunbar RIM (2004) A community-level evaluation of the impact of prey behavioural and ecological characteristics on predator diet composition. Proc Roy Soc Lond B 271:725–732
Shultz S, Bradbury RB, Evans KL, Gregory RD, Blackburn TM (2005) Brain size and resource specialisation predict long-term population trends in British birds. Proc Roy Soc Lond B 272:2305–2311
Sol D, Timmermans S, Lefebvre L (2002) Behavioural flexibility and invasion success in birds. Anim Behav 63:495–502
Sol D, Duncan RP, Blackburn TM, Cassey P, Lefebrve L (2005) Big brains, enhanced cognition and response of birds to novel environments. Proc Natl Acad Sci USA 102:5460–5465
van Schaik CP (1983) Why are diurnal primates living in groups. Behaviour 87:120–144
van Schaik CP (1989) The ecology of social relationships amongst female primates. In: Standen V, Foley RA (eds) Comparative socioecology: the behavioral ecology of humans and other mammals. Blackwell, Oxford, pp 195–218
van Schaik CP, Dunbar RIM (1990) The evolution of monogamy in large primates: a new hypothesis and some crucial tests. Behaviour 115:30–62
Wittig RM, Crockford C, Lehmann J, Whitten PL, Seyfarth RM, Cheney DL (2008) Focused grooming networks and stress alleviation in wild female baboons. Horm Behav 54:170–177
Zhou W-X, Sornette D, Hill RA, Dunbar RIM (2005) Discrete hierarchical organization of social group sizes. Proc Roy Soc Lond B 272:439–444
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Dunbar, R.I.M. (2010). Brain and Behaviour in Primate Evolution. In: Kappeler, P., Silk, J. (eds) Mind the Gap. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-02725-3_15
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