Coevolution of neocortical size, group size and language in humans

@article{Dunbar1993CoevolutionON,
  title={Coevolution of neocortical size, group size and language in humans},
  author={Robin I. M. Dunbar},
  journal={Behavioral and Brain Sciences},
  year={1993},
  volume={16},
  pages={681 - 694}
}
  • Robin I. M. Dunbar
  • Published 1 December 1993
  • Psychology, Biology
  • Behavioral and Brain Sciences
Abstract Group size covaries with relative neocortical volume in nonhuman primates. This regression equation predicts a group size for modern humans very similar to that for hunter-gatherer and traditional horticulturalist societies. Similar group sizes are found in other contemporary and historical societies. Nonhuman primates maintain group cohesion through social grooming; among the Old World monkeys and apes, social grooming time is linearly related to group size. Maintaining stability of… 
What about the increasing adaptive value of manipulative language use. Author's response
Group size covaries with relative neocortical volume in nonhuman primates. This regression equation predicts a group size for modern humans very similar to that for hunter-gatherer and traditional
Neocortex size and social network size in primates
TLDR
It is shown that, in respect of neocortex size, there are as many as four statistically distinct grades within the primates (including humans), and analysis of the patterns of grooming among males and females suggested that large primate social groups often consist of a set of smaller female subgroups that are linked by individual males.
Discrete hierarchical organization of social group sizes
TLDR
This study combines data on human grouping patterns in a comprehensive and systematic study and identifies a discrete hierarchy of group sizes with a preferred scaling ratio close to three, which could reflect a hierarchical processing of social nearness by human brains.
Neocortex size predicts deception rate in primates
  • R. Byrne, N. Corp
  • Biology, Psychology
    Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 2004
TLDR
It is shown that the use of deception within the primates is well predicted by the neocortical volume, when observer effort is controlled for; by contrast, neither the size of the rest of the brain nor the group size exert significant effects.
Social complexity and the fractal structure of group size in primate social evolution
TLDR
It is argued that the grades themselves represent glass ceilings on animals' capacity to maintain social and spatial coherence during foraging and that, in order to evolve more highly bonded groups, species have to be able to invest in costly forms of cognition.
Social Brain Hypothesis: Vocal and Gesture Networks of Wild Chimpanzees
TLDR
The results suggest that in addition to grooming, both gestures and synchronized vocalizations may play key roles in allowing chimpanzees to manage a large and differentiated set of social relationships.
Gestural repertoire size is associated with social proximity measures in wild chimpanzees
TLDR
Results suggest that gestural repertoire size has important implications for maintaining social relationships in wild chimpanzees and more broadly that Gestural communication may have played an important role in language evolution.
Dunbar's number: group size and brain physiology in humans reexamined.
TLDR
Cross-cultural comparison of not only group size but also relationship-reckoning systems like kinship terminologies suggests that although neocortices are undoubtedly crucial to human behavior, they cannot be given such primacy in explaining complex group composition, formation, or management.
Group size, grooming and social cohesion in primates
The Social Brain
The social-brain hypothesis refers to a quantitative relationship between social-group size and neocortex volume in monkeys and apes. This relationship predicts a group size of approximately 150 for
...
...

References

SHOWING 1-10 OF 274 REFERENCES
The size of the neocortex in relation to ecology and social structure in monkeys and apes.
  • T. Sawaguchi
  • Biology
    Folia primatologica; international journal of primatology
  • 1992
TLDR
It is found that RSNs are related to diet and social structure: frugivorous anthropoids had higher values of R SNs than folivorous Anthropoids, and polygynous anthropoid had significantly higher values than monogynous anthropoids.
The similarity principle underlying social bonding among female rhesus monkeys.
TLDR
A simpler, more encompassing principle underlying interfemale attraction is proposed, according to which rhesus females establish bonds with females whom they most resemble, which is based on multivariate analyses and a comparison of theoretical models.
Why Are Diurnal Primates Living in Groups
TLDR
A critical test is proposed of the hypothesis that increasing group size should lead to reduced predation risk by comparing demographic patterns between areas where predators are still present and where they have disappeared and the results provide strong support for the predation-feeding competition theory.
Lemur Social Behavior and Primate Intelligence
TLDR
It seems likely that the rudiments of primate society preceded the growth ofPrimate intelligence, made it possible, and determined its nature.
On the evolution of Ape Social Systems
Despite theoretical advances in understanding the nature of social evolution (e.g. Hamilton, 1964; Trivers, 1972) a clear procedure for analysing the adaptive functions of social life has not yet
Language capacities of nonhuman animals
TLDR
This paper reviews the language analogue studies with great apes and cetaceans, examining the utility of the different methods and reviewing the animals' accomplishments, and concluding that chimpanzees and bonobos do not threaten human uniqueness with respect to speech and language.
Gyrification in the cerebral cortex of primates.
TLDR
Paleontological studies of total sulcal length can give direct information on the evolution of cortical folding in primates and the best predictor for convolutedness in anthropoids is neocortical volume, while in prosimians it is brain weight.
Social and non-social knowledge in vervet monkeys
The social knowledge of East African vervet monkeys is striking. W ithin a local population the monkeys recognize individuals, and associate each individual with its particular group. W ithin groups,
...
...