In primate societies, and different from members of social insect societies, an individual is not only socially situated (being part of and surrounded by a social environment) but also socially embedded [ED98] which means that the agent needs to pay attention to other agents and their interactions individually. Particularly human primates are specialized in predicting, manipulating and dealing with highly complex social dynamics (involving direct relationships as well as third-party relationships); they possess language as an effective means of preserving group coherence, `social grooming' [Dun93], and communicate about themselves and others in terms of stories [Dau99b]. Humans are not only dealing with very complex relationships but seem to have mental `models' of themselves, others and the social world (cf. [Whi91], [BC95]). Humans, different from social insects live in individualized societies (as do some other species of birds and mammals). An increasingly complex social field and an increasing need to effectively communicate with each other were likely to have been among the important constraints in the evolution of human minds.
Minds are certainly attributed to members of Homo sapiens (and as some evidence suggests several other hominid species might have existed with `minds'), but other candidates exist among mammals (e.g. non-human apes, dolphins, elephants) and birds (e.g. parrots and members of the crow family). Interestingly, species which we describe as possessing a `mind' are all highly social. Even the `solitary' life style of Pongo pygmaeus or orangutans, (who nevertheless seem to be highly social in their ability to recognise and interact with each other) is rather a secondary adaptation to a particular environment which demands a spatially `distributed' social organization. The Social Intelligence Hypothesis suggests that primate intelligence primarily evolved in adaptation to social complexity, i.e. in order to interpret, predict and manipulate conspecifics (see overview in [BW88]). Thus, there are two interesting aspects to human sociality: it served as an evolutionary constraint which led to an increase of brain size in primates, this in return led to an increased capacity to further develop social complexity.
Although it is still unknown why hominids needed or chose to live in social groups, this feedback principle soon led to the development of highly sophisticated levels of organization and control in human societies. In [Rus93] four levels of social organization are discussed which might serve as models for the evolution of primate societies: a) the `shrew'-type pre-primates: solitary, many offspring, insectivores, e.g. Purgatorius, a 70-million-year-old fossil, b) the `mouse-lemur'-type primates: bush-living, nocturnal, strong mother-daughter bonding (stable matrilines), social learning (offspring learns from mother), solitary males and social groups of mothers and daughters, e.g. the 50-million-year-old fossil Shoshonius cooperi, c) the `Lemur catta'-type diurnal lemurs: appearing about 54 million years ago, social groups (troops), dominant females, submissive males, stable matrilines, occasionally consort bonds between single male and female, e.g. Adapidae, d) the `chimpanzee'-type lemur-ape: appearing about 24 million years ago, groups of dominant males and submissive females, stable families of mothers and their offspring, male power coalitions, e.g. Dryopithecus. The social organization of recent species of apes shows variations of this pattern: of harem-structures (gorilla), solitary lifestyle (orangutan). Such stages of social organization can be related to behavioral as well as cognitive capacities of primates.
The terms `theory of mind' and mindreading are usually used in order to discuss whether an animal is able to reflect on its own mental states (e.g. desires, intentions and beliefs) and those of others. Researchers have studied whether humans might have particularly specialized in a theory of mind [PW78], [PP95]. However, as Richard Byrne pointed out [Byr97], the Social Intelligence Hypothesis might account for the evolution of primate intelligence, but not for the specific human kind of intelligence. Here, narrative psychology and studies on the development of autobiographic memory and a `self' might offer an explanation: evidence suggests that `stories' are the most efficient and natural human way to communicate, in particular to communicate about others [Bru91]. The Narrative Intelligence Hypothesis [Dau99a] proposes that the evolutionary origin of communicating in stories was correlated with increasing social dynamics among our human ancestors, in particular the necessity to communicate about third-party relationships (which in humans reaches the highest degree of sophistication among all apes, cf. gossip).