Cultural specialization as a double-edged sword: division into specialized guilds might promote cultural complexity at the cost of higher susceptibility to cultural loss

Abstract

The transition to specialization of knowledge within populations could have facilitated the accumulation of cultural complexity in humans. Specialization allows populations to increase their cultural repertoire without requiring that members of that population increase their individual capacity to accumulate knowledge. However, specialization also means that domain-specific knowledge can be concentrated in small subsets of the population, making it more susceptible to loss. Here, we use a model of cultural evolution to demonstrate that specialized populations can be more sensitive to stochastic loss of knowledge than populations without subdivision of knowledge, and that demographic and environmental changes have an amplified effect on populations with knowledge specialization. Finally, we suggest that specialization can be a double-edged sword; specialized populations may have an advantage in accumulating cultural traits but may also be less likely to expand and establish themselves successfully in new demes owing to the increased cultural loss that they experience during the population bottlenecks that often characterize such expansions. This article is part of the theme issue ‘Human socio-cultural evolution in light of evolutionary transitions’.

Human socio-cultural evolution in light of evolutionary transitions: introduction to the theme issue

“…Specialization has been often mentioned as a driver of ETIs. In this context, Ben-Oren et al [31] discuss the role of specialization in humans. They demonstrate that while specialization can increase a population's cultural repertoire it may also make it less resilient to population bottlenecks.…”

Human major transitions from the perspective of distributed adaptations

“…The cultural repertoire of modern societies is vast, and even merely its aspects that are related to technology cannot be manifested by any single individual. DAs in the form of cultural specialization into professional guilds, in the sense that knowledge is partitioned among different subgroups within society, seems to have been common in societies after the Neolithic revolution [38][39][40][41][42][43][44][45]; importantly, and although often less obvious to an external observer, there are clear examples of such distribution of knowledge also in huntergatherer societies, even though many of them are overall fairly generalist in the sense that most individuals can carry out most technological tasks [39,[46][47][48][49][50]. An interesting example of distribution of crucially adaptive information developed among some groups of Aboriginal huntergatherers in Australia [51][52][53] regarding information about the lay of the land.…”

“…If successful establishment in a certain habitat required certain DAs, or if human populations grew to rely on DAs, extreme environmental conditions that set a low population carrying capacity might have prevented colonization for significant periods of time in certain regions such as the Siberian Arctic [ 61 ]. Alternatively, they might have allowed only certain human cultures and not others to establish in places whose colonization required passage through a population bottleneck: a population with minimal reliance on DAs may be better adapted to colonization of new regions [ 45 ].…”

“…The DA perspective suggests an additional factor that may have played a role: early hunter–gatherers may have been able to migrate to Australia through extreme bottlenecks without losing a substantial part of their cultural repertoire. However, if later societies that attempted to settle in Australia were reliant more heavily on DAs, for example in the form of a much larger technological toolkit and more extensive cultural knowledge to support their subsistence pattern, they would have needed to migrate in much larger numbers to be able to sustain their culture [ 45 ]. Such migration in large numbers was not feasible until the development of advanced sailing techniques in recent millennia.…”

Modelling effects of inter-group contact on links between population size and cultural complexity

“…Different mechanisms can contribute to such an effect: for a given per capita innovation rate, large groups will invent more tools simply because they contain more innovators. Further, the presence of more learners can also reduce tool loss, facilitating cultural accumulation; smaller populations are at higher risk of losing technologies because fewer individuals know each tool [ 4 , 18 ]. Additionally, contact between groups may allow for the combination of cultural features (as explored in [ 8 ]), which may also increase the cultural repertoire.…”