“One reason for this debate has been the reluctance of archaeologists, for natural reasons, to date capacities tied to a certain technology as older than the oldest finds of that technology. But evolutionary methodology makes it possible to draw the conclusion that the capacities necessary for cultural development must be older than the first finds in Europe”, says Kerstin Lidén, Professor of Archaeology and one of the researchers involved in the study.

 
Kulturella förmågor. Foto: Johan Lind
Cultural capacities. Photo: Johan Lind
 

“The basic reasoning is really straightforward. It is simply not possible to date the capacity to solve Rubik’s Cube by dating the appearance of Rubik’s Cube in human history. Because we know that people from all around the world can learn to read and write, these capabilities cannot have evolved long after the origin of our species, if there are no later signs of a genetic basis for these capacities spreading to all corners of the earth”, says Johan Lind, who lead the study.

This is one of the central conclusions that points to cultural capacities as having evolved earlier than 170,000 years ago; it must have occurred before the first split of the modern human lineage into different groups.

Chance and population size affects cultural evolution

But this find leads to another riddle. If human cultural capacity is at least 170,000 years old, why didn’t for example agriculture emerge until 12,000 years ago and why was writing invented as late as 5,600 years ago? The lag is probably explained by the idea that it can take a long time to develop advanced culture. Mathematical models illustrate how the evolution of culture is affected by both stochasticity and population size.

“If there are not enough people then knowledge is likely to disappear. There is a critical group size for cultural evolution to be possible”, says Stefano Ghirlanda, one of the scientists behind the study, and Professor of Psychology at Brooklyn College, New York.
One intriguing consequence of the results is that it is not possible to exclude the possibility that cultural capacities are much older; maybe Neanderthals had the same capacities for cultural evolution as modern humans.

“Many finds are very similar for humans and Neanderthals, so with today’s knowledge we cannot answer this question conclusively”, says Kerstin Lidén.

The results are presented in the article ‘Dating human cultural capacity using phylogenetic principles’ in the journal Scientific Reports. The article is available online here:
http://www.nature.com/srep/2013/130507/srep01785/full/srep01785.html

About the Centre for the Study of Cultural Evolution
Research on cultural evolution is a rapidly growing cross-disciplinary research field. In Sweden, research in the field is conducted at the Centre for the Study of Cultural Evolution at Stockholm University. There, biologists, mathematicians, political scientists, historians, anthropologists, archaeologists, linguists, sociologists, psychologists and others are working together in an attempt to understand cultural change. The Centre was established in 2007 by the biologist Magnus Enquist and the historian Arne Jarrick.

For further information
Johan Lind, Associate Professor of Ethology at the Centre for the Study of Cultural Evolution, Stockholm University, tfn +46 (0)8-16 27 47, e-mail johan.lind@zoologi.su.se

Kerstin Lidén, Professor of Archaeology at the Archaeological Research Laboratory, Stockholm University, tfn +46 (0)8-16 29 48, e-mail kerstin.liden@arklab.su.se