Tuesday, February 5, 2019

Did cold seasonal climates select for cognitive ability?




Paleolithic artefacts (Wikicommons). The northern tier of Eurasia saw an explosion of creativity that pre-adapted its inhabitants for later developments.



The new journal Psych will be publishing a special follow-up issue on J. Philippe Rushton and Arthur Jensen's 2005 article: "Thirty Years of Research on Race Differences in Cognitive Ability." The following is the abstract of my contribution. The article will appear later.


The first industrial revolution. Did cold seasonal climates select for cognitive ability?

Peter Frost

Abstract: In their joint article, Rushton and Jensen argued that cognitive ability differs between human populations. But why are such differences expectable? Their answer: as modern humans spread out of Africa and into the northern latitudes of Eurasia, they entered colder and more seasonal climates that selected for the ability to plan ahead, since they had to store food, make clothes, and build shelters for the winter. 

This explanation has a long history going back to Arthur Schopenhauer. More recently, it has been supported by findings from Paleolithic humans and contemporary hunter-gatherers. Tools become more diverse and complex as effective temperature decreases, apparently because food has to be obtained during limited periods of time and over large areas. There is also more storage of food and fuel and greater use of untended traps and snares. Finally, shelters have to be sturdier, and clothing more cold-resistant. The resulting cognitive demands fall on both men and women. Indeed, because women have few opportunities to get food through gathering, they specialize in more cognitively demanding tasks like garment making, needlework, weaving, leatherworking, pottery, and use of kilns. The northern tier of Paleolithic Eurasia thus produced the "first industrial revolution"—an explosion of creativity that pre-adapted its inhabitants for later developments, i.e., agriculture, more complex technology and social organization, and an increasingly future-oriented culture. Over time these humans would spread south, replacing earlier populations that could less easily exploit the possibilities of the new cultural environment. 

As this cultural environment developed further, it selected for further increases in cognitive ability. In fact, mean intelligence seems to have risen during historic times at temperate latitudes in Europe and East Asia. There is thus no unified theory for the evolution of human intelligence. A key stage was adaptation to cold seasonal climates during the Paleolithic, but much happened later.



References

Rushton, J.P. and A.R. Jensen. (2005). Thirty years of research on race differences in cognitive ability. Psychology, Public Policy, and Law 11(2): 235-294.


7 comments:

radius said...

Thats quite an intriguing analysis and conclusion. It gives me some confidence that the new threats to mankind (like climate change and the expenditure of natural ressources) can also be mastered by human ingenuity.

john said...

I'm somewhat skeptical. Different environments have different challenges, and superior cognitive ability, all else equal, is going to give an advantage in any of them. Maybe the selection for cognitive ability synergizes with some new aspects of a cold environment, like the cold itself's physiological effects or new dietary staples.

Peter Frost said...

Seasonal environments present a wider array of challenges. In cold seasonal environments, passerine birds have larger brains and more complicated behavioral repertoires.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1559823/


In human societies, time preference is favored by seasonality:

https://pseudoerasmus.files.wordpress.com/2017/01/galor-and-ozak.pdf

akarlin said...

Looking forwards to seeing the full article.

sykes.1 said...

Does this mean Eskimos are geniuses?

Oprah-me said...

Too much cold or dry or hot, too little climate diversity make environment more predictable and decrease necessity to be more creativity. Intense climates make people seek for more stability while creativity is based on less of it.

iffen said...

Does this mean Eskimos are geniuses?


Right, and at what point (and why) did cold weather stop selecting for intelligence? Also, shouldn’t the Neanderthals have built Athens and Rome on the North Sea or Baltic Sea?