From Perspectives on Psychological Science:
Latitudinal Psychology: An Ecological Perspective on Creativity, Aggression, Happiness, and Beyond
Evert Van de Vliert, Paul A. M. Van Lange First Published August 21, 2019
Are there systematic trends around the world in levels of creativity, aggressiveness, life satisfaction, individualism, trust, and suicidality? This article suggests a new field, latitudinal psychology, that delineates differences in such culturally shared features along northern and southern rather than eastern and western locations. In addition to geographical, ecological, and other explanations, we offer three metric foundations of latitudinal variations: replicability (latitudinal gradient repeatability across hemispheres), reversibility (north-south gradient reversal near the equator), and gradient strength (degree of replicability and reversibility). We show that aggressiveness decreases whereas creativity, life satisfaction, and individualism increase as one moves closer to either the North or South Pole. We also discuss the replicability, reversibility, and gradient strength of (a) temperatures and rainfall as remote predictors and (b) pathogen prevalence, national wealth, population density, and income inequality as more proximate predictors of latitudinal gradients in human functioning. Preliminary analyses suggest that cultural and psychological diversity often need to be partially understood in terms of latitudinal variations in integrated exposure to climate-induced demands and wealth-based resources. We conclude with broader implications, emphasizing the importance of north-south replications in samples that are not from Western, educated, industrialized, rich, and democratic (WEIRD) societies.
As Jared Diamond pointed out, it’s been harder down through history for farmers to move to a different latitude because their crops tends to be optimized for a particular length of growing season. But moving east or west is easier because the sun is at the same height in the sky.
Michael Barone pointed out that 19th Century Americans built too many east-west railroads to be consistently profitable, but the north-south Illinois Central was a goldmine. Americans seemed to feel most comfortable moving westward along the same latitude, as depicted DH Fisher’s Albion’s Seed.
There are countries that appear to be excessively wide from east to west to be cohesive, such as 800-mile wide Ukraine.
My impression is that Ryan Coogler’s Black Panther film involves a latitude/altitude theory inspired by the director’s visit to Lesotho, an enclave country within South Africa where 80% of the territory is at least 6,000 feet in elevation. I suspect Coogler hypothesized that Bantus would have eventually evolved a more technological culture in snowy winter places like Lesotho: thus quite a bit of the movie is set above the snowline in Wakanda. But Bantus only got as far south as Lesotho fairly recently — nobody seems to know when exactly, but probably not that many centuries ago.