Humans who live at higher latitudes have larger eyes and more processing power in their brains to deal with visual information compared with those living nearer the Earth equator, a study suggests.
"As you move away from the equator to north, there's less and less light available, so humans have had to evolve bigger and bigger eyes," said Eiluned Pearce from the Institute of Cognitive and Evolutionary Anthropology at Oxford University, a lead author on the study.
"Their brains also need to be bigger to deal with the extra visual input. Having bigger brains doesn't mean that higher-latitude humans are smarter than others , it just means they need bigger brains to be able to see well where they live , the area with less light."
This suggests that a person from Greenland and the other from Kenya will have the same ability to discern details, but the one from the higher latitude areas needs more brainpower and bigger eyes to deal with the lower light levels.