This appears to be a newly established "Bergmann's and Allen's Rule" of eyes. Researchers now contend that people in Northern latitudes not only have larger eyes, but they also have larger brains because they need more processing power to see in dim lighting.
"As you move away from the equator, 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.Read the article HERE.
"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, it just means they need bigger brains to be able to see well where they live."
This suggests that someone from Greenland and someone from Kenya will have the same ability to discern detail, but the person from the higher latitude needs more brainpower and bigger eyes to deal with the lower light levels.