The further from the equator people live, the bigger their brain and eyes according to a new Oxford University study. But this does not mean northerners are smarter, merely that they need bigger vision areas in the brain to cope with lower levels of light.
Scientists at the Institute of Cognitive and Evolutionary Anthropology published their findings in the journal Biology Letters after measuring the eye socket and brain volumes of 55 skulls from 12 different countries, dating from the 1800s. They found that the size of both the brain and the eyes could be directly linked to the latitude of the country from which the individual came.
Eiluned Pearce, from the University’s School of Anthropology, said: “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.”
Co-author Professor Robin Dunbar added, “Humans seem to have adapted their visual systems surprisingly rapidly to the cloudy skies, dull weather and long winters we experience at higher latitudes.”
But writing in the Daily Mail, proud Sheffielder and Labour peer Roy Hattersley suggested southerners should now be treated “with pity rather than contempt.”
“The truth is, because they have had it so easy for so long, their brains never extended and grew. Some even say that their brains actually contracted.” Hattersley rejected the study’s claim that this is due to light: “I give them credit for being 50 per cent correct.”
The study takes into account a number of potentially confounding effects, including the effect of phylogeny (the evolutionary links between different lineages of modern humans), the fact that humans living in the higher latitudes are physically bigger overall, and the possibility that eye socket volume was linked to cold weather (and the need to have more fat around the eyeball by way of insulation).
Other studies have already shown that birds with relatively bigger eyes are the first to sing at dawn in low light. The eyeball size across all primates has been found to be associated with when they choose to eat and forage – with species with the largest eyes being those that are active at night.
Oxford University statistics show 50 percent of successful 2010 entrants came from the South West, Greater London or the South East of England. Just 10.7 percent came from north of the Midlands – less than the 15.5 percent of overseas students.