The higher the latitude, the bigger the brain

New research shows that people living in high latitudes have eyeballs and bigger brains than others.

The results published in the latest issue of the Royal Society Biology Letters show that an increase in brain and eye size allows people to observe better in equatorial places.

Discovery news page quoted Mr. Robin Dunbar, Director of the Institute of Evolutionary and Cognitive Anthropology at Oxford University (UK): 'People live on the Arctic Circle (latitude 66 ° 33 ′ 44 ″ north of the equator) have eyeballs are 20% larger than people living on the equator. Those who live in high latitudes observe more closely than those who live right at the equator. The whole problem is that they need better vision to compensate for lower light levels at high latitudes. '

Children in the Arctic - (Photo: Discovery)

In the study, Mr. Dunbar and his colleague Eiluned Pearce measured the skulls of 55 individuals from 12 different latitudes, from Scandinavia to Kenya and then Australia, focusing on volume-related figures. eye sockets and skulls. These people lived about 200 years ago. Their skulls are now part of collections collected at Oxford University's Museum of Natural History and Cambridge University Duckworth Collection.

The researchers found positive relationships between absolute latitude, eye socket volume and brain size. Eyeballs vary in size from 1/4 to 1/3 of 1 ounce (1 ounce = 28.4 cm3). Brain size varies from about 40.6 ounces in Micronesia (smallest) to 50.2 ounces in Scandinavian (largest). Residents of the Arctic Circle are not considered, but researchers estimate '20% greater ' based on their existing data.

Scientists quickly determined that brain size is not necessarily correlated with intelligence.'What we want to determine is that the larger brain of people living in high latitudes doesn't mean they're smarter. That just means that they increase the size of the brain area for vision, thus increasing brain size in general , 'Pearce explained.

Larger eyeballs allow to receive and process images in more detail. The amount of light that hits the earth's surface as well as the length of the day decreases as the latitude increases, so people living in these areas need more refined eyes. This effect has been demonstrated in previous studies in birds and primates, but this is the first study to show that humans are not an exception.