Category: Nutrition

Some 160,000 years ago, with the Earth in the middle of an Ice Age, a group of modern-looking humans lived in a cave a few kilometers from the sea near the southern tip of Africa. There they huddled around hearths, chipped stone bladelets, and perhaps decorated their bodies or objects with a red pigment. The site, Pinnacle Point near Mosselbaai in South Africa, has just been unveiled to the public, and it is touted as the earliest evidence of human coastal settlement, and of our use of the sea’s resources as food. Yes, because our human troop in the cave also feasted on shellfish and other seafood. Anthropologists think that many similar sites existed, but that their remains have been washed away as sea level rose with the melting of the glaciers. The Pinnacle Point cave is now a sea cliff, 15 metres above the waves of the Indian Ocean.

The excavators of the site think that during the Ice Age savannah productivity was low, and human populations set out in search of better places to live, eventually finding them in coastal areas — which are now submerged, which is why no similar sites of this antiquity have ever been found. Shellfish would then have become a critical source of food, and the study contends that humans then followed these resources out of Africa, moving along the Indian Ocean coast to the Red Sea, the Middle East, and beyond…

As far as the cold waters of the North Sea, in fact. Fast forward to just a few thousand years ago: the late Mesolithic in northern Europe. In places like Britain and Denmark, humans still have a basically marine diet. Then agriculture comes, either in the form of knowledge or of farmers, and suddenly — the evidence is that the change was very rapid — the eating habits of 150,000 years are gone. That’s gotta hurt. In particular, what did people do about vitamin D, which is plentiful in seafood but in cereals, well, not so much. Vitamin D is made in the skin when it is exposed to sunlight. As Razib points out at Gene Expression, we know that genes for skin pigmentation have been strongly selected. Is it the sudden transition to low vitamin D foods in the Neolithic that accounts for the paleness of northern European skins?