Uriah

This gets to the heart of the thing: big, muscular Polynesian bodies were not built to do hard labor or to fight, they were built to shiver. Muscle generates heat; without it infants cannot shiver and have to rely on their brown fat deposits instead.

As Houghton says: "Heat production above basal level is related directly to activity of skeletal muscle. At basal level, skeletal muscle contributes only 20% of body heat production, but any increase above basal level comes almost entirely from this tissue."

When Iceland was first discovered agriculture was practiced on a large scale, but after the onset of the Little Ice Age most grain had to be imported and the people subsisted mostly on animal protein, especially fish.

One of the ways Icelanders have apparently adapted to their diet is by acquiring a mandibular torus, a kind of bony outcropping of the lower mouth only seen at the same frequency in the Eskimo, who have a similar hard diet that places great stress on the jaw.

But unlike the Eskimo, since about 1200 fish have been exported on a very large scale from Iceland and the people there have engaged in the activity on a scale unheard of in Europe. As late as 1880, 41% of people in Reykjavík fished for a living and in ultra-cold waters.