Figure 1.

Timeline of geological epochs, archeological periods in human prehistory and history, and the effects of sunshine and dietary calcium. The migration of man out of Africa to northern and southern latitudes 60–130 k.y.a was associated with depigmentation. Transition from the geological Pleistocene epoch to the Holocene epoch coincided with the “agrarian revolution” 10–12,000 years ago and from the archeological Paleolithic period (hunter gatherer tool makers) to the Neolithic farmers. The agrarian revolution happened at different times in different parts of the world, and wherever it happened, it was associated with an increase in dietary calcium and crowding of people in cities. The industrial revolution, which began in Europe in the second half of the 18 century, was associated with rickets – “the English disease” due to industrial air pollution. The transition to the nuclear age, also called the digital age, define also the transition to the Anthropocene epoch, which is associated with further diminution of UVR exposure in humans.