Evolutionary Aspects of Bone Health

Abstract

The period during which our human ancestors evolved is miniscule in relation to the evolutionary record of all living things. However, the speed with which the human species changed is unique among animals. This article reviews basic evolutionary forces as well as the timeline from the first appearance of early hominids through the modern age. The distinctive feature of human evolution is the combination of biology and culture that characterizes human adaptation. Presumably, the need for specific skeletal characteristics (e.g., size, shape, density) changed as early hominids experienced major shifts in adaptation. These shifts include expansion from the tropics to a wide range of environments; transition from hunting and gathering to food production; change from physically active lifestyles to relative sedentism; and increase in life expectancy. These changes can be related in some ways to the modern problem of osteoporosis. An understanding of man's evolutionary past holds important lessons and provides insight into safeguarding this aspect of health as man moves into the new millennium.