<P> The study of prehistoric medicine relies heavily on artifacts and human remains, and on anthropology . Previously uncontacted peoples and certain indigenous peoples who live in a traditional way have been the subject of anthropological studies in order to gain insight into both contemporary and ancient practices . </P> <P> Different diseases and ailments were more common in prehistory than today; there is evidence that many people suffered from osteoarthritis, probably caused by the lifting of heavy objects which would have been a daily and necessary task in their societies . For example, the transport of latte stones, though this practice only started during the neolithic era which involved hyper extension and torque of the lower back, while dragging the stones, may have contributed to the development of micro fractures in the spine and subsequent spondylolysis . Things such as cuts, bruises, and breakages of bone, without antiseptics, proper facilities, or knowledge of germs, would become very serious if infected, as they did not have sufficient ways to treat infection . There is also evidence of rickets, bone deformity and bone wastage (Osteomalacia), which is caused by a lack of Vitamin D . </P> <P> The life expectancy in prehistoric times was low, 25--40 years, with men living longer than women; archaeological evidence of women and babies found together suggests that many women would have died in childbirth, perhaps accounting for the lower life expectancy in women than men . Another possible explanation for the shorter life spans of prehistoric humans may be malnutrition; also, men as hunters may have sometimes received better food than the woman, who would consequently have been less resistant to disease . </P> <P> Plant materials (herbs and substances derived from natural sources) were among the treatments for diseases in prehistoric cultures . Since plant materials quickly rot under most conditions, historians are unlikely to fully understand which species were used in prehistoric medicine . A speculative view can be obtained by researching the climate of the respective society and then checking which species continue to grow in similar conditions today and through anthropological studies of existing indigenous peoples . Unlike the ancient civilisations which could source plant materials internationally, prehistoric societies would have been restricted to localised areas, though nomadic tribes may have had a greater variety of plant materials at their disposal than more stationary societies . </P>

What did early human beings believe caused illness and disease