The Stone Age is, in fact, divided into various stages. Dominating the period is the Palaeolithic Age, which most anthropologists would extend down to roughly 11,000 B.C. Within the Stone Age in general, however, scholars also speak of an Upper Palaeolithic Era, beginning around 40,000 B.C. They draw attention to some significant changes in human behaviour around this date, including the appearance of sophisticated cave paintings, and evidence of religious ideas. Humans also began producing the most effective, finely crafted tools such as fishhooks, arrowheads, and sewing needles made from organic materials, such as wood or animal bone. Yet, despite these important developments, the basic patterns of human life changed little during this era. Virtually all human societies before 11,000 B.C. consisted of small bands of hunter-gatherers that moved incessantly in search of food. Because they could not stay in any one location for long, these groups left no continuous archaeological record whereby we might trace the development of their culture. Our knowledge of them is, therefore, very limited.