The disappearance of the last ice-sheet, which marked the end of the Pleistocene period and, with it, the end of the Palaeolithic, led to the rise of a new culture, generally referred to as the Mesolithic, in which the Palaeolithic economy of food gathering, though basically unchanged, was partly modified in some parts of the world under the influence of new climatic conditions.
The big animals of the Pleistocene, on which the Palaeolithic hunters had largely depended for their food, disappeared everywhere except in parts of Africa, and their place was taken by the present-day fauna. Also with the ice retreat new regions were opened to settlement. The stone implements of the Mesolithic cultures were still produced by chipping, but a preference was shown for extremely small forms (microliths), often of geometric shapes. Some of these forms had a wide distribution in Asia, Africa, and Europe, showing that there were certain cultural relations and also actual movements of peoples-the latter probably connected to some extent with the drying up of the Sahara and Central Asiatic regions.
The Mesolithic period is usually considered to have begun (in northern Europe at least) circa 8000 B.C., and Mesolithic cultures lasted for several thousand years until supplanted (at different dates in different areas) by the food-producing economy of the Neolithic peoples.