The notion of Darwinian evolution of forms and entities, according to which all organic species descend from a common ancestor through various processes among which natural selection is the most crucial, forms the framework of current biological investigations. Although biology underwent deep transformations and conceptual shifts since 1859, the initial formulation of this modern idea of evolution is due to Darwin's Origin of species. This promoted a new interpretation of major biological concepts such as adaptation or function, and raised new problems for researchers. The notion of biological evolution entails important consequences regarding the idea of time, especially concerning the time of biological processes and forms, as well as the use of temporal processes in biological explanations. The first section will sketch the historical context of the rise of evolutionism. The second section will explain the major concepts of biological evolution, according to the contemporary version of Darwinism. The third section will then focus on some major controversies that recurrently appeared in the history of evolutionary biology, concerning the process and the pattern of evolution.
