The process of evolution of different species in a given geographical area starting from a point and literally radiating to other areas of geography (habitats) is called adaptive radiation. Darwin finches is an example of adaptive radiation. Analogous structures are anatomically different structures though they perform similar functions and these are a result of convergent evolution. Example: wings of butterfly and bird. Homologous organs are anatomically similar structures but perform different functions according to their needs and these are a result of divergent evolution. Example: bones of forelimbs in man and whale. Anthropogenic evolution refers to the evolution that is caused by human beings. Example: selection of resistant varieties due to excessive use of herbicides and pesticides.