Darwin’s changing views on evolution: from centres of origin and teleology to vicariance and incomplete lineage sorting
It is a strange fact that in many ways the first edition of Charles Darwin’s Origin of Species is closer to modern neodarwinism than the sixth and last edition. Sometimes this is attributed to a decline in the quality of the argument, but the opposite interpretation is given here. It is suggested that Darwin’s early work on evolution is naïve and based on the two creationist principles of centre of origin and teleology (panselectionism). This fusion later became the ‘modern synthesis’. However, after the first edition of the Origin, Darwin developed a non-teleological synthesis that integrated natural selection with what he called ‘laws of growth’– phylogenetic/morphogenetic trends or tendencies. Discussion of Darwin’s later, more sophisticated model of evolution has been suppressed in the teleological modern synthesis, but similar ideas are re-emerging in current work on molecular phylogenetics and biogeography. This indicates that the ancestor of a group can be diverse in its morphology and its ecology, that this diversity can be inherited, and that groups usually originate over a broad region and not at a single point.