Heredity before genetics: a history.

Two hundred years ago, biologists did not recognize that there was such a thing as 'heredity'. By the 1830s, however, insights from medicine and agriculture had indicated that something is passed from generation to generation, creating the context for the brilliant advances of Mendel and Darwin. Recent work on the history and philosophy of science has shed light on how seventeenth-, eighteenth- and nineteenth-century thinkers sought to understand similarities between parents and offspring.