DNA

Although the science of genetics has its origins in the work of Gregor Mendel in the mid-1800s, various theories of inheritance preceded Mendel. These theories generally assumed that there existed an inheritance of acquired characteristics: the belief that individuals inherit traits that have been strengthened in their parents. Today, the theory is commonly associated with Jean-Baptiste Lamarck, who used this pattern of inheritance to explain the evolution of various traits within species (these changes are now understood to be the product of natural selection rather than a product of soft inheritance).