Many misunderstand how heredity works Many misunderstand how heredity works Until Mendel did his experiments in the mid 1860s, no one had a sound idea of how heredity worked.
Most people vaguely know there are three to one ratios for many genetic disorders.
Most of humanity, however, still favors some very wrong ideas about heredity. There is no such tie. Most retarded children have two normal parents. Many more people believe that heredity can be altered or trained by exposure to the right environment. There are lots of claims for birthmarks from mothers allegedly seeing frightening things during pregnancy.