1874-1962 1874-1970 1880-1973 1901-1963 20thcentury agriculture(general) biography biology(general) dewson emmaguffey genetics history jeannette jessica miller molly naturalhistory(general) plantculture plantgeneticists politicalactivists politicalactivity rankin science sources sovietunion sueshelton unitedstates vavilov weis white women womenpoliticalactivists вавилов