where does the term grandfathered in come from
Grandfather clause The term originated in late nineteenth-century legislation and constitutional amendments passed by a number of U.S. Southern states, which created new requirements for literacy tests, payment of poll taxes, and/or residency and property restrictions to register to vote. States in some cases exempted those whose ancestors (grandfathers) had the right to vote before the Civil War, or as of a particular date, from such requirements. The intent and effect of such rules was to prevent poor and illiterate African-American former slaves and their descendants from voting, but without denying poor and illiterate whites the right to vote. Although these original grandfather clauses were eventually ruled unconstitutional, the terms grandfather clause and grandfather have been adapted to other uses.
Anatomically modern human Homo sapiens evolved from "archaic" or "robust" predecessors (Homo heidelbergensis, or a related offshoot from Homo erectus) around 315,000 years ago. The divergence of modern human populations dates to shortly after this time, the oldest division being that of the hunter-gatherer populations of Southern Africa, although there have been numerous events of admixture both among modern populations and between modern and archaic ones.