Homo erectus, Latin for "upright man," arose in Africa 1.8 to 2 million years ago, migrating to Asia and Europe before becoming extinct about half a million years ago. Experts agree it was likely a direct ancestor of modern humans.

Scientists had thought early adult Homo erectus females, because of the assumed small birth canal, would produce offspring with only a limited neonatal brain size. These young would have then experienced rapid brain growth while still developmentally immature, leading researchers to envision a scenario of maternal involvement and child-rearing on par with that of modern humans. But those theories had been based upon extrapolations from the existing male skeleton from Kenya.

1 Isaac Newton the Newtonian Revolution Anglican (rejected Trinitarianism, i.e., Athanasianism; believed in the Arianism of the Primitive Church)
2 Albert Einstein Twentieth-Century Science Jewish
3 Neils Bohr the Atom Jewish Lutheran
4 Charles Darwin Evolution Anglican (nominal); Unitarian
5 Louis Pasteur the Germ Theory of Disease Catholic
6 Sigmund Freud Psychology of the Unconscious Jewish; Atheist; Freudian psychoanalysis (Freudianism)
7 Galileo Galilei the New Science Catholic
8 Antoine Laurent Lavoisier the Revolution in Chemistry Catholic
9 Johannes Kepler Motion of the Planets Lutheran