Original sentence: In many instances life expectancy varied considerably according to class an gender.Many foraging cultures believed that life began at age 2
Edited sentence: Also of note, these numbers contain a significant ethno-bias by including infanticide but not including abortion.In many instances life expectancy varied considerably according to class, and knowledge of the environment.Many foraging cultures believed that life began at age 2, putting infanticide in the same category as abortion in the view of some moderns