Most living things reproduce by laying eggs or scattering seeds or spores (look up "r reproductive strategy"). Mammels have adopted a different reproductive strategy (look up "K reproductive strategy") - where more energy is focused on fewer offspring (it might be argued that males continue the r reproductive strategy whereas placental females follow the K reproductive strategy.) Roughly 2/3 of human embryos do not make it to day 5 (the blastocyst stage). If "life" begins at conception (fertilization), then 2/3 have died in the first week. What the purveyors of the notion that “life begins at conception” are really suggesting is that “the life of an individual human begins at conception”.

Source: New York Times June 29, 2023 00:21 UTC