Before Roe v. Wade legalized abortion, all science texts taught the biological truism that the life of any individual of any species begins at conception, when sperm and ovum unite to create a new being with its own complete and unique genetic code, distinct from both father and mother. All growth and development from then on are a matter of degree, a gradual unfolding of what is already there. There is no specific or distinct point in our development when we become human. (What were we before that? Birds?) Only when abortion became legal did the science textbooks change their language and cease teaching this truism-not became of any new science but because of a new politics.Catholic Christianity (234-235)