A Ph.D. in genetics named Ricki Lewis uses a “DNA science” blog to ask a cogent question: “When Does A Human Life Begin?” She then presents 17 potential time points, from sperm and egg through the joke, “acceptance into medical school.” Two warrant quoting. From the piece:
3. Of the hundreds of sperm surviving the swim upstream to the oocyte, one jettisons its tail and nuzzles inside the much larger cell, which obligingly becomes an ovum, completing its own meisosis. A fertilized ovum = conception.
14. A fetus has a chance of becoming a premature baby if delivered.
She chooses 14: But notice the switcheroo she pulls to get the answer she wants:
My answer? #14. The ability to survive outside the body of another sets a practical limit on defining when a sustainable human life begins.
But the question was, “When does a human life begins,” not, “When does a sustainable human life begin?”
The scientifically correct answer is number 3, at the latest. Embryology text books tell us that a new human life begins at the completion of the process of fertilization. That is when a distinct human organism–a new human being–is formed.
This is her rationale for choosing 14:
Having a functional genome, tissue layers, a notochord, a beating heart … none of these matter if the organism cannot survive where humans survive…
But as long as the nascent human being remains in the womb (or Petri dish) where it can survive, it is a human being. If it is removed from a survivable environment, the human being that existed will die–which is true of all humans. But that does not mean he or she is a Martian, a mere collection of cells, or some other non human descriptive.
And check this unscientific opinion:
Until an artificial uterus becomes a reality, technology defines, for me, when a human life begins, rather than biology.
That’s ideology, or philosophy–not science.
Think of it this way: A human being can’t survive unassisted on the moon absent the creation of an artificial atmosphere via technology. Because the technology could break, and the astronaut die, does that make the moon astronaut less human?
Of course not. The same goes for the embryo and fetus who are living in the womb.