I was discussing human life and that was the topic of this tread.
Well then, science tells us that
human life has been around for about 200 thousand to 500 thousand years ago, depending on what you define as "human".
You're still asking the wrong question.
I respectfull disagree that the question of when an individual life begins is not revelant to the abortion debate.
I think all agree that the intent of abortion is to eliminate a human life. See Planned Parenthood.
Clearly not everyone agrees with you there.
Personally, I agree that a zygote is a "human life". I would not agree that it is an
individual human life, nor a person. Of course, this is just a personal opinion and others may well disagree. Whatever the case, it's not a question that can be directly answered by science, only informed by science. Ultimately, a subjective ethical judgement must be made.
How would you define "personhood"?
However I define it, a functioning brain would seem to be a requirement, along with the ability to survive independently of the mother to some extent. But like I say, it's a personal opinion, not one that can be objectively defined.
Is threre no human life until personhood?
That's, in my opinion, a pretty dangerous moral slope to stand on.
Well welcome to the world! In the real world we have to make these kinds of judgements. We live in a society of laws and laws are clumsy things. In the absence of a clearly defined natural boundary of person-hood, we have to make a judgement and create a (somewhat arbitrary) legal cut-off point. It's not a perfect solution but then, we don't live in a perfect world.
Mutate and Survive