Please answer the questions. You're the one who's changing the topic by introducing chimera twins and all. All you're doing is avoiding answering the questions.
What criteria do YOU use to base the humanity of a person on then and why?
Why so eager to declare the fetus *not human*? What's the purpose and who gets to decide that anyway?
And another variation: IF the fertilized egg ISN'T human, then when does it become human? What criteria do you use and what if some baby born doesn't fit in with your definition? What do and can you do about it then?
I pointed out a factual mistake in your post. You have not acknowledged that you posted falsely. It's hard to continue a discussion when one's stated facts are incorrect and they will not acknowled that inconsistancy.