Once fertilized, he fertilized egg (now called a zygote) is a human being.
Nothing ever authorized the legal separation of human beings into two classes: one with rights, and one without.
It's the premise of Nazism and slavery.
And you're right: chimpanzees and broccolis don't come from human mating. Every species produces offspring according to its species.
broccoli. I used calzones.
That’s why you’ll live 30 years longer than me!