As I said, the authority for it is God, and scientists don't regard that as any kind of authority. So I don't EXPECT scientists to bother. I was merely stating a fact in explanation of why all the scientific accoutrements to the idea that everybody is demanding are not forthcoming.
Except for some writings that various different people interpret in various different ways, and often disagree if it is from god or not, God has been very silent on the issue of what a 'kind' is.
Now, if God was our creator, and God gave us a brain, then, by golly by gosh, we should USE that brain.
So, based on your observations of the real world, and comparing it to the scriptures, what definition of a Kind that you can use so that we can actually make sense out of the use of the word 'kind', instead of it being this ill defined word that just means about anything.