The "kind" concept - and its companion hyper-evolution - were made up by YECs when it became obvious that all animal species would not fit on the ark. It is no more Biblical than it is scientific.
Maybe but there is another explanation:
At one time, I think, a "kind" was exactly a species. You see this in many newbie, hit-and-run posters here. It is obvious this is what the Bible thinks a "kind" is.
However, aside from the ark problem, speciation and new genera have been demonstrated to occur. Thus the YEC'ers were forced to move the line up.
It seems they learned a lesson and WILL NOT define kind. They've had to move the line and now it is "high" enough that humans and their relatives are one kind if they have a single consistent and clear definition.
The "big guns" know this and are not about to be caught with anything clear enough to be actually discussed along those lines.
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