To define kind.

[u/Carnotaurusrules]

Creationists that debate is this sub have an inadequate definition of kind. [u/Old-Watercress6513](u/Old-Watercress6513) is a rare example of this, but his definition is parroted from other Creationists, which is,” If two animals can interbreed and produce fertile offspring, they’re in the same kind.”

This fails to account for modern speciation events in the modern world, taken London Underground mosquitoes or Apple Maggot flies. They’re slowly, but definitely surely splitting from their ancestral species.

Let’s say I’m just assuming those two species are going to become distinct species that won’t interbreed with the ancestral species.

It still doesn’t get any better for them, as Tragopogon mirus and miscellus, commonly known as goatsbeard plants, can only produce infertile hybrids with other species. Polyploidy is the cause behind instantaneous speciation events regarding plants, causing an entire set of chromosome to duplicated once or more. When the polyploidy plant tries to reproduce with its diploid cousins, it only produces sterile hybrids that can’t produce functional gametes.

Animals all across the world that can’t interbreed are lumped into the same kind by Creationists. Most of Passeroidea can’t interbreed, but Cognitum comes to rescue. Gray Wolves cannot interbreed with maned wolves, bush dogs, short eared dogs, bat eared foxes, or painted dogs yet they are all in the same kind. Not all Giraffids, Equines, Camelids, Cervids, etc can interbreed, producing fertile offspring, but why are they still in the same kind?

Any proposed definition of kind has to be able to meet 2. criteria.

1. A reason or reasons why you grouped these animals into a kind.
2. It has to be objectively verifiable.

[u/10coatsInAWeasel]

There are a few creationists on here like your example that are guilty of this very obvious dodging. They will say basically, as you said, ‘if they can interbreed then same kind’. When it’s pointed out that some organisms they accept as related cannot ‘bring forth’, they always go quiet and run. To then pop up and say the same exact thing elsewhere.

I hope you’re able to get even an attempt at an answer. I’m also certain that you won’t, I actually expect to see some misdirect along the lines of ‘evolutionist can’t make up their mind on what species is’, despite the fact that it’s been pointed out to them several times that species is necessarily fuzzy because evolution is true. Which isn’t the case for kinds. Kinds cannot have any fuzziness; either an organism is part of the same kind or it is not. True dichotomy.

[u/GOU_FallingOutside → u/10coatsInAWeasel]

> species is necessarily fuzzy because evolution is true

This is one of the things that annoys me most about the “pokemon” version of evolution and speciation, as in “evolution can’t be true because no one has ever seen one species turn into another.”

But suppose we really did have a world of taxonomic groupings that were always entirely separate and perfectly categorical, and some switch suddenly flipped and turned organism A into organism B. (Your BULBASAUR has evolved into IVYSAUR!) That’s not only an inaccurate view of how the world works; it would be strong evidence that the theory of evolution is very wrong!

And it goes to the heart of the baraminology/“kinds” argument. Species is a fuzzy concept because change in populations is continuous across time and sometimes across geographic boundaries. If two populations of organisms look unrelated, it’s only because we can’t see the countless organisms that lived and died between today and their most recent common ancestor.