"The "Genesis kind" is generally equivalent to what is now called "species. The variation is due to flaws in our humanly devised classification system.
There are more different types of dogs than any other species in the world—yet scientists recognize them all to be in the same "species." There often can be wide variations within a species, because the DNA permits it. In some species, a narrow number of possible subspecies are possible. The cheetah has such narrowed DNA that it can only produce cheetahs—and no varieties of subspecies.
Plant and animal breeding can produce new subspecies, but they are never quite as hardy as the basic species."
If two entities can interbreed, are they the same species?
If two entities cannot interbreed, are they different species?