Anything using DNA is incapable of staying the same. DNA cannot replicate without error.
Is a coyote not a coyote if it has 5% wolf ancestry? It can BE just fine without fitting nicely into one neat category.
Humans want things to be clearly defined. Nature is usually not so obliging.
And yet in this matter, it appears you want Nature to "oblige" you, by conforming to your ideological commitments.