That doesn't matter at all. Animals have differences.
A wolf and a dog are the same animal, but one is domesticated. THAT'S A DIFFERENCE. A bird and a fish are the exact opposite! Well, except for that they breathe, have a heart that beats, they eat food, and they're alive, but every creature on earth (EVEN TREES!) do all of these things.
Well, plants might not have hearts, but other then that, everything on earth except rocks and sand, dirt, other minerals found underground, anything not gene-spliced while also being man-made and water itself does this.