Why? Dolphins are probably much smarter than apes.
newsflash dumbass, we are apes. How in the **** would you get a single species (we can all interbreed and have viable offspring) from your idiocy in the OP? Not only do you not understand evolution (which is not as "missing linky" as you want it to be), you dont understand basic reproductive biology or basic english (posit clearly means to suggest or postulate).
I actually agree with OP. I've seen someone blow a dolphin, so what's to say, a woman can't have sex with a dolphin and make mini half dolphin babies. I think that's what the movie, little mermaid was about