water people??

How do people come up with ideas for what human would look like if they evolved to live in the water, I doubt we would resemble humans at all and would just look like weird fish. I mean we came from water origionaly right so what's the point of evolving to land, then back to water! This makes me wonder what it would be like in a paralel universe were butterflys never had wings, they might not survive past being a baby caterpillar and I wonder if kids would still love them. At that point they as well be big ants *cry*. Cash fact of the week: Cash is scared of butterflys!!!