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Perhaps "I, Weapon"? That one involves a far future where there's a combination of adaptation to given environments aided by genetic engineering (including all of the common tropes from heavyworlders to aquatic to flying as well as the people living inside the moon who've engineered away things like hair and belly buttons that they feel get in the way) to shepherded evolution (at some point, humanity was enslaved by an alien race who found us delicious. They bred for lower intelligence, large size, docility, and long earlobes [they found it aesthetically pleasing]. One of the dirty secrets of humanity is that humans found the meat delicious too and continue to farm these descendants).
The main thrust of the book is that there's a form of invading aliens, tripedal creatures, and a secret cabal of humanity is breeding together specific exemplars of the branches of the human race in hopes of creating a potential savior. Very entertaining book if a little iffy on some of their science.
There's also Future Evolution by Peter Ward, but that and After Man are illustrated coffee table books, and it sounds like you're describing something in more of a traditional novel format. If you do mean some kind of picture book, I think Life Off Earth by Ian Ridpath had a chapter about adapting humans to other worlds (but I haven't been able to find a copy since the one in my grade school's library, so I could be way off base here).
Now, this is really going out on a limb, but could it be Godwhale by T J Bass?
This happens in the Ringworld novels. Humans evolved based on their environments, so you have Vampires, Grass Giants, Ghouls, etc. If so, the Wikipedia page you're looking for is here: http://en.wikipedia.org/wiki/Hominids_of_the_Ringworld
Pioneers, by Phillip Mann, is about a future where a small number of humans are genetically engineered to be good first settlers on planets that are being considered for colonisation. There's a bird dude, and a plant dude, and the cover was a guy with a bear arm. I'm not sure if this is close to what you're looking for or not.

This one is a sci-fi novel I found out about on the wiki of all places. It takes place in a future with...space travel, I think. The main thing I do remember is that all the wildlife is evolved from homo sapiens. They're all adapted for certain environments. They have names like "hunters", "swimmers" "lurkers", etc. Those aren't exact names, I just know they sounded like that.