Some were accompanied by TV documentaries.
All were by Dougal Dixon, and were titled "The New Dinosaurs," "After Man," and "The Future is Wild."
"The New Dinosaurs" speculated on what might have evolved if the 65 million-years-ago extinction had never happened. "After Man" is pretty self-explanatory. If humanity becomes extinct, what will the rest of life evolve into? "The Future is Wild" assumes humanity leaves the earth for space, and follows evolution and the Earth's climate through the next 200 million years.
There's another one I haven't read called "Man After Man," which postulates the future of the human species under genetic pressure. Seems a bit creepy.
All of these, for some reason, seem to be mostly out of print. Used bookstores and libraries, then.
Off Topic » in reply to My first thought: "Giant naked mole rat?"
There were a few books like that.