Addendum: First, I'm a professional paleontologist, made my living for 30+ years at it. A book may have got me into the field: The Immense Journey, by Loren Eiseley. Eiseley was an anthropologist, interested in human origins, but also a gifted writer. He produced wonderful essays, and some poetry as well. I first encountered his writing in a high school literature text, an essay from the book above mentioned, and it was the only damn thing from the entire book that impressed me. I bought Eiseley's book as a result of that, and soon read several other of his works, including Darwin's Century and The Firmament of Time. His work is simply wonderful. If your son is of high school age, I'd recommend any of those things highly. I also recommend them for any interested adult here. For a younger person, the Eyewitness books would be excellent.
caw