"This Will Change Everything: Ideas That Will Shape the Future" edited by John Brockman
This book is a collection of about 150 short two page essays answering the question, What in your lifetime will change everything? They polled all sorts of professors, scientists, authors and big thinkers.
Cool backstory on MacLean: He began writing at age 70 after retiring as a professor at the Univ. of Chicago. "River" is an autobiographical account of his youth in Montana.