I must go back and double-check how the 120s are classified in the Dewey Decimal system, because this is a seriously strange mixture: part biologists on their big unifying theories of life, part philosophers on everything, and part musings on the afterlife.
My three possibilities:
121.6 Six Impossible Things Before Breakfast: The Evolutionary Origins of Belief, by Lewis Wolpert (2006).
128 The Philosopher and the Wolf: Lessons from the Wild on Love, Death, and Happiness, by Mark Rowlands (2008).
129 Spook: Science Tackles the Afterlife, by Mary Roach (2005).