Photo courtesy Three Rivers Press

The ASU professor who discovered ‘Lucy’ updates his theory of evolution.

Considering millions of years of human evolution, what’s 36 years in the grand scheme of things? A lot, it turns out, if you’re a paleoanthropologist.

In Lucy’s Legacy: The Quest for Human Origins ($15, Crown Publishing Group), Arizona State University professor Donald C. Johanson collaborates with science writer Kate Wong to analyze and summarize every major discovery since he found a 3.2-million-year-old set of skeletal remains in an Ethiopian desert in 1974. He named them “Lucy” and forced scientists to reconsider their theories of human evolution.

Lucy’s Legacy is human-readable, with just enough geeky forensic references to stimulate the recently evolved CSI portions of our brains. It describes Johanson’s talks and travels with paleoanthropologists worldwide, who have been logging several startling discoveries. He shares new insights into the Neanderthals, the human-ape connection, and the recent discovery of a 4.4-million-year-old skeleton.

There’s plenty of material for a follow-up. After all, humans are still evolving – and digging.