Ten milestones that have helped to tell life's story:
-Walter Alvarez's asteroid theory of dinosaur extinction
-The first identification of dinosaur fossils
Stanley Miller's simulation of the early atmosphere, leading to organic compound formation
-Robert Ballard's discovery of hydrothermal vent ecosystems
-Charles Walcott's analysis of the Burgess Shale
-The Linnaean classification system
-Darwin's theory of natural selection
-Donald Johanson's "Lucy"
-Mary Leakey's Laetoli footprints
-And Michel Brunet's Toumai skull
