Australopithecines, dinosaurs, trilobites—such fossils conjure up images 
    of lost worlds filled with vanished organisms. 
    But in the full history of life, ancient animals, even the trilobites, 
    form only the half-billion-year tip of a nearly four-billion-year iceberg. 
    Andrew Knoll explores the deep history of life from its origins 
    on a young planet to the incredible Cambrian explosion, 
    presenting a compelling new explanation for the emergence of biological novelty.