Full House Read Free

and nature is knowable, but we can only view her through a glass darkly—and many clouds upon our vision are of our own making: social and cultural biases, psychological preferences, and mental limitations (in universal modes of thought, not just individualized stupidity).
    The human contribution to this equation of difficulty becomes ever greater as the subject under investigation comes closer to the heart of our practical and philosophical concerns. We may be able to apply maximal objectivity to taxonomic decisions about species of pogonophorans in the Atlantic Ocean, but we stumble in considering the taxonomy of fossil human species or, even worse, the racial classification of Homo sapiens.
    Thus, when we tackle the greatest of all evolutionary questions about human existence—how, when, and why did we emerge on the tree of life; and were we meant to arise, or are we only lucky to be here—our prejudices often overwhelm our limited information. Some of these biased descriptions are so venerable, so reflexive, so much a part of our second nature, that we never stop to recognize their status as social decisions with radical alternatives—and we view them instead as given and obvious truths.
    My favorite example of unrecognized bias in depicting the history of life resides quite literally in the pictures we paint. The first adequate reconstructions of fossil vertebrates date only from Cuvier’s time, in the early nineteenth century. Thus the iconographic tradition of drawing successive scenes to illustrate the pageant of life through time is not even two centuries old. We all know these series of paintings—from a first scene of trilobites in the Cambrian sea, through lots of dinosaurs in the middle, to a last picture of Cro-Magnon ancestors busy decorating a cave in France. We have viewed these sequences on the walls of natural history museums, and in coffee-table books about the history of life. Now what could be wrong, or even strongly biased, about such a series? Trilobites did dominate the first faunas of multicellular organisms; humans did arise only yesterday; and dinosaurs did flourish in between.
    Consider three pairs of scenes spanning a century of this genre, and including the three most famous practitioners of all time. Each shows a Paleozoic and a Mesozoic marine scene. In each, the Paleozoic tableau features invertebrates, while the Mesozoic scene shows only marine reptiles that have descended from terrestrial forms. The first pair comes from a work that established the genre in the early 1860s—Louis Figuier’s La terre avant le déluge (The World Before the Deluge; see Rudwick’s fascinating book, Scenes from Deep Time, for a survey of this genre’s foundation in the nineteenth century). The second is the canonical American version, painted by Charles R. Knight, greatest artist of prehistoric life, for an article in National Geographic Magazine (February 1942), and titled Parade of Life Through the Ages. The last pair represents the equally canonical European work of the Czech artist Z. Burian in his 1956 work written with paleontologist J. Augusta and entitled Prehistoric Animals.
    So why am I complaining? No vertebrates yet lived in the early Paleozoic, and marine reptiles did return to the sea during dinosaur days in the Mesozoic. The paintings are "right" in this narrow sense. But nothing can be more misleading than formally correct but limited information drastically yanked out of context. (Remember the old story about the captain who disliked his first mate and recorded in the ship’s log, after a unique episode, "First mate was drunk today." The mate begged the captain to remove the passage, stating correctly that this had never happened before and that his employment would be jeopardized. The captain refused. The mate kept the next day’s log, and he recorded, "Captain was sober today.")
    As for this nautical tale, so for the history of life. What can be more misleading than the