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representation of something small as everything typical? All prominent series of paintings in this genre of prehistoric art— there are no exceptions, hence the example’s power—claim to be portraying the nub or essence of life’s history through time. They all begin with a scene or two of Paleozoic invertebrates. We note our first bias even here, for the prevertebrate seas span nearly half the history of multicellular animal life, yet never commandeer more than 10 percent of the pictures. As soon as fishes begin to prosper in the Devonian period, underwater scenes switch to these first vertebrates—and we never see another invertebrate again for all the rest of the pageant (unless a bit-playing ammonite squeezes into the periphery of a Mesozoic scene). Even the fishes get short shrift (literally), for not a single one ever appears again (except as fleeing prey for an ichthyosaur or a mosasaur) after the emergence of terrestrial vertebrate life toward the end of the Paleozoic era.
    Now, how many people have ever stopped to consider the exceedingly curious and unrepresentative nature of such limited pageantry? Invertebrates didn’t die or stop evolving after fishes appeared; much of their most important history unrolls in contemporaneous partnership with marine vertebrates. (For example, the most fascinating and portentous episodes of life’s history—the five largest mass extinctions—are all best recorded by changes in invertebrate faunas.) Similarly, fishes didn’t die out or stop evolving just because one lineage of peripheral brethren managed to colonize the land. To this day, more than half of all vertebrates are fishes (more than 20,000 living species). Isn’t it absurd to eliminate a vertebrate majority from all further pictorial representation just because one small lineage changed its abode to land?

    FIGURE 1 Three paired views of artistic representations of the history of life to show the unchanging biases that pervade this genre. The three pairs come from the work of Figuier in the 1860s, Knight in the 1940s, and Augusta and Burian in 1956. The first member of each pair shows invertebrates from the early history of multicellular life. The second figure in each pair shows a marine scene from the Mesozoic Era (time of domination of dinosaurs on land). No fish or invertebrates are shown in the Mesozoic scene, but only reptiles that have returned to the marine environment.

    The story of terrestrial vertebrates is just as egregiously biased. First of all, once vertebrates colonize the land, oceans disappear from life’s history, with one "exception" (documented in Figure 1) that actually illustrates the rule: If a "highly evolved" land creature returns to the sea, it may be shown as a representative of diversity within a stage of progress. Thus, Mesozoic marine reptiles may be depicted as contemporaries of ruling dinosaurs on land, but fishes living at the same time are invisible because their stage has been superseded in evolution’s upward march. Tertiary whales are in because mammals then rule the land, but both marine reptiles and fishes of the same period are out as bypassed forms.
    Second, the sequence of land animals only displays our anthropocentric view of shifting mastery through time, not a fair record of changing diversity. Fishes are banished once amphibians and reptiles colonize the land—but why punish fishes for what a few odd relatives did in disparate and unknown environments, especially when oceans, continuously dominated by fishes among vertebrates, cover some 70 percent of the earth’s surface? The origin of mammals extirpates all amphibians and reptiles from view, even though they continue to flourish and to influence mammalian life in ways ranging from Mosaic plagues to the temptation of Eve. The last few paintings always depict humans, even though we are but one species in a small group of mammals (the order Primates contains about two hundred species among four thousand or so