In a geologic instant, the K-T extinction event about 65 million years ago left Earth's skies empty of pterosaurs, extirpated the mosasaurs and their ammonite prey from the seas, and, of course, denuded the land of non-avian dinosaurs. But what if, by some fluke of evolutionary history, this catastrophe never happened and the global summer of the dinosaurs was allowed to continue? What might life on the planet look like today?

Thoughts of modern-day dinosaurs are the stuff of science fiction novels and B-movies—of unexplored islands and jungle plateaus teeming with vestiges of prehistoric life—but the Scottish geologist Dougal Dixon presented his own remarkably prescient and colorful answers to these questions in The New Dinosaurs: An Alternative Evolution. The speculative creatures within its pages—given whimsical names such as "Lank," "Zwim," "Lumber," and "Tubb"—were imaginative adaptations of Cretaceous life-forms modified to survive in a modern-world devoid of humans. After all, had dinosaur diversity not been rapidly winnowed down by extinction, mammals might have never gotten a shot to achieve ecological dominance. Our own evolution could have been cancelled.

Though undeniably speculative when it was published in 1998, The New Dinosaurs was greatly influenced by the state of dinosaur science at the time. By the late 1980s the cultural shift in paleontology celebrated as the "Dinosaur Renaissance" was in full swing—images of slow, stupid, swamp-bound and drab dinosaurs were rapidly being replaced by visions of active, agile and vividly colored animals that were far more bird-like than previously imagined. There was even a growing body of evidence that birds were the direct descendants of dinosaurs, and Dixon extrapolated from these paleontological trends to create a collection of colorful, behaviorally complex dinosaurs unlike any seen before.

Amazingly, in some respects, Dixon's fanciful menagerie was spot on. In the two decades since the book was published, researchers have found fossil evidence of dinosaur biology and behavior that are startlingly close to what Dixon imagined. Dinosaurs did not need an extra 65 million years to acquire some of the bizarre body shapes, adaptations and behaviors that Dixon imagined. As fossil discoveries have come under the scrutiny of the latest generation of paleontologists, dinosaurs have become ever-stranger.

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