According to certain anthropologists, the Clovis people are the earliest known inhabitants of North America. They traveled by land-bridge from Siberia more than 10,000 years ago, conquering new lands with tech-savvy arrow points advanced enough to kill off animal species otherwise thought to be victims of climate change. In Adam Johnson's novel Parasites Like Us, the Clovis are held up as monstrously selfish, wasteful forebears to a wave of descendents still unfamiliar with the notion of progress. Whatever they did, though, the Clovis deserve a better champion than Dr. Hank Hannah, the dull protagonist at the center of a novel that leaves a monumental premise in ruins. Writing from the future, Hannah begins by promising to explain how the world fell into another Ice Age. He goes back to a time a lot like the present, during which he was a dispirited anthropology professor in barren South Dakota. One of his students (confoundingly named Eggers) tries to get his doctorate by living solely on Pleistocene-era technology: fire, animal skins, string woven from tendons, an occasional Dorito when he cheats. When Eggers finds a rare Clovis arrowhead in unexplored ground, he wants to try out its storied killing power by felling a pig. Hannah resists, mostly out of fear that his career-making theories might suffer, but the experiment's success leads them to an unsanctioned dig that unearths weird artifacts pointing the world toward apocalypse. Eggers' cartoonish zeal makes for some rousing material, but his beguiling relationship with his mentor exposes Parasites' endemic flatness. Even as the action swells, Hannah stays stuck in broad-stroke purgatory, whining about the present-day world but failing to communicate his fascination with the prehistoric one. "Fishing, anthropology, and indoor gardening seem to exist completely in this space between tedium and futility," Hannah says in a typical show of depressive defeat. But while his tired angst seems like a good foil to the visceral experiences he comes to stare down, nothing changes. Parasites hints at a meditation on humanity's haunted communion with the past, but its intriguing ideas are buried beneath layers of idle ponderousness. The pivotal world-change doesn't arrive until the final third of the novel, and by then, it's hard to pine for characters too unfocused to show that anthropology is less an accumulation of findings than the study of people and the stories they tell.