Demuth’s decision to portray the region’s energy exchanges is an inspired choice. In the frozen earth and teeming waters of the Bering Strait, there are many losses to tally. Grasping their relationship to one another is crucial. “Floating Coast” is organized into five parts: Sea, Shore, Land, Underground and Ocean. Each section overlaps in time with the one before, so Sea is about the years 1848–1900, while Shore is about 1870–1960 and so on. The book’s nonlinear structure reinforces the message of interconnection. It’s not possible to appreciate the history of the sea without considering the shore around it. Creatures and resources move back and forth perpetually.

And so “Floating Coast” journeys across time, geography, cultures and beings to show where energy goes. Ever-larger acts of consumption transform individuals into structures and ideas. The calories available in plankton, mollusks and people are applied to build gulags, mines and mission schools, which in their turn become beliefs about morality, labor and time. What Demuth calls the “chain of conversions” forms a loop. Alaskan caribou herds, for example, fueled a demand for reindeer meat, antlers and pelts in the 1960s, then undid the market’s expectation of growing returns when they began dying in droves in the 1970s. If the bodies of caribou led to an idea — that animals could be converted into wealth — the idea failed when their bodies did. Human systems are only one part in the flow of energy.

“On the ideal tundra,” Demuth writes, “people made history by separating themselves from nature, and then rendered natural variation static. Only people were supposed to change, and do so for the better.” The actual tundra proves this is not the case. Change is constant, far from only human, and often beyond our understanding or control. Caribou breed and die on their own schedules. Whales have private strategies for evading boats. Oceans warm despite any government’s denial that they should do so. The Bering Strait is an object lesson, reminding us that people are part of, not superior to, the natural world. We cannot disconnect ourselves. The energy we siphon, lives we take and lands we alter shape us in turn.

The book’s refutation of human exceptionalism is evident in its narrative approach. Demuth, who moved to the Yukon from Iowa at age 18 to apprentice under a Gwitchin sled-dog musher, writes with care and caution as a foreigner to the region. Her first source in writing “Floating Coast” is indigenous Beringian histories, both as recorded in ethnographic materials and as transmitted in Yupik, Inupiat and Chukchi oral traditions. Where people’s voices do appear in the book, they are frequently in the form of direct quotes from Beringians. But no single person is given particular authority. One quote follows the next. The overall effect is of a chorus.