His work later took him to Haiti to investigate folk preparations implicated in the creation of zombies, an assignment that led to his writing Passage of Darkness (1988) and The Serpent and the Rainbow (1986), a bestseller.

[4] Davis has written for National Geographic, Newsweek, Premiere, Outside, Omni, Harpers, Fortune, Men's Journal, Condé Nast Traveler, Natural History, Scientific American, National Geographic Traveler, The New York Times, Wall Street Journal, Washington Post, The Globe and Mail, Rolling Stone, and numerous other international publications.

His account weaves together the three Everest expeditions in 1922, 1923 and 1924, set in the shadow of the Great War, by finding "a unifying thread in the person of George Mallory, the scatter-brained Adonis and Bloomsbury favourite whose fate would enthral the nation," wrote John Keay in Literary Review.

[citation needed] Davis is the co-curator of The Lost Amazon: The Photographic Journey of Richard Evans Schultes, first exhibited at the National Museum of Natural History, Smithsonian Institution, and currently touring Latin America.

A first collection of Davis's photographs, Light at the Edge of the World, appeared in 2001 published by National Geographic Books, Bloomsbury, and Douglas & McIntyre.

In 2022 Davis curated an exhibition at the Bowers Museum in Santa Ana, California that highlighted the history of expeditions to the peak of Mount Everest.

He is a member of the International Advisory Board, Hunt Consolidated, PLNG, and has also been engaged in Journey to Zero, a three-year campaign sponsored by Nissan and TBWA to support zero emission vehicles.

Davis's claims were subsequently defended by other scientists doing further analyses,[18] and these findings were criticized in turn for poor methodology and technique by the original skeptics.

[11] TTX, which blocks sodium channels on the neural membrane, produces numbness, slurred speech, and possibly, paralysis or even respiratory failure and death in severe cases.

As an isolated pharmacological agent, it is not known to produce the trance-like or "mental slave" state typical of the zombies of Haitian mythology, or of Davis's descriptions.

He and his wife, Gail Percy, have lived in several places, sometimes with concurrent residences in Washington, D.C., Vancouver, the Stikine Valley of northern British Columbia, and Bowen Island.