At the southernmost tip of South America, where the Andes taper to a few small rocky islands in the midst of continual storms and turbulent seas, there once lived a people, only recently become extinct, who may have been the most wretched and benighted to have survived into modern times. The Yahgans, a pygmoid strain of American Indians, lived without clothing or any shelter but windbreaks formed of fallen tree branches heaped with grass. They protected themselves against the subantarctic cold by huddling together in the mud. They did not farm or keep domestic animals; they had no oral history, no myths, no complex social structures, no moral codes. They were cannibals. They asserted their humanity, in a cultural sense, only in the possession of fire, language, and a few primitive tools.
In 1830, the Beagle, an English ship under the command of 24-year-old Captain Robert FitzRoy, anchored off Tierra del Fuego. One of its whaleboats was stolen and disassembled by Yahgans, who reacted to unusual objects, like clothing or boats, by ''ripping them into progressively smaller pieces'' in a spirit of ''wild hilarity.'' FitzRoy took four hostages to force the return of the stolen boat. But hostage-taking was not an idea Yahgans understood, so FitzRoy decided to bring the four back with him to England, civilize them there, and then replant them among their people, along with a couple of missionaries. Thus began a Victorian comedy of terrors every bit as gory, melodramatic, and blackly hilarious as that of the Demon Barber, Sweeney Todd.
The three men of the book's title are Captain FitzRoy; Jemmy Button, the brightest of the Yahgan hostages (and eventually the book's tragic hero); and Charles Darwin, who accompanied FitzRoy as a kind of free-lance botanist and whose own chronicle of the voyage of the Beagle is one of the classics of scientific literature. Richard Marks, the author of two novels and a play, doesn't quite succeed in braiding Darwin's oft-told life story into the more lurid chronicle of the Yahgans and the doomed efforts of a succession of English missionaries who tried to bring the fruits of civilization to a people who preferred meat.
Yet the theory of evolution is given a keen edge in this context, for the Yahgans do seem to have been culturally, if not biologically, something like a missing link between Homo sapiens and earlier primates. In their starry-eyed efforts to bring spiritual values to the Yahgans, the missionaries were, in their own way, contesting Darwin's dismaying hypothesis, for the Yahgans seemed living proof that man, in his natural condition, was a brute beast.
Three Men of the Beagle is like one of those ''lost continents'' of pulp fiction, populated by cavemen and dinosaurs, with the wonderful difference that it isn't fiction. A-