Christopher Darwin's great-great-grandfather Charles espoused the theory of evolution. Christopher's grandmother had a philosophy of her own. "If you can't be first," she'd say, "at least be different." It is advice Christopher has learned to live by.

Although he was enrolled at Oxford Polytechnic, Darwin, who grew up in London, spent much of his time with the Dangerous Sports Club at Oxford University. The youth who had failed biology proved an ace at jumping off cranes, secured only by a piece of elastic just long enough to keep him from hitting the ground. After graduation, as a publicity stunt for a rock band, Chaz, as he is called, dressed up like a turkey and jumped—unsecured—from a bridge over the Thames.

This year Darwin, 28, is taking his daredevilry to new heights. Last March he and three friends, all in tuxedos, sat down to a luncheon of cucumber sandwiches and grilled trout while dangling 250 feet above the harbor in Sydney, Australia. That was the dress rehearsal. This week Darwin is leading a party of seven friends, four mountaineers and several llamas—a group he has dubbed the Social Climbers—to the 22, 205-foot summit of Mount Huascarán in Peru. Upon arrival the group will change into formal dress (accessorized with crampons and ice axes), be seated at a suite of faux Louis XIV furniture (made of carbon fiber and foam) and begin what Darwin calls "the highest black-tie luncheon party on earth."

Darwin, who gave up his job as a TV-commercial producer in Sydney to oversee the event, says he does these things because "they're challenging and fun." But like his illustrious ancestor, he is concerned with the fate of the species: If the Peru climb goes as planned, it will raise $80,000 for Australia's National Heart Foundation.