In the summer of the 1992, a 24-year-old named Chris McCandless died in his camp in the Alaskan wilderness.
Several months earlier, McCandless had walked into the wilderness for a final great adventure after wandering the United States having given away all of his possessions.
That summer, in Alaska, McCandless camped in the shell of an old bus and subsisted on animals he hunted and plants he foraged. For several months, he thrived. But then something went wrong. In mid-September, McCandless's body and diaries were found by hunters. The assumption was that he had starved to death.
Jon Krakauer wrote a story about McCandless for Outside Magazine, and then a famous book called "Into The Wild," which was later made into a movie.
Krakauer had a lot of sympathy for McCandless. In "Into The Wild," he portrayed him as a smart, adventurous, and capable — if devoutly idealistic — young man.
Many of Krakauer's readers, meanwhile, thought McCandless was a fool — a dreamy kid woefully unprepared for life in the wilderness who, in a sense, had gotten what was coming to him.
But how had McCandless died?
Had he really starved to death, despite being able to hunt and gather food?
In "Into the Wild," Krakauer speculated that what had killed McCandless was not actually starvation but wild potato seeds. McCandless had eaten lots of these seeds, and Krakauer speculated that a toxic alkaloid in the seeds had so weakened him that he had been unable to gather enough food.
But wild potatoes are described in most guidebooks (including McCandless') as a non-toxic plant. So Krakauer's "toxic alkaloid" theory was ridiculed. Krakauer sent some seeds to a professor for tests, but the professor couldn't find any toxic alkaloids.
Krakauer was confused. But he didn't give up.
And, now, 21 years after McCandless's death, Krakauer thinks he has finally found the answer.
A researcher named Ronald Hamilton had written a paper arguing that McCandless had, in fact, been killed by the wild potato seeds, but not because of any "toxic alkaloids." Rather, Hamilton argued, McCandless's meager diet and malnutrition in the wilderness had made him susceptible to a rare but brutal affliction called "lathyrism" that gradually paralyzes its victims. Lathryrism occurs primarily in malnourished young men, and it is caused by the ingestion of an amino acid that was first discovered in the seeds of wild grass peas.
After reading Hamilton's paper, Krakauer sent a bunch of wild potato seeds to a chemist. The chemist found that, indeed, the wild potato seeds contained the amino acid that causes lathyrism.
So Chris McCandless may indeed have died of starvation, Krakauer concludes, in a long article in this week's New Yorker. But he starved not because he was alone in the wilderness, but because an amino acid in a plant that his guidebook had told him was safe had gradually paralyzed him. Once McCandless could no longer move, he could no longer gather more food. And, shortly thereafter, he died.
As Jon Krakauer notes at the end of his article, Chris McCandless would now be 45.
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