But McCandless went deeper and darker than any of those American icons, and perhaps he was mad, in the Kerouac sense.

BBC: Call of the wild

It tells the true story of Christopher McCandless, a soulful young product of a good college and a solid middle class family.

BBC: Call of the wild

In one sense, McCandless was no different than Thoreau at Walden Pond, or Huck Finn in his raft on the Mississippi, or Jack Kerouac on the road.

BBC: Call of the wild

At director Penn's urging, the Los Angeles-raised Hirsch ("The Girl Next Door, " "Lords of Dogtown") stayed true to McCandless' spirit throughout filming, to the point of losing more than 40 pounds off his already slight, 5-foot-7-inch frame.

CNN: 'Wild' time for future 'Speed Racer'

According to the journal discovered with his body, McCandless had tried to hike out after three months but had found his way blocked by the swollen waters of the Teklanika River, which had risen dramatically since he forded it on his way in.

BBC: Journey into the Alaskan wild

Dr. Yoshikawa received the Boyd McCandless Award for early career contributions to developmental psychology from the American Psychological Association, and has served on the Board on Children, Youth and Families of the National Academy of Sciences as well as the U.S. Department of Health and Human Services Advisory Committee on Head Start Research and Evaluation.

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