Dr. Lavey's unrelated fieldwork in Nepal led to the discovery of a landslide about 800 years ago. He found evidence in rock samples and satellite imagery, suggesting that landslides, along with glaciers, are responsible for shaping mountains. Landslides act like sandpaper, reaching areas glaciers cannot.
Little is known about why he fled across the border into the hermit kingdom, but securing his release will require some tactical diplomacy. Given the tense relationship between both countries, is Kim Jong Un prepared to come to the table? A look at research which suggests gold might not always be an effective hedge against inflation (08:52). And, why mountains stop growing (15:42).
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