It's Unexplainable. I'm Noam Hassenfeld.

For most of human history, which goes back hundreds of thousands of years, our past has

been close to a black box.

Fossils and archaeological evidence tell us a little about the deep past.

Carbon dating can tell us about a rough age of something, but altogether the story they tell

is incomplete.

Then, just about a decade ago,

scientists came up with a new tool. After drilling into 40,000-year-old bones, they were finally able to sequence the entire genome of an ancient person. This was an earthquake. All of a sudden,

there was a brand new way of analyzing our past,

our extremely ancient past, and it gave us a huge amount of new information. But it also

just blew up a lot of what we thought we understood. Over the last decade, it's forced scientists

to rewrite a wide swath of history. We produced an episode on one of these rewrites early last year, and it's forced scientists to rewrite a wide swath of history. We produced an episode on one of

these rewrites early last year, and it's one of our favorites, so we wanted to share it with you

this week. Just a heads up, there are some swears in the second half of the episode, so if you

want a bleeped version, you can find one in our clean feed over at vox.com slash unexplainable.

This historical rewrite starts near an icy lake in the mountains of northern India, and as

researchers have continued to examine it, they've generated even more questions.

Douglas Preston reported on the rewrite for the New Yorker.

Well, in 1942, an Indian Forest Ranger was following a herd of rare antelope very high up in the Himalaya Mountains.

And he came across something incredible.

He came across a lake at 16,500 feet amidst glaciers and barren peaks.

The lake was called Rupkund.

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