The Cave That Rewrote History

追加: 2026-06-01

[00:00:06]This is Piki Machai Cave. It's at the top of a very steep Peruvian hill at an altitude that made getting here feel honestly like a bit of an endeavor. But it was worth it because at the top here is a genuine world wonder. When I filmed this episode, this cave was the oldest known inhabited place in the Americas.

[00:00:27]And not only that, it was dramatically older than anywhere else that had ever been found on either continent even. It was here in the 1960s where a scientist by the name of Richard Mcnish rewrote history. In the back of this cave, he found evidence of human habitation going back to a preclois era. That means 15,000 plus years ago, long before anybody should have been in the Americas, let alone Peru. And what's more, he didn't find the evidence along the coast. He found it here, high in the mountains at altitude. And that implied so many more generations before them.

[00:01:09]The people who found this cave would have already been on this continent for a while. It was a truly unbelievable discovery. In this cave, that scientist would find 12,000year-old bones of prehistoric horses, elephants, llamas, and cats, all coralled here by some force, perhaps a human hand. An entire ecosystem of huntable fauna collected together in a single corner as if to show intent. But the most prevalent by far were the bones of the sloths. And I'm not talking those little guys in the trees, but rather the famous ones that we eradicated almost as soon as we'd met them. The Milo Dante, the skilled dothetherreium, the irriorium.

[00:01:58]I probably said those wrong. According to the evidence that Mcnish found, if you can pardon the pun, this cave was likely a sloth house. A place where those giant extinct beasts would have had their bones turned into tools. And then, like the dodo, these giants of this cave would have all been eaten to the very last. Their femurss turned to hammers, needles, axes, and spears.

[00:02:26]But the most interesting part was that those slothbones weren't 12,000 years old like the horses. They were 20, maybe even 25.

[00:02:39]And yet somehow they too had signs of human interaction. They too had been made into tools. Humans were here at a time when they really shouldn't have been. In finding these scraps from those unknown craftsmen, Mcnish had reset the timeline of our entry into the Americas back at least 10,000 years, which just for reference, the first Egyptian pyramid was built less than 5,000 years ago. So if you think that's a long time, this would have been double.

[00:03:16]And had I made this video before March of this year, that would have been the story that I told you because that's what the evidence suggested. But as it turns out, being meticulous and thoughtful like Richard Mcnish doesn't necessarily mean you're right. The best practices of the 1960s are not the same as today. And just as I was starting to write this episode, researchers returned to those bones and made some entirely new conclusions. As it turns out, it only looks like humans interacted with giant sloths in this cave 25,000 years ago. But that's probably not what actually happened. What's more likely is that the roof caved in and pushed some of those newer sloth bones down among the older ones. And since in the 1960s, one layer of soil would often be treated as one block of time, it was just presumed that if you could date any of the bones within a single strata, you could guess that the others were roughly the same age. And that was especially true in situations like this one where only a single bone was capable of being dated at all. It wasn't like Mcnish was trying to deceive people. He wasn't even actually lying, at least not deliberately, because he had no way to know that he was wrong. He did perfect research for his time. But he was wrong.

[00:04:34]Or at least that's the new presumption anyway. Humans did interact with sloths here, though. was probably still a sloth house. There's just no reason to suspect any of this evidence is pre-Clovis. It is a special cave. It's still 12 to 15,000 years of human activity. We still carved those bones. It's just no more special than any of the other caves that offer similar insights all across Peru.

[00:05:00]So, with all of that said, I got to say thank you to the scientists because that was really timely of you. I almost made that first episode. And yet at the same time, I'm happy you held back. I'm happy that I didn't know this before I visited because then I might not have visited.

[00:05:18]And despite how out of breath I was and how embarrassing it is climbing up a hill at that altitude, I do think it was worth it. It was worth it to stare at that view and think back to hundreds of generations ago, to think back to the sloth pokers.

[00:05:33]And that's a whole lot easier when you're standing at the mouth of their cave.

[00:05:38]And really, regardless of the depths of history here, 25,000 years, 15,000, I personally get the same chills either way. And no matter when they first arrived, at some point some ancient explorer that we will never know walked in here with a stick, poked a sleeping giant in the heart, and then sat down to carve its bones into needles.

[00:06:09]That's what it took to make us.

[00:06:15]This is rare earth.