ARI SHAPIRO, HOST:
A mother carrying her child is not news, but 10,000-year-old footsteps of a mother carrying her child that go on for nearly a mile - that's a big deal. And that find at White Sands National Park in New Mexico has archaeologists very excited.
AILSA CHANG, HOST:
Now, White Sands looked a lot different 10,000 years ago. Instead of endless sand dunes, there was plenty of water and plant life. Huge, now-extinct animals like woolly mammoths, giant land sloths and American lions roamed the area.
SHAPIRO: And humans interacted with them, as evidenced by the prints they left behind.
DAVID BUSTOS: You can see places where there's a giant ground sloth that walked by in a puddle, made the puddle larger. It looks like these big steps of giant ground sloth. But then you see children were jumping inside the puddles that were created. You'll see all kinds of little prints of children jumping around, hundreds of prints.
SHAPIRO: David Bustos is the park's resource program manager and part of the research team. He says there are older fossil human footprints in the world but none that travel this far.
CHANG: And the story these tracks tell are of a woman or young man carrying a child in a hurry.
BUSTOS: And not only that, but they were slipping a lot with every print, with every step. It was very wet, so there was a lot of slippage that you could see within each print. It must have been quite a story they had to tell at the end of the day.
SHAPIRO: Bustos says now that these prehistoric tracks have been exposed, they will soon blow away. But the details uncovered by their discovery will inform history for generations to come.
(SOUNDBITE OF THE BAD PLUS' "GOLD PRISMS INCORPORATED") Transcript provided by NPR, Copyright NPR.