Leave your feedback Share Copy URL https://www.pbs.org/newshour/show/uncovering-ancient-human-fossils-at-sima-de-los-huesos Email Facebook Twitter LinkedIn Pinterest Tumblr Share on Facebook Share on Twitter Story Researchers excavate ancient human skeletons from a "pit of bones" at Sima de los Huesos, an archaeological site in the mountains of Northern Spain. These fossils have given scientists new clues about the evolutions of humans and how our ancestors bred with other ancient human species. Watch Watch the Full Episode PBS NewsHour from Dec 04, 2013