In an interesting scientific discovery, a 400,000-year-old link to our human origins has been discovered in Spain.  

According to the scientific journal Nature, hominim (our earliest two-legged ancestors) bones were found in a pit called Sima de los Huesos in northern Spain. But rather than clarify our human origins -- scientists originally thought we were descendants of the Neanderthals -- this discovery has actually raised more questions than answers. 

Per the New York Times, this discovery has lead scientists to believe that the earliest human ancestors were an enigmatic group of hominims called the Denisovans, known only from DNA retrieved from 80,000-year-old remains in Siberia, 4,000 miles east of where the new DNA was found. 

"This would not have been possible even a year ago," said Juan Luis Arsuaga, a paleoanthropologist at Universidad Complutense de Madrid and a co-author of the paper.

Finding such ancient human DNA was a major advance, said David Reich, a geneticist at Harvard Medical School who was not involved in the research. "That's an amazing, game-changing thing," he said. Since the 1970s, Spanish scientists have brought out a wealth of fossils from the cave dating back hundreds of thousands of years. "The place is very special," said Dr. Arsuaga, who has found 28 nearly complete skeletons of humans during three decades of excavations. 

While it's unclear what this latest discovery means for evolutionary science, what is clear is that this discovery will lead to a whole new school of thought when it comes to evolutionary science. Could it be possible that the two species -- the Denisovans and the Neanderthals -- inter-bred? Or is it, as Beth Shapiro of the University of California at Santa Cruz suggested, possible that this DNA belongs to a whole new (and different) line of human ancestors? 

Additional research is definitely needed and will definitely be conducted.