It turns out Neanderthals were smarter than originally thought.

Kansas University announced Wednesday that researcher David Frayer discovered that some Neanderthals were cognitively advanced enough to make jewelry. Frayer published the discovery in collaboration with three Croatian archaeologists in the journal PLOS ONE.

Frayer said he and his co-authors came to the conclusion by examining eagle bones found over 100 years ago at a Neanderthal archaeological site. Scientists previously had not identified markings on the bones that showed Neanderthals had cut and polished them to fashion them into jewelry.

Frayer said the discovery shows that Neanderthals had much greater cognitive and technical ability that previously thought. Frayer said the more humans discover about Neanderthals, the more sophisticated they appear.