The Starchild Skull is a 900 year old skull that resembles a deformed human, but has a variety of features that indicate it is not human at all. In 2004 a group of experts led by Dr. Ted Robinson, a renowned surgeon, studied the skull in deatil. They concluded that it could not be any known deformity, and that it might not even be human.

The most striking features of the skull include the very thin, light, strong bone, the shallow eye sockets, the lack of an inion, and the shape of the cranium. 

DNA testing is ongoing, and although a small amount of human DNA was recovered from the skull in 2003,  the results left open the possibility that other, non-human DNA within the skull was yet to be recovered.