Complex sentence: The Starchild skull is part of a malformed human skull which paranormalist Lloyd Pye has claimed is of extraterrestrial origin, likely to have been that of a male child who died as a result of congenital hydrocephalus.
Split into simpler sentences: The Starchild skull is part of a malformed human skull which paranormalist Lloyd Pye has claimed is of extraterrestrial origin. The skull is of a male child who was likely to have died as a result of congenital hydrocephalus.