Board Thread:Theories and Speculation/@comment-26889573-20151008053113/@comment-1872728-20151015190442

LegionZero wrote: Rinnesharingan was a result of the Shinju. Not just purely Shinju, because Shinju doesn't have the eye. Plus, it's a plant, it's not meant to have an eye. Also, the eye "was first manifested on Kaguya as a third eye on her forehead after eating the Chakra Fruit of the Shinju". (http://naruto.wikia.com/wiki/Rinne_Sharingan)