A lizard that lived 48 million years ago is the only known jawed vertebrate with four eyes. Credit: Smokeybjb, via Wikimedia Commons
Extinct lizard had four eyes - short science news - paleontology news

Saniwa ensidens, a fossil lizard, is the first jawed vertebrate known to have four eyes. A team of researchers showed evidence that this extinct species had two extra photosensitive organs: the pineal and parapineal glands. Although they function differently than normal eyes, these organs are able to sense light. For example, they can determine the polarization of light (helping with orientation) and play roles in circadian and annual cycles. Some species living today (fishes and frogs) possess a pineal gland and this study will help scientist understand how it evolved and what is its functions.

Read the full story: Sciencemag
Scientific publication: Current Biology