Washington DC, July 26 -- Researchers say a tiny one-eyed ancestor that lived nearly 600 million years ago may have shaped the evolution of every vertebrate eye, including our own. They also found that its ancient median eye lives on today as the pineal gland, which helps synchronise our sleep with daylight.

Humans and every other vertebrate may share an astonishingly strange ancestor: a tiny creature with a single eye centred on the top of its head.

Recent research from Lund University and the University of Sussex proposes that the earliest ancestor of vertebrates passed through a cyclops-like stage nearly 600 million years ago.

According to the researchers, this animal's central eye eventually contributed to the development of the pa...