Lived 550 million years ago.. The oldest animal with a head showed a preference for its right side

- If you use your right hand for writing or performing your daily tasks, the roots of this trait may trace back to a worm-like creature that lived about 550 million years ago and tended to bend to the right. This creature, known as "Spriggina floundersi," appeared in the seas of the Ediacaran period, which lasted from 635 to 542 million years ago.