Jellyfish are among the most fascinating (and unique-looking) creatures of the sea! Did you know that these ancient invertebrates have been around long before dinosaurs roamed the Earth—more than 500 million years ago? Even though jellyfish have one of the most basic nervous system in a multicellular organism, they are able to produce toxic venom, emit light and may even hold the secrets to immortality.
Read more on Ocean Conservancy's website.