Jellyfish (or as some people call them jellies because they aren’t fish) truly do go with the flow. Most drift on natural currents to get around (though some do pulse swim). You won’t hear them singing “If I only had a brain” or “If I only had a heart,” because they have neither and seem to do fine without them. They have no eyes, just light-sensitive organs, nor bones either.
But before you start feeling superior, don’t forget they’ve been on Earth for a l-o-n-g time. When we humans were ape-like creatures hanging from from trees, they had already been on Earth for 649 million years.
Here’s a Lion’s Mane Jelly Dance from an exhibit at the Monterey Bay Aquarium: