Scuba diving opens a door to world that is beautiful beyond description. It is a nearly soundless world of peace and tranquility. And at times, it is a world full of mystery and danger. It is a delicate balance that can change in an instant.
The animals in this underwater domain are bizarre and fascinating. They have adapted in surprising ways to help them find food and also to help them avoid becoming food. This upside jellyfish has not been understood until recently. It has adapted to produce stinging cells, like most other jellyfish. These cells inject venom and immobilize prey, similar to other jellyfish. But what makes them different is that they secrete a mucous that is filled with tiny cell masses that are equipped to deliver this sting. They obtain nutrients in several ways. They enjoy a symbiotic relationship with the algae that grows within them. They also feats on brine shrimp and other tiny creatures that swim through the water.
The upside down jellyfish releases balls of mucous that researchers describe as "potent little grenades". Separated from the jellyfish, these cells can survive for up to ten days. They sting any creature that comes in contact with the mucous. These cells are called cassiomes. The jellyfish can then draw the mucous back in and feed on the dead or paralyzed organisms.
Originally, researchers who were studying these animals described stinging sensations and referred to it as "stinging water". It was only after closer inspection that they learned that the floating mucous had been released by these upside down jellyfish.
The ocean is still largely a mystery to us and we are only beginning to understand the creatures that live there.