What Good are Jellyfish?

There are several creatures that we wonder why God made them. You cannot saddle them up, eat them, keep them as pets, and many seem to be more harm than good. But if you study up on them, you can find that they are indeed a part of the ecosystem in ways we did not know before. If more researchers took the view that each organism was created for a purpose instead of taking an evolutionary approach (research was tainted by evolutionary thinking in a turtle sex selection study, for example), I suspicion that more answers would be found more rapidly.

People may be surprised to learn that jellyfish do serve a purpose in the ecosystem.
Credit: NSF / Henry Kaiser
One such critter is the jellyfish, some of which have deadly stings. (They have no nervous system or brains, but their very basic nerves in the tentacles are their sensors.) When people are aware of jellies, they are wise to get away. (I read that some people eat them, but didn't cotton to doing the research.) Sure, they look nice, but do they serve a purpose besides that. I'll allow that jellyfish are mighty difficult to study (can't rightly tag them for tracking), but some research has yielded surprises.
If you needed a perfect ocean villain, you’d be hard-pressed to find something more difficult to track and capture than the jellyfish. The most well-known types are essentially bags of water with stinging tentacles. They eat constantly, they reproduce in overwhelming blooms that choke the seas, they turn a morning swim into a painful, goopy experience, and they don’t seem to contribute much to the balance of ocean life.

At least, that’s how researchers used to view them.

You see, the problem with studying an organism with the consistency of slime is catching it and tracking it. With fish, you can just drop a net in the water and scoop them up. You can tag sharks and track where they roam. Larger, boney animals show up in the stomachs of other marine life, if you care to look (and lots of scientists do).
To read the whole article, click on "Terrors or Treasures?" Bonus fun fact: a group of jellyfish is called a smack.