It's an Amazing World

I recently finished my docent training at the zoo, a process of several Saturdays spread out over about 9 months. The very first thing I studied was the aquarium, and much to my delight, we got a behind the scenes tour, so we could know how everything operates. It really was like going behind Oz's curtain. There are a million things I could tell you about but since I'm still glazed over from the holidays, I will pick a simple one.

We were making the rounds of tanks -- from sharks to sea turtles to nautilus when I stumbled upon this sight on a shelf at the very end of the aquarium hall.


There, suspended in this clear lucite circle, were delicate, transparent jellyfish. It's so hard to believe these ghostly whisps are living beings with organs, instincts, the ability to collect food and reproduce. Yet they have no bones, heart, brain or eyes. While they may use their tentacles (with little stingers) to find food, they must also use them in lieu of sight, to inuit whatever they run into. But what do they do with no brain to process the information? I don't know enough about this but it seems they default to nerve impulses.

Some jelly fish are swimmers, propelling themselves by a pumping motion they make with their whole bodies; others, like these, float with the currents. I learned that the tank is round because the jelly fish are too fragile to interact with corners. And this orb turned slowly to provide a current of sorts, for them to keep in motion. As I'm sure you can imagine, it was mesmerizing to watch, and so relaxing.

They only live for about 3-6 months. Despite all this, these flimsy beings have great resilience as they've been around for more than 650 million years (which means they've got the dinosaurs beat) and though many species aren't dangerous, their stingers have killed human beings. Impressive, huh?