Feb 4, 2009

Box Jellies

Most jellyfish are considered plankton -- that great amalgam of free-floating flora and fauna that is the foundation of the oceanic ecosystem. But not so with the box jellyfish. These jellies are hunters. They are active swimmers, are able to negotiate obstacles, and can make a rapid 180-degree turn. How do brainless creatures hunt and avoid obstacles? With 24 eyes that give them a view in literally every direction (not just 360, but up and down as well).

Photo credit: Anders Garm
It's one particular set of eyes that are so fish-like in their lens composition that they can discern shapes and color. It's that pair of eyes that you see to the left. Imagine swimming up behind one, only to have it spin around and stare you down. And stare you down is right, because you'd be best served by fleeing.

Box jellyfish are counted among the most lethal of animals to humans, as thousands of Australians have been killed over the past 50 years after encountering the jellies' stingers. And if the sting doesn't kill you, you're still left with excruciating pain. Lovely. Most of the jellyfish I encounter come in the form of lifeless gelatinous lumps in the sand. If I ever get to live out my dream of diving in Australia, I'll need to keep these monsters in mind.

Thanks for the box jellyfish, Rebecca.

7 comments:

Sabina E. said...

That's pretty awesome.

Alison said...

Awwww, it's cute! It looks like the one in Finding Nemo!

Wombat, if you haven't already, you need to read Bill Bryson's In a Sunburned Country. You will find no better description of the agonizing pain these little suckers can inflict. Plus, he makes it funny.

W. A. Whipple said...

They're a fairly common nuisance in Hawai'i, too:
http://www.hawaiiforvisitors.com/nature/box-jellyfish.htm
http://www.aloha.com/~lifeguards/jelyfish.html

(One more reason to go hiking instead of swimming...)

Anonymous said...

You'll also need to worry about these: http://en.wikipedia.org/wiki/Irukandji_jellyfish

Anonymous said...

If Frank Herbert's ideas about harsh environments being the ideal breeding grounds for a society of fierce warriors then australians are pretty much the fremen of earth. what the hell is wrong with that continent?

Anonymous said...

Things I have learned as a child: Don't put things up your nose. Cats don't like getting wet. And, "FOR THE LOVE OF GOD, DON'T POKE JELLYFISH!"

So after said lessons were learned, to this day I cannot help but feel this overwhelming urge to throw an entire bucket's worth of sand on every jellyfish I see washed ashore.

Anonymous said...

Don't forget the blue bottles. Ok, so they're not lethal but still painful if you get tangled up in one!

With the amount of nasties we have here in Australia, it's a wonder any of us are still alive!!!!!