Sunday at the Beach with Dr. Todd E.A. Larson: The Ostracod

Is there anything more full of wonder than a child at the beach? Underneath the waves is an entire world waiting to be discovered. Join us every Sunday for a day at the beach, and learn more about the aquatic world!

Fish that shoot laser beams? According to this article it's brought about by one of the most spectacular defensive displays of any creature in the ocean.



Actually, it's not the fish that produces this bioluminescence, it's a tiny flat crustacean known as the ostracod. Certain species of ostracods produce luminescent chemicals commonly called "blue sand" or "blue tears" and when eaten by certain fish, like the translucent cardinalfish above, these ostracods release this glowing chemical in order to attract predators so they won't be preyed upon any more. The cardinalfish, sensing how dangerous it would be to be lit up in a totally darkened environment, spits out the ostracod, resulting in the fireworks above.



A typical ostracod.

Another example of the supreme coolness of nature!

To learn more about ostracods, click here.

-- Dr. Todd

Sunday at the Beach with Dr. Todd E.A. Larson: The Bobbit Worm

Is there anything more full of wonder than a child at the beach? Underneath the waves is an entire world waiting to be discovered. Join us every Sunday for a day at the beach, and learn more about the aquatic world!

The water world is a brutal one; every angler has a story about how they have pulled a small fish toward the boat only to have it struck by a larger one on the way in. It's a fish-eat-fish world out there.

It's also a worm-eat-fish world, too. Enter the Bobbit Worm, a nasty ocean bottom dweller that grows to NINE FEET in length and with a mouth so powerful it can snap a fish in half. And it's a better angler than you are!



It's a monster from a science fiction tale, that's for sure. In 2009, a British marine museum was alarmed by the disappearance of fish and the fact that coral was being sliced in half. They could not find the culprit, so they drained the tank and started to dismantle it when they ran across this:



A Bobbit Worm (only four feet long). They named it Barry, which seems oddly appropriate for a killer fish-eating worm. Anyway, you can read more about the Bobbit Worm by googling its Latin name Eunice aphroditois. And try not to have nightmares when thinking about it!

-- Dr. Todd