One of Odysseus’ less than pleasant encounters during his wanderings was with a Cyclops. There were supposedly three giant sons of the sea god Poseidon, with only single eyes in the middle of their foreheads. They also were said to have the bad habit of eating people and the Cyclops who held the wandering Greeks captive was said to have dined on some of Odysseus’ men. The rest were only able to escape a similar fate by ram-rodding a hot branding iron into the beast’s single eye.

Fortunately, of course, that encounter with the Cyclops was strictly legend. But, as with so many classical mythological creatures, the name Cyclops has been attached to a real animal. And in this case, the modern day Cyclops has become a legend—as well as legion—in itself!

This Cyclops is a member of the crustacean sublcass Copepoda. Copepods are characterized by having a single eye in the middle of their head region. There are thousands of species of copepods—probably at least 9,000, although an exact count is hard to get since most are so small.

But what copepods lack in size they make up for in numbers. It has been estimated that within the span of one year, one Cyclops could potentially have 42 billion offspring!

The mere fact that every bit of the ocean and freshwater bodies of water are not solid packed with copepods indicates that many of these potential billions do not survive. But they do play a pivotal part in any marine or aquatic food web. Copepods are the major consumers of diatoms and other plant plankton. Then they themselves are eaten—en masse—by plankton feeding fishes, whales and other larger animals. It has been stated that many fishing industries, such as the herring industry, are dependent upon the superabundance of copepods.

California Diving News

There are some copepods which are not planktonic. California is home to a free crawling copepod which lives in probably one of the harshest environments on earth—the small pools above the high tide zone.

Here, where the sun baking down and evaporating away the limited amount of water and causing the salinity and temperature to rise to many times that of the sea, alternates with diluting freshwater of rain, the little 1/16 inch long Splash Pool Copepod (Tigriopes californicus) not only copes, but thrives. To the unacquainted observer, this fantastic animal, however, may look like nothing more than a bunch of red pepper seeds moving about.

Amidst the crashing waves of another harsh environment lives one more of California copepods, Pseudomyicola sponosus. This copepod cohabits with the bay mussel (Mytilis edulis), in a commensal type relationship. The crustacean stays cozily tucked inside the mollusk’s mantle cavity, while the bigger protector pumps in plankton rich sea water for them both to eat.

Nevertheless, this relationship can go beyond just not in such a friendly arrangement, and become a downright parasitic one. Actually, there are thousands of species in this category. Some, like the one associated with the bay mussel, attack mollusks, but the majority have a preference for marine fishes. None, however, like those three mythological Cyclops monsters, eat people.

In all their various forms, it has been speculated that there are more individual copepods than all over multi-celled animals on earth combined! So it is a good thing, then, that the modern day Cyclops and all its copious cousins are only giants only as regards their numbers and ecological value, and NOT their size!

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