Saturday, January 16, 2010
Sea Squirts under the pier, Mission Bay. Sea Squirts are Tunicates, underwater sack-like filter feeders. These were growing on a rope under the pier. When the rope was lifted out of the water, they all squirted out water like a little squirt gun and then sealed shut, ending up looking like masses of brownish jelly. I suppose that is how they got the name sea squirt. Ironically, they are classified in chordata (very primative vertebrates, apparently). According to Wikipedia, Tunicates "evolved in the early Cambrian period, beginning c 540 million years ago. Despite their simple appearance, tunicates are closely related to vertebrates, which include fish and all land animals with bones."
Some sea squirts are spreading their range aggressively and are listed as noxious pests (these CA Sea Squirts are apparently spreading up into Washington, for example). Oh, it would be such a drag (literally) to have to clean those off the hull of a boat, wouldn't it?