Tuesday, April 6, 2010

Another Story About Symbiosis

Coincidentally, our visitor education update at the aquarium this week was about symbiosis. One of the specific stories is about goliath groupers, huge fish that like to live in blue holes and other close quarters environments and their symbionts the neon gobies. The little gobies are often overlooked by visitors because they are so small compared to the groupers. But I was able to draw several visitors' attention to the little fish. They like to hang out right on the grouper itself and munch on parasites, dead skin and other junk the grouper doesn't want around. They are one of many "cleaning station" symbionts that exhibit this kind of behavior: the cleaner gets a meal and the cleanee gets...cleaned.

Some thought the very fact that this big fish had several little fish living on it was interesting on its own but these symbiotic relationships are also a great way to show, as I have said, that the natural world is an ecology. The removal or depletion of a single species can have far-ranging effects beyond what we might first think.


  1. I always think back to my ecology class days when I hear about symbiosis. I think it is helpful/interesting to make the distinction between symbiosis and mututalism. Symbiosis, as you described, refers to when one organism lives within another, and their survival may be mutually dependent. Examples - coral and zoxanthellae, termites and the bacteria that live in their guts and allow them to digest wood. Lichen (fungi and algae) are also an example.(I was interested to learn that the algae dont necesarily depend on the fungi to survive!). A mutualism occurs when organisms live separately but interact in closely-tied, mutually beneficial ways. Under this definition the groupers and cleaners would be a mutualism, as would the fmaous example of anemones and clownfish. I guess people in general just use the term symbiosis for all of it, but I think there's a useful distinction.

  2. From what I understand from reading up on it and talking with folks at the aquarium is that symbiosis refers to any and all relationships between two organisms where at least one benefits from the interaction. This can either be internal or external, so close that they are almost treated as one organism (in the case of corals and lichens) or seemingly entirely separate organisms like the grouper/gobie pair or the clown fish/anemone pair.

    The distinction of mutualism refers, from my understanding, to a symbiosis where both organisms benefit. This is then contrasted with commensialism (where only one party benefits) and parasitism (where one benefits and one is harmed). I found it very interesting that parasitism is technically considered a subtype of symbiosis because I tend to think of symbiosis under the beneficial terms.