Whenever two organisms of different species exist in close physical contact to the benefit of both organisms, that's symbiosis. Symbiosis can occur between animals, plants, fungi or any combination thereof. Each organism contributes something that benefits the survival of the other, and in turn receives a survival benefit of its own.
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Clown anemonefish and sea anemones have a mutually beneficial relationship.
Symbiotes aren't cartoon animals living and working together in perfect harmony. Most symbiotes have no idea that they're helping another creature. They're just surviving in whatever way works best for them, an instinctive behavior driven by natural selection.
You probably didn't realize that you're a symbiote yourself. Or that life on Earth probably wouldn't exist without symbiosis. Or that symbiosis might have been responsible for the evolution of multicellular life. Or that some scientists think the entire planet is one giant symbiotic organism. Sometimes symbiosis is pretty weird. We'll explore the weirdness (and maybe find out that it's not so weird after all) in this article.
The algae absorb sunlight through the worms’ clear skin and photosynthesize food -- enough food that the worms have no functioning digestive tract or even working mouths. The algae even recycle the worms’ waste products, and go through entire life cycles inside the worms’ bodies. |
