Natures Fascinating Symbiosis

Scuttling silently across the ocean floor, the tiny candy cane stripped legs of the boxer crab extend sideways, reaching for its pebbled home. Unknown to the crab and lurking within, is a hungry predator, ready to make a quick snack of the tiny crab. The crab is not defenseless though, reaching out its two front claws it shakes its ferocious pompoms at its enemy.

Ferocious pompoms? Well, they're not real pompoms, they just look like them. Growing around the crabs front claws are tiny creatures called sea anemones. These sea anemones protect the crab as they contain stinging cells which deter any possible attacker.

Since the boxer crab gains protection from its sea anemone gloves and the sea anemones get a place to live and left over scraps of food from the crab, both of them benefit in their relationship. When two organisms both benefit in a relationship like this, it's called mutualism. Mutualism is one type of symbiosis.

A large beetle spreads its wings to fly revealing a teeny tiny hitchhiker going for a free ride. The pseudoscorpion, spider like and often overlooked due to its small (1 cm) size, often disperses by hiding under the wing covers of large beetles. Not only does it get a lift to a new destination, but it gains protection from predators to boot. The pincers of the pseudoscorpion are too small to affect its beetle host, so the pseudoscorpion gains all the advantage in this relationship.

A symbiotic relationship such as this one, in which one organism benefits and one remains neutral is called commensalism. Commensalism is usually harder to find in nature because as you look closley you often find both species benefit in some way, its just not that obvious at first glance. In this example, perhaps the beetle gets something from the pseudoscorpion, we just don't know what that is quite yet.

Leaping from the edge of a rock face to almost certain death, a grasshopper plunges into a pool of water where it drowns. Suicide? Hardly. Inside the entire body cavity of the grasshopper except its legs and head, squirms a tiny hairworm. Upon arrival in its grasshopper host, the worm secretes a chemical cocktail that wreaks havoc on the grasshoppers central nervous system causing it to eventually take the final plunge. When the grasshopper hits the water, the hairworm, now three or four times longer than the grasshopper, can swim away and join its fellow hairworms in a giant writhing mass where it will breed.

The hairworm is a parasite and gains all of the benefits in this symbiotic relationship, called parasitism. Usually the parasite does not kill its host, making this example unique. There are hundreds of parasites out there, many feeding off of human hosts.