5. Boxer Crabs and Their Anemone Pom-Poms: Nature’s Tiny Cheerleaders
Few interactions in the complex realm of coral reef symbiosis are as aesthetically arresting or functionally distinctive as that between boxer crabs and their microscopic anemone “pom-poms.” Boxer crabs, sometimes known as pom-pom crabs, carry a small sea anemone in each of their claws and wield them like a pair of boxing gloves or cheerleader’s pom-poms. The anemones as well as the crab gain from this uncommon alliance. For the boxer crab, the anemones have several uses. Mostly they serve as a defence strategy; the crab waves the anemones at possible predators when threatened, deterring with their stinging cells. The anemones also help the crab find food. Little particles and organisms caught as they brush against the tentacles of the anemones are subsequently eaten by the crab. The anemones get movement and access to food supplies they wouldn’t normally come across in return. The way this relationship is sustained adds even more intrigue. Losing one of its anemones, a boxer crab will actually divide the remaining one in half so that each portion can rebuild into a whole anemone. This guarantees always a pair for the crab. The crabs depend so much on this relationship that, should it be required, they will even steal anemones from other boxer crabs. This symbiosis highlights the amazing adaptation of marine life as well as the sometimes surprising forms that mutually beneficial interactions can produce in the varied surroundings of a coral reef. It is a perfect illustration of how evolution may produce extremely specialised and reliant interactions between species, hence supporting the intricate network of life in reef environments.