Marine mystery solved: How anemonefish avoid stings from their sea anemone hosts

The clownfish-anemone living arrangement is one of the most widely recognized examples of symbiosis. Researchers have made a breakthrough in understanding how anemonefish can live safely among sea anemones without being stung by their venomous tentacles, solving a century-long mystery. Scientists have discovered that anemonefish have evolved to maintain very low levels of sialic acid in their skin mucus to avoid triggering the release of nematocysts (stinging cells) in their sea anemone hosts. The researchers found that sea anemones also lack these sugar compounds in their own mucus, likely to avoid stinging themselves. Their findings suggest anemonefish might be using a similar protective strategy to their hosts.