Aeolidia' s digestive tract is lined with a protective coating to prevent injury from any unexploded nematocysts it consumes. Sea anemones also use their poisonous stings against their own kind, usually while competing for territory. Some species even possess special clublike structures, packed with potent stinging capsules, that they use to battle other anemones. Territorial fights often result in serious injury and even death to one or both anemones. Many sea anemones can clone themselves -a useful trait when you are stuck to a rock with no members of the opposite sex nearby.
Some species break off a small part of their base, which then grows into an adult anemone.
Both of these methods result in two genetically identical animals where once there was one. A small intertidal anemone known as Anthopleura elegantissima is a master of cloning. A single anemone will clone itself many times, creating large aggregations of genetically identical anemones. As the colony expands, it may run into another colony of different genetic makeup. When one colony encroaches on the territory of another, the anemones on the periphery engage in battle using bulbous clubs full of nematocysts to sting the enemy.