Individuals that live in microhabitats that are deficient in photosynthetically active radiation (PAR), such as under docks or in caves, lack symbionts and are pale yellow to white in color.

As adults, aggregating anemones release gametes into the water that join to form genetically unique individuals that settle on intertidal rock.

This restricts the symbiotic organism to euphotic habitats and requires consistent exposure to high levels of ultraviolet radiation (UVR).

To protect from potentially damaging UVR, the algae provide mycosporine-like amino acids (MAAs) that act as sunscreen for themselves and the host.

[10] The anemones, in turn, produce antioxidants called superoxide dismutases to protect against reactive oxygen that causes oxidative stress.

When a polyp makes physical contact with a non-clonemate, it extends the acrorhagi to attack the competing anemone with stinging cells called nematocytes.

As water rushed into the tank, warrior polyps inflated their acrorhagi, tripled their body length and began reaching into an empty swath of rock between the colonies.

[13] The few known predators of the aggregating anemone include a species of nudibranch (Aeolidia papillosa), leather star, and mosshead sculpin.