Most decorator crabs belong to one of eight families in the superfamily Majoidea, commonly referred to as spider crabs. About 75 percent of the group’s more than 1,100 global species mask their presence by wearing disguises made from living organisms scissored from the landscape. They commonly hijack seaweeds, sponges, tunicates, bryozoans and hydroids. The crabs manipulate the purloined pieces of attire with their mouths before attaching them to one of the many fishhook-shaped bristles arranged in rows on the carapace, rostrum, walking legs and claw arms, depending on the species.
Interactions between different species, whether above or below water, typically revolve around confrontations between predators and prey. At the opposite and more harmonious end of the spectrum, a scattering of unrelated species coevolved to form lifelong alliances for their mutual security. These relatively rare go-along-to-get-along partnerships provide a net benefit for both parties, improving each species’ reproductive success. The close living arrangement between weak-eyed alpheid snapping shrimp and sharp-eyed partner gobies is a classic example of symbiosis in the sea.
In 1995, when we first explored wunderpus territory, which overlies much of the Coral Triangle, the then-undescribed octopus’ fame had spread far and wide. The newly sensational creatures attained much of their acclaim for dancing like dandies across sandy seafloors on eight unimaginably limber arms — an eye-popping feat of acrobatic dexterity well worth traveling halfway around the world to see.
