In 1889, William Bateson observed in detail the way that decorator crabs fix materials on their backs. He noted that “the whole proceeding is most human and purposeful”, and that if a Stenorhynchus crab is cleaned, it will “immediately begin to clothe itself again with the same care and precision as before”.



See them in action to see how they do it! :D
https://youtu.be/OwQcv7TyX04