Research pair outline status of decorating behavior in non-humans

(Phys.org)—A pair of researchers has undertaken a study of the current status of investigation into the decorating behavior of non-human organisms. Graeme Ruxton, with the University of St. Andrews and Martin Stevens with the University of Exeter, both in the U.K. have together published a paper in Royal Society Biology Letters, describing their findings.

Human beings adorn themselves with all manner of decorations, from clothes, to jewelry to tattoos and piercings and a lot of research has been done to better understand why we do this, but other animals decorate themselves as well, as the researchers note, but very little research has been done to better understand their motivations. In this new effort, Ruxton and Stevens conducted a search of the literature to find studies that have been done on the topic and have used what they have found to offer some theories.

The researchers note that decorator crabs appear to have garnered the most attention from researchers—they have actually evolved in a way that helps, growing little hooks on their bodies for assistance with attaching bits of coral and other material. They note also that the consensus among prior researchers is that the crabs decorate themselves to ward off predators, but thus far it has not been proven—they suggest further research be undertaken to make a stronger case. They also note that some studies have been done regarding other aquatic species, such as with other types of crabs and sea urchins. There too it appears that the primary reason for decoration in most species is self preservation.

The researchers note that self decoration is not limited to sea creatures, though it is less prevalent with terrestrial species, presumably because it exerts more of a toll—carrying around ornamentation can be hard work when not living in the near weightlessness of the sea. Most often, they note, it occurs with the young, shortly after birth or hatching, when it can help offspring hide. More specifically, they note that it occurs with some types of larvae carrying shields of sorts, sometimes made of fecal matter and with nymphs of assassin bugs, which use the dead carcasses of victims as backpacks to cover themselves. They note also that some species of spider use sand as camouflage and some birds use coloration they add themselves for a similar purpose, and some large ungulates use mud.

The researchers summarize the results of their efforts by nothing that non-human decoration is quite diverse and not enough is known about why it occurs. They suggest more study be undertaken by others, to learn more.