Whales are regularly observed swimming through kelp forests, rubbing against the brown seaweed and wearing it on their heads like headgear. This behavior, known as "kelping" ("kelp" being a species of seaweed), was first observed in 2007. Although the exact reasons for this behavior are debated, hypotheses put forward include the regulation of parasites on their skin, relief from itching, and even play. A recent study from the University of Queensland, in Australia, have discovered that humpback whales worldwide enjoy the contact of seaweed on their skin as a form of play and potentially as a gentle body scrub.