Solomon Island skinks are also commonly known as monkey-tailed skinks, or prehensile-tailed skinks, for their unique prehensile tail. This tail acts like a fifth limb when the skinks are clambering about in the trees. If a skink slips from a branch, it can hold its entire body weight by its tail. Solomon Island skinks are also known for living in family groups called a circulus, which are unusual among reptiles. Both male and female skinks will defend the territory, and members, of a circulus, even if they are not directly related.