Small gregarious, long-tailed, mainly grey or brown birds endemic to Africa. They have crests and stubby bills. Unusual leg structure (strong claws and reversible outer toes (pamprodactyl feet)) means they usually hang from branches rather than perching upright.
They are arboreal and scurry through the leaves like rodents, in search of berries, fruit and buds. They are acrobatic, and can feed upside down. They regularly sunbathe with the legs apart and the short belly-feathers raised to expose the belly skin. They also dustbathe.
They are monogamous or polygamous abnd they often breed communally. The nest is a small bowl lined with plant down. They lay 2 - 4 white or lightly scrolled eggs. Incubation and care of young is done by both sexes.

Colius = sheath, in reference to the long tail
Urocolius = tail sheath

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