Hornbills are a family (Bucerotidae) of more than fifty species of bird found in Africa and Asia. Hornbills originated in Africa, and are initially divided into ground-dwelling species (two species found only in Africa), and arboreal (tree-dwelling, the remainder), and subsequently into Asian and African species. 

The primary theory for the origins of hornbills, is that they evolved initially in Africa spreading into Asia when the Indian continental plate split from Africa around 55 million years ago, colliding around 10 million years later with Asia, forming the Himalayas, and carrying hornbills into Asia. One Asian species, Berenicornis comatus, the white-crowned hornbill, is more closely related to African hornbills than to the rest of the Asian hornbills, having therefore split earlier, whereas other Asian species share subsequent Asian common ancestors.

The hornbills have long bills, which they use for feeding on fruit and insects (different species vary in diet between exclusively insect-eating, fruit-eating, or both). They swallow food by tilting their head back, as their tongues are too short for this job.