COVER STORY: SPECIES PROFILE
HORNBILLS range on size from the dove-sized red-billed dwarf horribill (Lophoceros camurus) to the two species of turkey-sized ground hornbills (Bucorvus). The 61 species of hornbills occupy two families. The Bucorvidae comprises the two mighty species of ground hornbills from Africa, while the 59 species in the Bucerotidae include the charismatic great hornbill (Buceros bicornis), also called the great pied or great Indian hornbill, which is the largest of the family.
Their closest relatives are believed to be woodhoopoes and hoopoes, yet hornbills have a number of unique anatomical features that justify assignment to their own order.
The large beak and casque instantly identify a hornbill. Beak and casque grow at different rates and even in the rhinoceros hornbill , where the casque is almost as long as the beak (hencehornbill's wings produce a recognisable “woodwind” whooshing sound as it flies overhead. All male hornbills are larger than females, though with a smaller beak and casque. The male great hornbill has red eyes whereas the female's are white, and her orbital skin reddens in breeding condition. Unlike the male, she lacks black markings on her casque.
