Hornbills are large, colorful birds found mainly in tropical and subtropical forests of Africa, Asia, and the Indian subcontinent. They are known for their distinctive long bills, which can be quite large and often have a casque on top. There are about 60 species of hornbills, and they play an important role in their ecosystems by dispersing seeds. These birds are social and often live in small groups or pairs. Hornbills are also unique in their nesting behavior; the female seals herself inside a tree cavity during breeding, leaving only a small opening for the male to feed her and the chicks.