Which statement about the great hornbill's casque is most accurate?

Which statement about the great hornbill's casque is most accurate?

• A. It stores water
• B. It is used to crush seeds
• C. Its exact function is not fully understood; may be used for display or fighting
• D. It helps in flight stability

Answer: (C)

The casque on a great hornbill is a conspicuous, hollow structure on top of the bill whose exact function isn’t yet settled. Researchers generally think it’s tied to social signaling—helping individuals display to mates or competitors—and it may also influence sound production, acting as a resonator. There isn’t solid evidence that the casque stores water, aids in crushing seeds, or helps with flight stability, so the most accurate current understanding is that its exact role isn’t fully known and it may be used for display or fighting.

The casque on a great hornbill is a conspicuous, hollow structure on top of the bill whose exact function isn’t yet settled. Researchers generally think it’s tied to social signaling—helping individuals display to mates or competitors—and it may also influence sound production, acting as a resonator. There isn’t solid evidence that the casque stores water, aids in crushing seeds, or helps with flight stability, so the most accurate current understanding is that its exact role isn’t fully known and it may be used for display or fighting.