No need to shout: Effect of signal loudness on sibling communication in barn owls Tyto alba

摘要: In animal communication, signal loudness is often ignored and seldom measured. We used a playback experiment to examine the role of vocal (i.e., sound pressure level) in sibling communication nestling barn owls Tyto alba. this species, siblings vocally negotiate among each other for priority access parental food resources. Call rate call duration play key roles system, with most nestlings deterring their from competing item next delivered by parents. Here, we broadcast calls at different levels live nestlings. The did not affect owlets' investment rate, or loudness. which were affected but influence response terms This suggests that selection producing loud signals may be weak as attract predators. Moreover, given owlets do overlap they communicate nearby silence night, necessary convey reliable information about need.