Overview

• A peer-reviewed Nature Ecology & Evolution paper reports 21 bird species across four continents use a near-identical “whining” call to flag brood parasites.
• Field experiments show hosts give the call to taxidermied cuckoos and seldom to predators, then rapidly mob the perceived parasite.
• Playback trials demonstrate cross-species and cross-regional recognition, with birds in Australia and China responding similarly to each other’s calls.
• Comparative analyses link the call’s presence to areas with dense host–parasite networks, consistent with a role in coordinating interspecific defense.
• The authors conclude the signal combines learned production with an innate response, illustrating how learned meanings can attach to innate sounds in line with long-standing evolutionary ideas.