Fig. 2From: Previously unknown behavior in parasitic cuckoo females: male-like vocalization during migratory activitySpectrograms of male-like a–c and atypical d–g vocalizations. The figure shows vocalization of a female F1 Oriental Cuckoo, b female F2 Oriental Cuckoo, c female F3 Oriental Cuckoo, d “unknown cuckoo” from South Korea, e “Common × Oriental Cuckoo hybrid” from Primorski Krai (Russia), as well as f two atypical calls recorded in Taiwan (China) and g atypical call recorded in Hebei Province (China). For A-notes (i.e. notes of both male-like and atypical calls), the numbers highlight position of note in the call (e.g. A2 means the second A-note). Variants of male-like and atypical calls: A1, single-note calls, A1–A2, two-note calls, and A1–A2–A3, three-note call. B, Kuk-call; INT, introductory call. Calls separated by dotted lines are from the same individual; all others are from different individualsBack to article page