Notches in the wings of male fork-tailed flycatchers may broadcast their availability to mates
Juan Jose Arango / VWPics / Alam
As male fork-tailed flycatchers zip around, their wings can produce a high-pitched trilling. New research shows these whistles have dialects and may be used for communication.
Fork-tailed flycatchers (Tyrannus savana) have two subspecies: one that migrates annually between northern and southern parts of South America and another that resides year-round in the north of the continent. Valentina Gómez-Bahamón at the Field Museum in Illinois and her colleagues studied the two populations.
They collected and analysed audio and …