Editing Hummingbird (section)

=== Wing feather trill ===

Male rufous and broad-tailed hummingbirds (genus ''[[Selasphorus]]'') have a distinctive wing feature during normal flight that sounds like jingling or a buzzing shrill whistle {{ndash}} a trill.<ref name="miller">{{Cite journal  |last1=Miller |first1=Sarah J. |last2=Inouye |first2=David W. |date=1983 |title=Roles of the Wing Whistle in the Territorial Behaviour of Male Broad-tailed Hummingbirds (''Selasphorus platycercus'') |url=http://www.hummingbirds.net/miller1983.html |journal=Animal Behaviour |volume=31 |issue=3 |pages=689–700 |doi=10.1016/S0003-3472(83)80224-3 |access-date=13 July 2014 |via=hummingbirds.net |s2cid=53160649}}</ref> The trill arises from air rushing through slots created by the tapered tips of the ninth and tenth primary wing feathers, creating a sound loud enough to be detected by female or competitive male hummingbirds and researchers up to 100&nbsp;m away.<ref name="miller"/>

Behaviorally, the trill serves several purposes: It announces the sex and presence of a male bird; it provides audible aggressive defense of a feeding territory and an intrusion tactic; it enhances communication of a threat; and it favors mate attraction and courtship.<ref name="miller"/>