title: Koalas use a novel vocal organ to produce unusually low-pitched mating calls.
abstract: During the breeding season, male koalas produce 'bellow' vocalisations that are characterised by a continuous series of inhalation and exhalation sections, and an extremely low fundamental frequency (the main acoustic correlate of perceived pitch) [1]. Remarkably, the fundamental frequency (F0) of bellow inhalation sections averages 27.1 Hz (range: 9.8-61.5 Hz [1]), which is 20 times lower than would be expected for an animal weighing 8 kg [2] and more typical of an animal the size of an elephant (Supplemental figure S1A). Here, we demonstrate that koalas use a novel vocal organ to produce their unusually low-pitched mating calls.
authors.affiliation: School of Psychology, University of Sussex, Brighton, BN1 9QH, U.K. Electronic address: b.d.charlton@sussex.ac.uk.
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Charlton
authors.forename: Roland
authors.initials: R
authors.lastname: Frey
authors.forename: Allan J
authors.initials: AJ
authors.lastname: McKinnon
authors.forename: Guido
authors.initials: G
authors.lastname: Fritsch
authors.forename: W Tecumseh
authors.initials: WT
authors.lastname: Fitch
authors.forename: David
authors.initials: D
authors.lastname: Reby
mesh_terms: D000818:Animals; D001239:Inhalation / Q000502:physiology; D007830:Larynx / Q000033:anatomy & histology* / Q000502:physiology; D008297:Male; D048368:Phascolarctidae / Q000502:physiology*; D012726:Sexual Behavior, Animal; D014828:Vocalization, Animal / Q000502:physiology*