“…pika, Ochotona princeps: Conner, 1985; tree shrew, Tupaia belangeri: Binz & Zimmermann, 1989; ringtailed lemur, Lemur catta: Macedonia, 1993 Leuchtenberger, Sousa-Lima, Duplaix, Magnusson, & Mourão, 2014), few mammalian studies directly address the potential function and subsequent adaptive benefit of low-amplitude calls. In comparison, a growing body of research on low-amplitude vocalizations in birds reveals that low-amplitude calling plays an important role in warning conspecifics of predator threats (Dabelsteen, McGregor, Lampe, Langmore, & Holland, 1998) and in mediating a multitude of social contexts, such as competitive interactions (Akçay, Tom, Holmes, Campbell, & Beecher, 2011;Searcy & Nowicki, 2006), courtship (Dabelsteen et al, 1998;Reichard, Rice, Vanderbilt, & Ketterson, 2011;Reichard, Rice, Schultz, & Schrock, 2013) and pair bond maintenance (Elie et al, 2010).…”