title: Male discrimination of receptive and unreceptive female calls by temporal features.
abstract: In murky, crowded ponds in South Africa, female clawed frogs, Xenopus laevis (Daudin), vocalize to signal reproductive state. Female calls consist of acoustically similar clicks delivered in trains with characteristic rates. The rapping call of a sexually receptive female has a more rapid click rate [81 ms mean interclick interval (ICI)] than the ticking call of an unreceptive female (219 ms ICI). Rapping stimulates male advertisement calling, whereas ticking suppresses an already calling male. We examined how males label and discriminate female click rates. A labeling boundary experiment revealed that males perceive click rates between the means of rapping and ticking as lying on a continuum. They respond to 98 and 160 ms ICI as though to rapping and ticking, respectively. However, calling evoked by a click rate equally common to both calls (120 ms ICI) did not differ from the response to either rapping or ticking. A second experiment evaluated whether males discriminate click rates both labeled as ticking (180 and 219 ms ICI). Ticking suppresses advertising males, and suppressed males habituate (resume calling) to prolonged ticking. Both ticking stimuli suppressed males with equal effectiveness, and males habituated in equivalent amounts of time. When the stimulus was switched during habituation, no dishabituation occurred. We conclude that male labeling of click trains as rapping or ticking reflects an ambiguity resulting from the overlap in ICIs naturally occurring in the calls. Males do not respond differentially to click rates within the ticking category. Males thus combine discriminating and non-discriminating strategies in responding to the salient feature of female calls.
authors: Neurobiology and Behavior, Columbia University, New York, NY, USA. taffeta@berkeley.edu
authors: Taffeta M
authors: TM
authors: Elliott
authors: Darcy B
authors: DB
authors: Kelley
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D011898:Ranidae / Q000502:physiology*; D012726:Sexual Behavior, Animal / Q000502:physiology*; D014828:Vocalization, Animal / Q000502:physiology*
references: J Exp Psychol. 1957 Nov;54(5):358-68
references: 13481283
references: Percept Psychophys. 1993 Nov;54(5):567-78
references: 8290326
references: Science. 1978 Mar 10;199(4333):1089-91
references: 628833
references: J Neurosci. 1987 Oct;7(10):3191-7
references: 3668623
references: Proc Biol Sci. 2007 Feb 22;274(1609):479-88
references: 17476767
references: Horm Behav. 1983 Dec;17(4):388-404
references: 6662518
references: J Exp Psychol Hum Percept Perform. 1990 Nov;16(4):728-41
references: 2148588
references: Science. 1989 May 26;244(4907):976-8
references: 2727689
references: Science. 1996 Sep 13;273(5281):1542-4
references: 8703214
references: Anim Behav. 2004 Feb 1;67(2):353-365
references: 23457414
references: Proc Natl Acad Sci U S A. 1998 Feb 17;95(4):1870-5
references: 9465109
references: J Exp Psychol. 1961 May;61:379-88
references: 13761868