Full Description

"We chose sneaker (type II) males since they attempt to steal fertilizations from territorial type I males who use an advertisement call (hum) to attract females yet are also subjected to vocal agonistic behavior (grunts) by type I males."

"There are two distinct male sexual phenotypes with corresponding alternative reproductive tactics: type I males are the aggressive, territorial morph which court females into their nests by emitting multiharmonic advertisement calls or “hums”, while type II males sneakspawn in competition with larger type Is. Importantly, type II males are also the recipient of physical and vocal agonistic behavior (e.g., grunts) by type I males (Brantley and Bass, 1994)."

"All three reproductive morphs (type I, type II, female) are capable of producing short-duration broadband agonistic “grunts” which are sonically distinct from hums (Bass and McKibben, 2003; Brantley and Bass, 1994; McKibben and Bass, 1998). However, type I males are known to exclusively produce “grunt trains”, being defined as a rapid succession of single grunts at intervals of about 400 ms (Bass et al., 1999)."

"Reproductive type I males often produce trains of broadband, short-duration (50–200 ms) grunts to obviate potential nest interlopers (Brantley and Bass, 1994). Grunt trains have a repetition rate of about 2.5 Hz with grunt intervals of approximately 400 ms (Bass et al., 1999). In contrast, the hum is a long duration, multiharmonic signal with a fundamental frequency that ranges from 80 to 102 Hz (Bass et al., 1999). The several prominent harmonics contained within the hum range up to 400 Hz with additional lower amplitude harmonics at ≥800 Hz (Bass et al., 1999)."

"Hum-exposed males were subjected to a looped 30-minute playback of five field-recorded type I male advertisement calls (Fig. 1A). The audio files were equalized to the same maximum peak-to-peak sound level in MATLAB to account for any differences in amplitude between individual type I male callers. The average duration of hums (n = 5) contained in the looped playback was 7.8 ( ± 5.4 s.d.) min with a range of 2.2–13.6 min. Grunt-exposed type II males were subjected to a looped 30-minute playback of conspecific grunts (Fig. 1B). The average duration of n = 19 grunts sampled from the recording was 78.7 ( ± 9.3 s.d.) ms with a range of 67–97 ms."

Observation Environment Quotes

"Fig. 1. Visualization of the three acoustic treatments used in this study. Representative power spectra (red) and waveform insets (blue) from field-recorded hums (A), grunts (B), and a recording of ambient background noise that was made by placing a hydrophone in the center of the testing cage (C)."

"Hum-exposed males were subjected to a looped 30-minute playback of five field-recorded type I male advertisement calls (Fig. 1A). The audio files were equalized to the same maximum peak-to-peak sound level in MATLAB to account for any differences in amplitude between individual type I male callers. The average duration of hums (n = 5) contained in the looped playback was 7.8 ( ± 5.4 s.d.) min with a range of 2.2–13.6 min. Grunt-exposed type II males were subjected to a looped 30-minute playback of conspecific grunts (Fig. 1B). The average duration of n = 19 grunts sampled from the recording was 78.7 ( ± 9.3 s.d.) ms with a range of 67–97 ms."

Behaviour Description Quotes

"We chose sneaker (type II) males since they attempt to steal fertilizations from territorial type I males who use an advertisement call (hum) to attract females yet are also subjected to vocal agonistic behavior (grunts) by type I males. "

"There are two distinct male sexual phenotypes with corresponding alternative reproductive tactics: type I males are the aggressive, territorial morph which court females into their nests by emitting multiharmonic advertisement calls or “hums”, while type II males sneakspawn in competition with larger type Is. Importantly, type II males are also the recipient of physical and vocal agonistic behavior (e.g., grunts) by type I males (Brantley and Bass, 1994)."

Sound Name Quotes

"We chose sneaker (type II) males since they attempt to steal fertilizations from territorial type I males who use an advertisement call (hum) to attract females yet are also subjected to vocal agonistic behavior (grunts) by type I males. "

"Reproductive type I males often produce trains of broadband, short-duration (50–200 ms) grunts to obviate potential nest interlopers (Brantley and Bass, 1994). Grunt trains have a repetition rate of about 2.5 Hz with grunt intervals of approximately 400 ms (Bass et al., 1999). In contrast, the hum is a long duration, multiharmonic signal with a fundamental frequency that ranges from 80 to 102 Hz (Bass et al., 1999). The several prominent harmonics contained within the hum range up to 400 Hz with additional lower amplitude harmonics at ≥800 Hz (Bass et al., 1999)."