..An analysis of social behaviors and call usage in mustached bats can be useful in addressing the evolutionary expansion of audiovocal communication in the specialized selleck Volasertib ecological niche of this species. Additionally, because of the discrete nature of mustached bat vocalizations, this analysis also provides an excellent opportunity to examine whether the acoustic signal structure in bat calls conforms to the rules of the Motivation-Structure hypothesis that is presumed to be widely applicable to avian and mammalian vocalizations [24, 30, 31]. Therefore, our objective was to investigate patterns of roosting positions and the behavioral context and social function of a variety of call types produced by the mustached bat, Pteronotus parnellii.2. Methods2.1. Animal MaintenanceFifteen adult mustached bats, P.

parnellii, were collected from a cave near Chaguanas, Trinidad, in September 2002. The ten males and five females were housed at Georgetown University and maintained at 28�� to 30��C and 60% to 70% humidity under Biosafety Level II conditions with a 6:18 hour light-dark cycle. The colony was kept in a 4.0m �� 2.5m �� 2.5m flight room where they could fly at will and roost in two upside-down pots fixed on the ceiling. The inside surface of the pots was coated with a 1:1 cement and Plaster-of-Paris mixture to provide a rough surface for roosting. The bats were provided mealworms and vitamin fortified water ad libitum.2.2. Audio-Video RecordingsTo establish associations between P.

parnellii social calls and other behaviors, we made audio-video recordings of the bats with a Sony TRV310 digital HI8 video camera with an attached Optimus unidirectional condenser microphone (flat, within a 5dB range; sampling rate of 44kHz). We used a Lorex VQ-2120 infrared light so that we could record in the absence of visible light. We supplemented this with simultaneous ultrasonic recordings made with a bat detector (model U30; Ultrasound Advice), band-pass-filtered (between 4 and 100kHz; model 3550; Krohn-Hite), digitized with a PCMCIA card (DAS16/330; Computer Boards, Inc.) at a sampling rate of 250kHz for the broadband spectrum (flat with 5dB up to 100kHz), and recorded to a personal computer (Inspiron 7500; Dell Computers). A RACAL ST0705 tape recorder (set to 30in/s) was also used to obtain high-resolution recordings of mustached bat calls for a general analysis of call structure.

To reduce excess noise before recording, sound frequencies below 5kHz and above 100kHz were filtered out using a Krohn-Hite filter (model 3550) with a 24-dB/octave Batimastat slope. A 20dB Hewlett Packard 465A amplifier was used to magnify the oscilloscope trace and audibility of the band-passed frequencies. A two-channel Tektronix 2211 digital storage oscilloscope was used to compare the quality of the original and the recorded sounds.