Spoiled for choice: Number of signalers constrains mate choice based on acoustic signals

In many taxa, receivers use signals to detect and discriminate among mates. Signal detection and discrimination thus has important fitness consequences for individuals. Noise is defined as any factor that prevents detection or discrimination of signals. The noise produced by groups of signaling animals is a well-known impediment to signal detection and discrimination in animals, but how many signals produce the emergent, masking effects of noise? This dataset was generated to explore how receivers discriminate among signals in noisy, multi-choice environments. Subjects were female Australian field crickets, Teleogryllus oceanicus. We performed a series of phonotaxis (movement toward sound) assays in which we manipulated the number of long chirps in the signal. First, we assessed female preferences for the number of long chirp pulses and found that receivers preferred more long chirp pulses to fewer. Then we gave receivers a choice between a preferred, 7-pulse signal and either 1, 3, 5, or 7 presentations of the non-preferred, 2-pulse signal ("the multi-choice experiment"). We observed the probability that subjects left the release point, the probability that subjects responded to playback, and the probability of choosing the preferred stimulus. We also recorded the subject's latency to leave the release point and the latency to respond to playback. Because the angular separation between speakers decreased with increasing number of playback speakers in the multi-choice experiment, we then conducted an experiment ("the angular separation experiment") to determine whether observed effects were due to the spatial configuration of speakers or due to the emergent noise of multiple playback speakers.