Measurement and control of vocal interactions in songbirds
One obstacle for investigating vocal interactions in vertebrate animals is difficulty of discriminating individual vocalizations of rapidly moving, sometimes simultaneously vocalizing individuals. To overcome this obstacle, we have developed an ultra-miniature back-attached sound/acceleration recording system that allows perfect separation of birdsong vocalizations irrespective of background noise and the number of vocalizing animals nearby. With this system, we have been able to identify hierarchies in the vocal interactions among adult male and female zebra finches. Furthermore, to causally interfere with vocal interactions in groups of up to four birds, we have developed an echo cancelation system that allows us to have full digital control of vocal interactions between any bird pair. With these tools, we hope to be able to further advance the dissection of vocal communication in songbirds.