Acoustic Pattern Learning in Birds and Humans (#201)
The bioacoustics of animal vocalizations can give us surprising insights into acoustic pattern learning abilities across species. This can be especially useful when looking for human-like acoustic abilities in other species. Human speech signals can give us insight into what kinds of features are important in human language perception. In one study, the perception of metrical patterns in human speech were evaluated in humans and budgerigars. First, we looked at previous research studying the structure of metrical patterns in humans speech. We used this information to create two syllable nonsense words where either the first or the second syllable was emphasized, and we trained both species to discriminate the two patterns of emphasis. We found that both humans and budgerigars were able to detect metrical phonology in these signals, suggesting that detecting these kinds of patterns may be a general acoustic perceptual ability, at least in vocal learning animals. In another study, we evaluated relative pitch perception in the black-capped chickadee. Relative pitch is the ability to identify the ratio difference between two notes, a common perceptual phenomenon in humans that is used frequently in music to create tension and release. While many avian species appear to have trouble with relative pitch, looking at the bioacoustics of black-capped chickadee song and previous perceptual research, we knew that relative pitch was readily produced and perceived by this species in the performance and evaluation of their species-specific song. We found that the relative pitch ratios used in natural songs are processed more readily than other arbitrary relative pitch relationships. In conclusion, by evaluating the natural vocalizations of species we gain insight in possible perceptual abilities that then can be tested in laboratory studies, leading to value insights on comparative perception.