Chimpanzee voice prints? Insights from transfer learning experiments from human voices
This work addresses the challenge of individual vocal identification in non-human animals, particularly chimpanzees, using transfer learning from human data, which is incremental but offers practical benefits for small datasets.
The study tackled the problem of identifying unique voice prints in chimpanzees by leveraging a deep neural network feature extractor pre-trained on over 10,000 human voice prints, achieving improved results compared to traditional acoustic features.
Individual vocal differences are ubiquitous in the animal kingdom. In humans, these differences pervade the entire vocal repertoire and constitute a "voice print". Apes, our closest-living relatives, possess individual signatures within specific call types, but the potential for a unique voice print has been little investigated. This is partially attributed to the limitations associated with extracting meaningful features from small data sets. Advances in machine learning have highlighted an alternative to traditional acoustic features, namely pre-trained learnt extractors. Here, we present an approach building on these developments: leveraging a feature extractor based on a deep neural network trained on over 10,000 human voice prints to provide an informative space over which we identify chimpanzee voice prints. We compare our results with those obtained by using traditional acoustic features and discuss the benefits of our methodology and the significance of our findings for the identification of "voice prints" in non-human animals.