Chimpanzee voice prints? Insights from transfer learning experiments from human voices

TL;DR

This study explores whether transfer learning from human voice data can identify individual chimpanzee voice prints, demonstrating a novel approach that surpasses traditional acoustic features in accuracy.

Contribution

The paper introduces a transfer learning method using a deep neural network trained on human voices to detect chimpanzee voice prints, a novel application in animal vocalization analysis.

Findings

Transfer learning improves chimpanzee voice print identification.

Deep neural network features outperform traditional acoustic features.

Method offers new insights into non-human animal vocal individuality.

Abstract

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.