Vowels and Diphthongs in Sperm Whales

Abstract

Sperm whale vocalizations are among the most intriguing communication systems in the animal kingdom. Traditionally, sperm whale codas, or groups of clicks, have been primarily analyzed in terms of the number of clicks and their inter-click timing. This paper argues that acoustic properties of clicks in codas are likely meaningful and actively controlled by whales. We present a visualization technique that allows us to describe several previously unobserved patterns. We argue that sperm whale codas are on many levels analogous to human vowels and diphthongs: vowel duration and pitch correspond to the number of clicks and their timing (traditional coda types), while spectral properties of clicks correspond to formants in human vowels. We identify two recurrent patterns that appear across individual sperm whales: the a-coda vowel and i-coda vowel. Both coda vowels are possible of different traditional coda types. Our discovery thus suggests that codas are highly compositional. We also show that sperm whales have diphthongal patterns on individual codas: rising, falling, rising-falling and falling-rising formant patterns are observed. Finally, we control for whale movement and present several pieces of evidence suggesting that the observed patterns are not artifacts, but are actively controlled by sperm whales. We also show that the two coda vowels (the a-vowel and i-vowel) are actively exchanged by sperm whales in dialogues. The uncovered spectral properties suggest that codas are highly compositional, more informative, and more complex than previously thought.

WITHDRAWN: Elephant rumble vocalizations: spectral substructures and superstructures

“…An increasing list of studies are showcasing the ability of various species to modify their vocal tracts [15,[31][32][33][34][35][36][37][38][39][40][41][42][43]. In the case of some primates in particular, vocal tract manipulation has been shown to include articulatory movements such as changes in position of the lips, the larynx, and the jaw [33,35,39,40,42].…”

“…vocal tract resonance frequencies) manipulation and phonetically contrasting sounds, akin to human vowels. Indeed, the presence of vowels or vowel-like spectral structures is explicitly mentioned in several primate and non-primate studies [34,37,[39][40][41][42][43][44][45].…”

“…However, as our study will demonstrate, rumbles exhibit spectral substructures and variations. Investigating these substructures within rumbles is crucial for identifying the basic acoustic units in elephant vocalizations -akin to whale clicks [43,[46][47][48][49] or human phonemes [50][51][52] -and for exploring their potential functionality or their associated semantic information.…”

The Ethics of Using Artificial Intelligence in Scientific Research: New Guidance Needed for a New Tool

“…Although we do not know of any cases where scientists have been charged with research misconduct for presenting synthetic data as real data, it is only a matter of time until this happens, given the pressures to produce results, publish, and obtain grants, and the temptations to cheat or cut corners. 21 This speculation is further corroborated by the fact that a small proportion of scientists deliberately fabricate or falsify data at some point in their careers [74,142]. Also, using synthetic data in research, even appropriately, may blur the line between real and fake data and undermine data integrity.…”

“…• Analyzing data and images [35,44,66,90,108,117,124,126,151,163]. • Interpreting data and images [13,14,21,42]. • Generating hypotheses [33,38,42,109,151].…”