This headline feels slightly misleading to me. As far as I can tell, this research shows that sperm whale clicks have spectral properties which are analogous in

This headline feels slightly misleading to me. As far as I can tell, this research shows that sperm whale clicks have spectral properties which are analogous in some ways to human vowels. In particular, they exhibit formants (essentially, amplified frequency bands), and analysing them reveals that these whales produce two different kinds of clicks. While fascinating in their own right, I feel it isn’t entirely fair to call these ‘vowels and diphthongs’ without qualification: these seem to admit a lot less variation than do human vowels.