Interestingly, even the sound of the word ‘round’ feels gentle, while the word ‘spiky’ has high-frequency peaks (at p and k)! I wonder if dogs (or for that matter, humans) can accurately zero-shot classify words that represent round vs spiky for different languages.

It appears to me that onomatopoeia, at varying degrees, played a role in the spontaneous convergence of verbal communication, and thus the development of a language.

When I studied psychology 20 years ago we had a class which covered this, and at least then there were studies indeed showing these associations are exactly due to these phonetic identifiers.