The team discovered that male and female baboons each produce four vowel-like sounds. Females produce one that males don’t, and vice versa, so in total there are five distinct vowels. They correspond to the second syllable in “roses”, and the vowel sounds in “you”, “thought”, “trap” and “ah” (PLoS One, DOI: 10.1371/journal.pone.0169321).
The findings raise fresh doubts about the link between the position of the human larynx and the origin of speech, says Fagot. He thinks important features of spoken language may have originated as far back as the common ancestor of monkeys and humans, which lived about 25 million years ago.
One way to read this slowly unfolding thought (in my recent posts) about non-human intelligence is that evolution is slower than we can imagine. Yes, we became precisely human when our species popped up, but imprecise versions of human are still pretty close.