Jacob Rees-Mogg and Rab C. Nesbitt excepted, it has become quite difficult to infer much from people’s appearance. In these democratically dressed and coiffed times, we usually have to wait until people start to speak before we get a bead on them. Voice has become the best, and often only, signifier we can rely on. A flat vowel here, a glottal stop there, a hint of sibilance about an ‘s’ — ahah: northern, possibly Yorkshire, probably lower-middle-class-ish background and, going by the ‘s’, gay.
We make such judgments with great confidence. And, it transpires, little justification — it’s the great insight of this study of human conversation that our voice-interpreting skills, on which we often set much store, are actually pretty poor.