Scientists find horses produce two sounds at once - a deep vocal tone and a high whistle - revealing how their complex whinny ...

They found that a single whinny can include simultaneous low and high sounds, suggesting that horses have a richer spectrum of calls than other mammals. The low sounds in horse whinnies are at a ...

The whinny is an unusual combination of both high and low pitched sounds, like a cross between a grunt and a squeal - that come out at the same time.