It’s a sonic phenomenon that occurs in only certain pockets of desert around the world. The sound of sand grains shuffling down hot slopes that can recall the angry buzz of bees or the deep, groaning thrums of a didgeridoo group. Scientists refer to these shifting dunes as “singing” or “booming” sands, which for centuries mystified explorers from Charles Darwin to Marco Polo. We know now that these strange sounds are caused by the vibrations of grains avalanching, at relatively slow speeds, down dunes, and that the grain size and speed influence the notes of these curious hums of nature.
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