Scientists hid speakers along a third of a mile of hiking trail in Boulder, Colorado, to fake a richer birdsong chorus, and hikers who never spotted them still walked away calmer

Scientists hid speakers along a third of a mile of hiking trail in Boulder, Colorado, to fake a richer birdsong chorus, and hikers who never spotted them still walked away calmer

Between July and September 2017, a team from California Polytechnic State University buried speakers along roughly a third of a mile stretches of trail in the Boulder Open Space and Mountain Parks system, wired them to play recordings of birdsong, and waited to see whether hikers who walked past could tell the difference. Most, by the researchers’ own account, could not. The study, published in Proceedings of the Royal Society B in December 2020…