1,000 Swiss volunteers buried their underwear for science — and mapped the hidden life in the soil

It began as a delightfully odd request: please bury your cotton underwear. As part of the citizen-science project 'Proof by Underpants,' 1,000 volunteers across Switzerland buried more than 2,000 pairs of cotton underwear and 12,000 tea bags at about 1,000 sites, then dug them up two months later and photographed the remains. Researchers from the University of Zurich and Agroscope, publishing in the journal Plants, People, Planet, turned the evidence into a map of biological activity in Swiss soils: the more alive the soil, the faster the cotton vanished. Private gardens teemed fastest; lawns were slowest. A playful experiment, with a serious gift — a simple 'underwear index' anyone can use to check the health of the ground beneath their feet.

SDG 15 · Life on land