The start of spring holds a characteristic outdoors odor. It’s a bit of dirt, mixed in with sharp greenness and an unmistakable whiff of ozone. Its called Geosmin and our noses are so finely tuned to this organic compound, in fact, that according to Popular Mechanics we can detect it better than sharks can recognize blood.
Buuuuuut as it finally turns out, the source of this smell, its er not so romantic.
For the very first time, excited scientists at the Swedish University of Agricultural Sciences, the John Innes Centre, and Lund University have identified why this distinct scent has persisted: a mutually-beneficial relationship between a six-legged worm, known as the springtail, and Streptomyces, a type of bacteria commonly found in soil.
Springtails are attracted to the smell of geosmin associated with the bacteria which basically then hitches a ride on Springtails that spread their tiny spores.
-Ed
Detailed source here – https://www.popularmechanics.com/science/environment/a32065673/spring-smell-geosmin-soil-springtails/
