Atmospheric formic acid from formicine ants.

Formic acid is a ubiquitous constituent of the atmospheric gas and of precipitation, but its sources and their fluxes are poorly understood. One source not previously examined, emissions from formicine ants, is assessed in this work, and it is shown that, except in urban areas and particularly in tropical areas, the ants may be a significant source of the formic acid found in the atmosphere. This discovery provides a new example of the strong interactions linking the biosphere and the atmosphere.