Source: Netherlands Institute of Ecology (NIOO-KNAW)
Leaf-feeding caterpillars greatly enrich their intestinal flora by eating soil. It's even possible to trace the legacy effects of plants that previously grew in that soil through bacteria and fungi in the caterpillars. Plant legacy affects above ground insects through soil
Earlier research had found that below-ground and above-ground insects can communicate with each other using plants as a kind of 'green telephone'.
Messages can even be left in the soil to be retrieved later, like voicemail.
This new research by a team of four ecologists shows that surprisingly, above-ground insects such as caterpillars can retrieve these voicemails from the soil without any mediation from plants.
So do caterpillars really play doctor? The researchers confirm that they may be actively searching the soil for beneficial substances and micro-organisms: "you could think of it as self-medicating."
Among the things they observed during their experiments was an abundance of soil bacteria that are known to have a symbiotic relationship with the intestines of insects and even humans.