Insects Invented Farming Long Before Humans Did
Fossilized termite nests in Africa reveal the insects to have been the world's oldest farmers, practicing a type of cultivation millions of years before humans came onto the scene.
The finding comes from a team led by Eric Roberts of James Cook University, working on a site in the Great Rift Valley of Tanzania. That section of the valley, known as the Rukwa Rift Basin, was home to ancient termite colonies that have since been preserved in fossilized form. The fossilized termite nests were found amid sediments dating back to 25 million years ago.
In an email to The Washington Post about the Rukwa Rift discovery, Roberts wrote: "It captures a record of the evolutionary coupling of termites and fungus ... and allows us to trace back the antiquity of this symbiotic relationship."
Modern African rainforest termites are known for their fungi farming activities. They cultivate "gardens" of African Termitomyces mushrooms within huge earth chambers full of thousands of workers and soldiers. The termites' farming activities facilitate the conversion of the fungi into a food source that is more easily digestible to their insect population.
Roberts noted that scientists have taken DNA from such modern termites and used it to estimate the origins of the farming behavior, dating it to at least 25 to 30 million years ago. The Rukwa Rift discovery further substantiates the earlier research.
Duur Aanen from Wageningen University, a co-author of Roberts on the study, said that the emergence of farming behavior in termites had wide-ranging effects on the ecology of prehistoric Africa. Just as agriculture allowed our human ancestors to establish themselves in a wider variety of habitats, so did fungus farming aid termites in their ability to range outside of the rainforest. Termites became able to build colonies in the savannah and other environments, eventually leading them to migrate to Asia.