The development of agriculture is widely seen as one of the pivotal moments in the development of modern human civilization, yet new research shows that humans were a rather late addition to the agriculture world. A recently published article in Nature Communications claims that South American Attini ants developed large-scale agriculture between 50 and 60 million years before humans did, changing ant evolution in the process.
According to this new research, ant agriculture is conducted on a scale comparable to that of modern humans:
The Attini ant–fungus agricultural symbiosis evolved over tens of millions of years, producing complex societies with industrial-scale farming analogous to that of humans. […] In contrast to human farming, increasing dependence on a single cultivar lineage appears to have been essential to the origin of industrial-scale ant agriculture.
Ant agriculture began around 50 to 60 million years ago when this particular Attini tribe of South American ants began cultivating fungus inside their subterranean colonies. The ants feed fresh leaf matter to the fungus, providing ant colonies with a renewable food source. While it has been previously observed that some ants exist in a symbiotic state with fungus colonies, this research is the first to trace the ancient development of ant agriculture to such an early timeline.
Researchers came to this conclusion after sequencing the entire ant genome in order to ascertain when certain genomic changes occurred, and discovered that 25 million years ago, ants lost the ability to synthesize certain amino acids that were once required due to their pre-agricultural diet. According to Jacobus Boomsma, biologist at the University of Copenhagen and co-author of this research, these dietary changes brought about permanent, irreversible changes to the ant genome:
The ants lost many genes when they committed to farming fungi. It led to an evolutionary cascade of changes, unmatched by any other animal lineage studied so far.
This research is part of a larger study of ant populations intended to trace the development of the ant-fungus symbiosis found in many parts of the world. The discovery of wide-scale agriculture at such an early stage in Earth’s history is surprising given how much later humans, supposedly the most intelligent living organisms on the planet, developed it.