How Ants Became the World’s Best Fungus Farmers | Science | Smithsonian
The leafcutter ants, or attine ants, include the genus Atta and they eat a significant fungi form a true symbiosis, with both partners benefiting from the relationship. bacteria from growing on the rotting leaves in competition with the fungus. Leaf-cutter ants are a paradigmatic example, cultivating their mutualistic in wood through their association with both eukaryotic and bacterial .. The mutualism between leaf-cutter ants and their fungal cultivar has been. Ingenious leafcutter ants have developed a successful symbiotic relationship with the fungi they farm. New genetic analysis helps pinpoint.
These wee agricultural wizards used sophisticated techniques that rival our own—including domesticaing crops that today are unknown in nature and are also unable to survive without their cultivators. These diminutive farmers are united by a common strategy: They forage for bits of vegetation, but don't eat it. Instead, they use it to nourish their precious fungi, which they grow on an industrial scale. In these cases, fungi are completely isolated in underground gardens, often located in dry, inhospitable habitats where their wild relatives can't survive.
As a result of this isolation, the domesticated fungi have evolved in complete codependency with their ant farmers.
Leafcutter ants, fungi, and bacteria
We cultivate things that are so highly modified that they exist in forms no longer found in the wild. Recent work studying the DNA of both the ants and the fungi has shown that different colonies of the same ant often grow different species of fungi, despite the fact that each individual colony only farms a single species of fungus.
There is also some evidence that ants occasionally "steal" a fungus from a neighboring colony. Although most of the fungi grown by the attine ants are unique to the ant colonies, there are two exceptions: This suggests that the fungi were collected by the ants recently.
In one case in Florida a species of ant which was introduced in the s now grows a local Florida fungus in its nest. Presumably the original South American fungus that the ant arrived with died out in Florida, so the ant was forced to find a local replacement.
Fungal-Fungal Interactions in Leaf-Cutting Ant Agriculture
In this way the ants can adapt to a change in their environment. Though external factors play a large role in maintaining fidelity between the mutualists, genetic evidence of vertical transmission of partner fidelity has been found among asexual, fungus cultivating ant species.
The species Cyatta abscondita is considered the most recent ancestor of all leaf-cutting ants. They fall roughly into three major groups, only G1 having evolved gongylidia. Some G2 species grow long hyphae that form a protective cover over the nest. Those in G3 are paraphyleticthe most heteregenous, and form the most loose relationships with their cultivators. The fungi were earlier thought to be propagated by ants purely through clonal vegetative means. However considerable genetic variation in the fungi suggests that this may not be the case.
- How Ants Became the World’s Best Fungus Farmers
- Psyche: A Journal of Entomology
- Ant–fungus mutualism
While the observed vertical transmission of fungal cultivars  and strong host-symbiont specificity   might suggest a tight coevolutionary relationship, recent phylogenetic analyses suggest this is not the case.