Scientists mapping underground fungal networks estimate that arbuscular mycorrhizal threads stretch for 110 quadrillion kilometres worldwide, according to a study published in the journal Science. This global digital map reveals that these carbon-rich mycelial networks intersect with roughly 70 percent of Earth’s plant species, playing an essential role in terrestrial ecosystems by exchanging nutrients and regulating the climate.
Mapping the Global Scale of Mycelial Networks
To calculate the total expanse of these subterranean structures, an international research team compiled a global dataset of arbuscular mycorrhizal (AM) fungal density and biomass. The resulting estimate calculates that AM fungal networks span more than 621 trillion miles, or 110 quadrillion kilometres.
To put this vast scale into perspective, the distance from Earth to the Sun is roughly 93 million miles, while Pluto orbits about 3.6 billion miles away from the Sun.
Symbiotic Relationships and Ecosystem Functions
Arbuscular mycorrhizal fungi belong to an ancient group of soil organisms that have formed symbiotic relationships with plants over the past 475 million years. Because fungal cells lack chloroplasts and cannot conduct photosynthesis, they rely on plants for carbon. In exchange, the fungi support plant sustenance.
According to research highlighted by New Scientist, Justin Stewart at the Society for the Protection of Underground Networks notes that these fungi act as crucial partners for terrestrial flora. Mycelial threads are thinner than most plant roots, allowing them to contact a greater volume of soil. This morphology helps the fungi absorb water and essential nutrients and redirect them back to host plants.
Investigating Fungal Intelligence and Pattern Recognition
Beyond nutrient exchange, recent studies explore whether certain fungal networks display forms of intelligence or pattern recognition. Researchers incubated the fungus on wood blocks and arranged them in circles and crosses on soil plates.
Over several months, the mycelium networks in the circle group avoided sending connections through the center, directing shoots outward instead. This behavior indicates that the organisms could detect where food opportunities lay. Yu Fukasawa, a researcher on the study, described this capability to Science Focus as an intelligent response to environmental surroundings.
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