Earth's hidden super-structure stretches 1 billion times the distance to the Sun

Space · Published 21 October 2026 Swipe more like this →

In short: Beneath your feet lies a fungal superhighway so vast it defies human scale. These invisible networks act as a global circulatory system, moving billions of tons of carbon and sustaining nearly every land plant on Earth. We are only just beginning to map this secret architecture.

The discovery centers on arbuscular mycorrhizal (AM) fungi, a group of organisms that form mutually beneficial partnerships with approximately 70% of all plant species worldwide. Originating over 450 million years ago, these old connections likely played a vital role when plants first moved onto land. In this symbiotic exchange, plants provide fungi with carbon produced via photosynthesis, while the fungi extend thread-like filaments called hyphae into the soil to supply the plants with essential water and nutrients that roots alone cannot reach.

For the first time, researchers have mapped the physical density and global distribution of these networks. The findings reveal that Earth's topsoils contain an estimated 110 quadrillion kilometers (about 68 quadrillion miles) of living fungal filaments. To grasp such a massive magnitude, consider that this span equals nearly 1 billion times the gap between our planet and the Sun. The study identified grasslands as a primary hotspot, with prairies, steppes, savannas, and wetlands collectively housing roughly 40% of the world's AM fungal infrastructure. The Sudd wetlands in South Sudan, the Tibetan Plateau, and the Florida Everglades are expected to host some of the highest densities.

Beyond their structural scale, these fungi are critical regulators of the global climate. They are major players in the carbon cycle, channeling an estimated 3.12 to 4 billion tons of CO2 equivalent from plant photosynthesis into the soil annually. This represents about 11% of all human-related carbon dioxide emissions. Nevertheless, the research notes that people are affecting this framework; it is estimated that average network thickness drops by roughly 50% across extensive farming lands. Such degradation can reduce a soil's ability to cycle nutrients, store carbon, and withstand environmental stress.

The research was made possible by an international effort combining field observations from hundreds of sites across continents with ecological datasets and modeling. To support ongoing conservation, scientists launched the Underground Atlas, a digital platform designed to help identify biodiversity hotspots and help policymakers protect these vital networks. While fungi remain largely overlooked in global biodiversity assessments, this mapping provides a necessary foundation for understanding the hidden biological machinery that sustains our food systems and ecosystems.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?

Related

• The hidden underground networks that sustain nearly all life on Earth
• The hidden network beneath your feet that regulates the Earth's climate
• The invisible architects building Earth's largest and most complex structures
• Before plants had roots, fungi did the job for them
• The Wood Wide Web
• A mysterious methane surge may signal a global climate reversal
• Uncovering the truth behind Antarctica’s crimson-colored Blood Falls
• Insects aren't drawn to light; they are simply lost in the dark
• The evolutionary trade-off that turned T. rex into a head-first hunter
• The wheel wasn't a 'eureka' moment, but a slow engineering evolution
• Antarctica's hidden landscape is a massive, fan-shaped geological structure
• The human appendix is not the evolutionary vestige we once thought

More in Space · Latest · A–Z · All topics