The early morning sunlight peaks out from behind the Eastern horizon, shining warmly
on the forest canopy. Within minutes, the limited amount of light turns to full rays across the quiet campus. The forest canopy takes in the first of the light, but soon the field awakens as well as the forest floor with the occasional ray of light that peeks through the canopy. The sunlight seems to bring back to life a whole world that was sleeping just minutes ago; however, there’s an entire ecosystem underground. The plants’ roots and their fungal partners never rest; they are
constantly digesting and transforming nutrients to fuel the world we know.
Another world, this time microscopic, full of molecules and pathways, interactions
unseen, fueled by two partners: plants and fungi. Plants take in the morning sunlight, thus
photosynthesizing and creating sugar. The plants fuel their partners with this sugar – a sort of reward for the fungi’s ample supply of phosphorus and nitrogen to the plant roots, which is essential for the growth and development of the plants. The cycle continues, back and forth the
nutrients are digested and transformed, transferred here and there throughout the unseeable
expanse underneath us. All the while, the roots grow and develop.
The roots take in water; the travelling of water both down the tree stem and out of the
leaves pulls water in the opposite direction through the roots and up the trunk, nutrients flowing
freely within. Storage vesicles within the roots stockpile reserves of water and nutrients. The
fungi do the same, storing fuel for when the sun tucks away and they can no longer rely on the
plants’ freshly synthesized sugars for fuel during the long nights. The fungal bodies, mycelia,
grow and enter the roots.
Some fungi rely entirely on sugars outside of the cells, while others are
able to infiltrate the root cells. Those fungi lucky enough to have the capacity to enter and grow inside the cellular matrix of the roots form an even closer kinship to the plant; they rely entirely on each other to deliver the nutrients they require.
This relationship has evolved and progressed so immensely throughout time. Primitive
plants just beginning to grow on land had very little ability to grow root structures. Somewhere
in the evolution of plants, a mutation created the ability for the plants and fungi to fuel each
other. Favoring this mutation, natural selection has caused most plants that we know today to
rely heavily on fungi. Not only are the plants and fungi relying on this mutualism, but humans
and all other organisms do as well. The immense co-inhabitance occurring beneath the ground
keeps entire ecosystems in balance through the assurance of nutrients to plants. This nutrient
supply ensures that the atmosphere retains high enough oxygen levels to sustain life as well as
nutrient-rich soils for other plants, insects, and bacteria.