The most important novel in the history of the Earth
Throughout time, green plants, with their astonishing diversity, the majesty of trees, and myriad flowers, have captivated human eyes and sparked curiosity. This led to plants (along with even more eye-catching animals) always being more researched and receiving more resources and attention for their protection. However, plants would not exist without representatives of another kingdom – fungi. So, I invite you to read about the most important romance in Earth's history, which led to the flourishing of flora and all terrestrial life.
A LONG, LONG TIME AGO...
600 million years ago, algae, the ancestors of all terrestrial plants, ventured onto land. In comparison, we, humans, diverged from similar primates about 4-8 million years ago. Before plants flourished on land, Earth had rather extreme conditions – temperatures fluctuated greatly, and rocks and dust prevailed. There was no fertile layer similar to soil. Minerals and other nutrients were locked within rocks. However, there was still some life on land even then – mostly photosynthetic bacteria, extremophile algae, and fungi. But given the harsh conditions, all other life teemed in the water. On land, the greatest opportunities were for organisms that fed on sunlight and CO2 (photosynthesizing) and could withstand harsh conditions. But the algal ancestors of plants at that time, although capable of photosynthesis, lacked roots, so they could not absorb and store water, which would have allowed them to establish themselves further from water sources. Moreover, they could not extract additional mineral nutrients from rocks. So how did they manage to conquer land and proliferate into a kingdom occupying approximately 80% of the world's living mass?
NO ONE KNOWS HOW, BUT THEY MET
When it comes to theories of the origin of life, scientists have different hypotheses, as there is often a lack of evidence to firmly support any single one. However, regarding the flourishing of algae and their eventual transformation into powerful vegetation, science does not dispute and agrees that the union with fungi helped these tiny plants flourish more than their superpower of photosynthesis! No one fully knows how this romance between fungus and algae began, but their love story is evidenced by imprints in fossils dating back approximately 400 million years. And it was not some fleeting infatuation; on the contrary, it was a well-calculated partnership that passionately continues to this day. Imagine, almost all plants (over 90%!) live together with some fungus (or fungi). And although, as we say, "there's no smoke without fire," even in such a partnership matured over millions of years, anything can happen – competition and conflicts – but more often, they share what they acquire.
CREATING MUTUAL WELL-BEING
This partnership was christened "mycorrhiza" (Latin: Mycorrhiza - rhyza root, mykes - fungus). Fungi, with their mycelium composed of thin, intertwined hyphae, acted as roots for algae. For this union to thrive, both partners must contribute to their shared well-being. During photosynthesis, the plant captures carbon from the atmosphere and produces various carbon compounds (sugars and proteins), which are important energy sources. And the fungus, with its hyphae carefully intertwined with the plant's roots, gains direct access to this bounty, which it then feeds on. But this is not enough for either the fungus or the plant. For complete happiness, they still need water and mineral nutrients hidden in the labyrinths of the soil. And this is the domain of the fungus, whose penetrating, thin hyphae can reach minerals and water wherever they may hide. Thus, the plant also benefits from this union because the fungus shares its "hunted" minerals and additional water.
HUNDREDS OF MILLIONS OF YEARS OF INTIMACY
Over millions of years, plants became increasingly complex, larger, and more diverse since the fungus and the green lump of algae, without roots or other elaborate structures, met each other. And although today plants themselves have roots that have evolved to be very similar to fungal hyphae, their roots still do not surpass mycelium in their ability to capture minerals from the soil. Hyphae are at least 50 times thinner than the thinnest plant roots, and when intertwined with them, they expand the root surface area up to 100 times. Just as hundreds of millions of years ago, the relationship between fungus and plant remains very close and intimate today. If we were to look at the tips of plant roots under a microscope, it would be difficult to distinguish where the plant ends and the fungus begins. The tiny fungal hyphae penetrate inside the roots, between plant cells (in some cases, even entering the cells), and entangle them. The plant roots transition into the mycelium and continue their journey through the labyrinths of the soil.
THE MYCORRHIZAL CARPET BENEATH OUR FEET
When we walk in the forest, we are in the mycorrhizal world of trees and fungi. One could say we walk on a mycorrhizal carpet in the forest, which lies hidden in the soil. Hyphae can constitute from one-third to half of all living mass in the soil. If, for example, we were to pick up a teaspoon of healthy forest soil, we could uncoil about 1000 meters of hyphae from it (Dr. Aidee Guzman)! And another cosmic illustration of the abundance of hyphae: if we were to stretch out the hyphae of mycorrhizal fungi (these are the same ones that live in association with plants) found in the world, in approximately the top 10 centimeters of soil, we would get a hypha of an almost incomprehensible length, about half the width of our galaxy (4.5 x 10 to the seventeenth power kilometers of hyphae)! And if we were to flatten these hyphae into a plane, we could cover the entire surface of the Earth 2.5 times! And let's not forget that we only measured 10 cm of soil!
Thus, two very different organisms – fungus and plant – combining their superpowers, allow each other to thrive.
The story is based on: "Entangled Life," Merlin Sheldrake
