Fungal fruiting body. Some fungi, like the yeasts that ferment sugar into alcohol and cause bread to rise, consist of single cells that multiply by budding into two. However, most fungi form networks of many cells known as hyphae (pronounced HY fee): fine tubular structures that branch, fuse, and tangle into the anarchic filigree of mycelium. Fungal like fruiting bodies.
Mycelium describes the most common of fungal habits, better thought of not as a thing but as a process: an exploratory, irregular tendency. Water and nutrients flow through ecosystems within mycelial networks. The mycelium of some fungal species is electrically excitable and conducts waves of electrical activity along hyphae, analogous to the electrical impulses in animal nerve cells.
Fungal fruiting bodies, ecosystems within mycelial networks
Hyphae make mycelium, but they also make more specialized structures. Fruiting bodies, such as mushrooms, arise from the felting together of hyphal strands. These organs can perform many feats besides expelling spores. Some, like truffles, produce aromas that have made them among the
most expensive foods in the world.
Use of molds to treat wounds
Others, like shaggy ink cap mushrooms (Coprinus comatus), can push their way through asphalt and lift heavy
paving stones, although they are not themselves a tough material. Pick an ink cap and you can fry it up and eat it. Leave it in a jar, and its bright white flesh will deliquesce into a pitch-black ink over the course of a few days.
Their metabolic ingenuity allows fungi to forge a wide variety of relationships. Whether in their roots or shoots, plants have relied on fungi for nutrition and defense for as long as there have been plants. Animals, too, depend on fungi. After humans, the animals that form some of the largest and most complex societies on Earth are leaf-cutter ants.
Colonies can reach sizes of more than eight million individuals, with underground nests that grow larger than thirty meters across. The lives of leaf-cutter ants revolve around a fungus that they cultivate in cavernous chambers and feed with fragments of leaf. Human societies are no less entwined with fungi. Diseases caused by fungi cause billions of dollars of losses the rice blast fungus ruins a quantity of rice large enough to feed more than sixty million people every year.
Fungal diseases of trees, from Dutch elm disease to chestnut blight, transform forests and landscapes. Romans prayed to the god of mildew, Robigus, to avert fungal diseases but weren’t able to stop the famines that contributed to the decline of the Roman Empire. The impact of fungal diseases is increasing across the world: Unsustainable agricultural practices reduce the ability of plants to form relationships with the beneficial fungi on which they depend.
The widespread use of antifungal chemicals has led to an unprecedented rise in new fungal superbugs that threaten both human and plant health. As humans disperse disease-causing fungi, we create new opportunities for their evolution. Over the last fifty years, the most deadly disease ever recorded a fungus that infects amphibians has been spread around the world by human trade. It has driven ninety species of amphibian to extinction and threatens to wipe out over a hundred more.
The variety of banana that accounts for ninety-nine percent of global banana shipments, the Cavendish, is being decimated by a fungal disease and faces extinction in the coming decades. Like leaf-cutter ants, however, humans have worked out how to use fungi to solve a range of pressing problems. In fact, we have probably deployed fungal solutions for longer than we have been Homo sapiens. In 2017, researchers reconstructed the diets of Neanderthals, cousins of modern humans who went extinct approximately fifty thousand years ago.
Penicillin became the first modern antibiotic
They found that an individual with a dental abscess had been eating a type of fungus a penicillin producing mold implying knowledge of its antibiotic properties. There are other less ancient examples, including the Iceman, an exquisitely well-preserved Neolithic corpse found in glacial ice, dating from around five thousand years ago.
On the day he died, the Iceman was carrying a pouch stuffed with wads of the tinder fungus (Fomes fomentarius) that he almost certainly used to make fire, and carefully prepared fragments of the birch polypore mushroom (Fomitopsis betulina) most probably used as a medicine. Mushrooms fruiting bodies.
The indigenous peoples of Australia treated wounds with molds harvested from the shaded side of eucalyptus trees. The Jewish Talmud features a mold cure, known as “chamka,” consisting of moldy corn soaked in date wine. Ancient Egyptian papyruses from 1500 BCE refer to the curative properties of mold, and in 1640, the king’s herbalist in London, John Parkinson, described the use of molds to treat wounds.
But it was only in 1928 that Alexander Fleming discovered that a mold produced a bacteriakilling chemical called penicillin. Mushrooms fruiting bodies for medicine.
Penicillin became the first modern antibiotic and has since saved countless lives. Fleming’s discovery is widely credited as one of the defining moments of modern medicine and arguably helped to shift the balance of power in the Second World War.