My Brilliant Science Fair Project in 1978

There are a lot of myths about fungi, silly ideas stimulated by slivers of experimental data and stoked by unscrupulous investigators before they flow into the river of online mycological bullshit. The medicinal powers of mushrooms are a prime example, followed by the stoned ape theory, and the miraculous properties of the fungi to reverse the disastrous impact of the selfish ape on the biosphere. A more niche claim, but one with remarkable staying power, is the idea that dark-pigmented molds are attracted to sources of ionizing radiation and can fuel their metabolism by absorbing this form of energy. Anyone with a modicum of education in chemistry and physics should laugh at this proposition. Photons of blue and red light excite the electrons in chlorophyll molecules and energize most of the nutrient cycles on earth. Redox reactions involving a variety of elements are also significant in prokaryote chemistry and provide an alternative chemosynthetic source of primary production to photosynthesis. Ionizing radiation is far too powerful to be harnessed by living organisms to fix carbon. It breaks molecular bonds and displaces electrons from atoms. This is why particles released from radioactive elements are so hazardous for individual organisms, although their role in mutagenesis plays a central role in evolution. There is some experimental evidence for the resistance of melanized fungi to higher doses of ionizing radiation than non-pigmented fungi, but the case for fungal radiotropism (attraction to sources of radioactivity) is very weak, and the concept of fungal radiotrophism (the use of radiation as an energy source) is delusional. Fungal radiosynthesis rather than radiotrophism, broadens the possibilities for the use of ionizing radiation from its use as a primary energy source to its capacity to generate reducing compounds (sources of energized electrons) that could be involved in metabolic reactions. Again, there is no experimental evidence for this. I could invest a week or two in writing a review article to reinforce these points, but I doubt that this would squash the enthusiasm of the chattering classes on social media. As I have written elsewhere, there is an event horizon in mycological thinking that is crossed when enthusiasm and ego exceed experimental evidence.

And eternity in an hour.

"Invisible yet mighty!"

Paradise Lost is the greatest English poem. It is a triumph of humanity in the same literary league as the Iliad , Odyssey , and Aeneid . On second thought, the comparison is off beam. Milton’s epic is greater than these points of departure. It stands alone, high eminent, as the most insightful and beautiful rendering of the human condition in print. It does much more than Milton’s feigned plan to “justify the ways of God to men,” asserting, instead, the ways of men to God, and, as it flows, eclipses all the divinations of Greek and Roman gods. Even a brief dip into the poem has the inspirational power of a clear sunrise on a brisk winter morning, when breath turns to steam and the reappearance of our orange star sanctions a day of glorious possibilities. We are the beneficiaries of Eve’s act of rebellion. She ate the fruit, Adam followed, and, for better and for worse, “The world was all before them.” It is, to be frank, a work of dazzling artistry. All of Titian is its painted equivalent. Little else in the history of Western artistic expression comes close, although Bach wrote some nice tunes and Ingmar Bergman’s The Seventh Seal is a very good film. Readers tend to personalize the poem, absorbing particular scenes and lines that resonate for reasons of individual taste and concerns. My devotion to Satan’s pain as the voyeur in Eden, reflects some loneliness on my part I suppose, the sense of being a lifelong outsider. On a more uplifting note, Milton’s descriptions of Eve’s naked beauty and the afterglow following the consummation of their marriage will haunt me until my thoughts are no richer than those of a potato. These, lulled by nightingales, embracing slept, And on their naked limbs the flowery roof Showered roses, which the morn repaired. Sleep on, Blest pair! (Book IV 771-774)

The evolutionary kinship of the fungi and animals is indicated by their combination into a single supergroup of organisms called the opisthokonts . This uninspiring term refers to the arrangement of shared cell structures called cilia. I suggest that we adopt a more evocative name: mycozoans .

[Image of amoeba adapted from A. Cassiopeia Russell, et al., Frontiers in Microbiology 14 (2023):1264348.] A brain-eating amoeba called Naegleria has received a lot of recent media coverage, including the tragic deaths of a 12-year-old boy in South Carolina who swam in a local reservoir, and a 71-year-old Texas woman who had flushed her sinuses with a neti pot. Using anything other than sterilized water in a neti pot is a proven hazard, but should we be concerned about splashing around in lakes and rivers? This post describes the infection process, explains why cases of this terrible illness may be increasing, and considers the risks of summer recreational activities in our rivers. There have been fewer than 200 cases of this infection in America in the last 50 years and all of these deaths resulted from the nasal inhalation of warm water contaminated with the microbe. There are thousands of species of microbes that we call amoebas because they crawl in a similar fashion to the iconic “classroom” amoeba, Amoeba proteus , which is recognized from the simplest drawing of a wavy outline with a dot in the middle. Naegleria is as distantly related to Amoeba as a rhinoceros is to a rhododendron, but it moves in the same shape-shifting fashion. Unlike the schoolroom amoeba, however, Naegleria can also swim by sprouting a pair of flagella. At one time it was thought that the frisky swimming stage was the one that infected humans, but the crawling cells that gather at the surface of the water are actually more dangerous because they are positioned perfectly for snorting high into the nasal cavities of swimmers. The migration of the amoebas from the nose to the brain is circuitous because the head jelly is enclosed in the skull, wrapped in membranes called meninges, and protected by a formidable tissue layer called the blood-brain barrier that separates the bloodstream from the central nervous system. Trauma to the head that damages these shields can lead to infections, but even an uninjured nose is an anatomical liability for anyone who encounters a pathogenic amoeba. This does not mean that everyone who inhales water carrying the amoebas will become infected—far from it. Mucus that lines the nasal sinuses works as a sticky trap and antibodies bind to the amoebas interfering with their attempts to attach to the tissues underneath. The amoebas are also attacked by white blood cells called neutrophils as they try to get a good foothold on the sinus tissues. As the neutrophils close in, like bloodhounds set loose on fugitives, the amoebas reshape their membranes into suction cups and tear into the fleshy tissues of the sinuses to escape. The odds are stacked against the amoebas, but any that follow the nerves that snake through perforations in the bony roof of the nose have the chance of reaching the brain. The escapees leave the neutrophils howling in the sinuses and the prognosis for the swimmer is grim. Headaches, fever, neck stiffness, nausea, and vomiting occur within as little as a day after exposure, and the symptoms proceed to light sensitivity, seizures, hallucinations, coma, and death. Physicians call this brain infection primary amoebic meningoencephalitis, or PAM. Treatments are very limited. A drug called miltefosine that has been used to treat a tropical disease called leishmaniasis for more than 20 years is showing promise as a new medicine for PAM patients. This makes sense because the parasite that causes leishmaniasis belongs to the same supergroup of microorganisms as Naegleria . The importance of finding treatments for PAM is increasing with the concern expressed by epidemiologists that these infections are likely to become more common as the planet gets warmer and the geographical range of the microbe widens. Warming lakes and rivers will certainly advantage this amoeba, which is happiest in water with temperatures between 30 and 42 degrees Celsius, or 86 to 115 degrees Fahrenheit. Naegleria fatalities have already been reported in India, China, and Southeast Asia. Countries with cooler climates may not escape from this public health threat. Water used to cool nuclear and conventional power plants can support high levels of the amoeba, which represents a source of potential infections when the heated water is discharged into rivers and lakes. The Centers for Disease Control recommends holding your nose shut or using a nose clip if you jump or dive into a river. This provides little comfort. We know that the amoeba finds its way into the brain from the nasal passages, but the rarity of the infection suggests that there may be more to this than inhaling the microbe through the nostrils. Neti pot users increase the pressure within their nasal passages as they rinse and expel water, which may have the effect of forcing the microbe into these sensitive tissues. This leads me to wonder whether swimmers could be safer without nose clips, because closure of the nostrils prevents the reflexive expulsion of water pushed into the back of the throat. Knowledge of the amoeba leaves us with a feeling of unease. The development of primary amoebic meningoencephalitis after playing in a river or lake is less likely than drowning, but this fact is of little comfort to anyone who contracts the brain disease. So, what do we do? Shrug our shoulders, hope for the best, fear the worst, and jump from a rope swing into the river. After all, amoebas and other microbes are everywhere and will outlive us by an eternity.

A screenplay by Matthew R. Riffle and Zackary D. Hill based on my 2017 novel, The Mycologist: The Diary of Bartholomew Leach, Professor of Natural History , is an official selection at the 2025 Cindependent Film Festival: https://www.cindependentfilmfest.org/ Wanda Sykes must be cast to play Phoebe Smith, Queen of Claysburgh. Excerpt: When Cates and I rode across the field, Phoebe Smith knocked out her pipe to prepare for battle: "Dare you is you damned whale; Cates haul you in again from offshore? You bin lying there sunnin your fat belly in Christ’s Sun I spose, hopin for a reeel high tide to pull you back to your damned porpuss-whore of a mother." I looked at Cates in utter amazement. He shrugged his shoulders and dismounted.

Dr. Gemma Anderson-Tempini is an artist working on a project about the mycobiome for a museum commission in Exeter in England. She asked several mycologists to “draw the mycobiome,” to help stimulate her thinking. This is my first draft in which I concentrated on the problems caused by fungi that live on the body. I could draw an alternative view to show that many of the same fungi are also part of the healthy microbiome. Interactions between fungi and bacteria is part of this story. Another approach would be to draw a mother nursing a baby and highlight the fungi in breast milk and the developing mycobiome of the infant.

With head-scratching among consumers about the sources of medicinal mushroom products, a reliable definition of a mushroom seems useful. Clarity is important because many of these “medicinals” come from mycelia instead of mushrooms and their chemical composition can be quite different. Here is my two-part definition. Mushrooms are the fungal equivalent of the fruits produced by plants. They release microscopic spores rather than seeds. We often refer to mushrooms as fruit bodies. Mushrooms are the reproductive organs of fungi. Their spores germinate to form feeding colonies called mycelia that grow as networks of branching filaments called hyphae. Mushrooms develop from mature mycelia to complete the fungal life cycle.