Fly agaric has a long association with fairies and humans
Top photo: A cluster of fly agaric mushrooms show variation of size, shape and color (Photo: Jeff Mitton)
Since the Renaissance, fly agaric has appeared in art and literature, frequently associated with fairies, trolls, wizards, witches and other mystical creatures
The most iconic and easily identified mushroom in the world is Amanita muscaria,or fly agaric. Itgrows around the world at northern latitudes in association with spruces, pines, birches and aspens, with its roots forming mutually beneficial mycorrhizal associations to exchange water and nutrients. It is easy to recognize, for it has a bright red cap, and all else white: stipe (stem), gills (underside of cap) and crumbles of the egg sac on the cap. These bright, contrasting colors make it easy to find and identify in a forest.
Fly agaric's bright, contrasting colors evolved to advertise their molecular defenses, muscimol and ibotenic acid. Unless an herbivore has evolved a way to combat activities of these compounds, these defenses are toxic and hallucinogenic, triggering severe and prolonged vomiting and loss of coordination and balance.
These colorful mushrooms and their psychoactive compounds have been associated with mankind for about 10,000 years. The association started with shamans in northern Europe and Siberia, who used the mushrooms during religious ceremonies to imagine communication with gods, ancestors and spirits. Similarly, they could be an ecstatic inebriant to enliven celebrations of winter solstice and the return of sunlight.
From the 13th through the 19th centuries, fly agaric was commonly used to kill flies in European homes and buildings.Flies were abundant before the invention of screens on windows and doors, and they were dreaded, thanks to a rumor that they get into the head and cause insanity. The practice came about after it was discovered that dried crumbs of fly agaric dropped into milk attracted flies, and when the flies sipped the milk, the ibotenic acid paralyzed and ultimately killed them. The common name fly agaric stems from this practice—agaric is the name for the familiar toadstool-shaped mushroom. Its formal name is Amarita muscaria: Amarita is the genus of mushrooms, and ܲis a reference to the common housefly, Musca domestica.
Since the Renaissance, fly agaric has appeared in art and literature, frequently associated with fairies, trolls, wizards, witches and other mystical creatures in fairy tales and books for children. Recent examples will be most familiar. Dancing red-and-white mushrooms appear in Fantasia. In Alice's Adventures in Wonderland, Alice converses with a hookah-smoking caterpillar sitting on a gigantic red-and-white mushroom. Fly agaric also appears in Snow White and the Seven Dwarf. Smurfs are small, blue, humanoid creatures living in red-and-white, hollowed-out mushrooms.
Laplanders, who use reindeer as work animals, saw their reindeer eat fly agaric and subsequently romp and stagger. Laplander herdsmen believed that reindeer sought fly agaric for its psychoactive reward. The Laplanders also used fly agaric to achieve an ecstatic and imaginative state, and it is possible that they were at the root of the Christmas story of flying reindeer led by a jolly man dressed in the colors of the mushroom who enters a dwelling via its chimney. Perhaps this entry recalled shamans who would enter a dwelling through the smoke hole in the roof, delivering sacks of colorful mushrooms to fuel a celebration. The Christmas Story appeared in 1823 in a poem referred to as "A Visit from St. Nicholas” by Clement Clarke Moore.

A red cap dotted with the dried crumbles of the egg sac make fly agaric easy to find and identify. (Photo: Jeff Mitton)
More than 600 described species in the genus Amanita occupy the full range from deadly (death cap, A. phalloides; destroying angel, A. bisporigera) to delicious (blusher, A. rubescens; Caesar's mushroom, A. caesarea). With so many species and such dire consequences for a mistaken identification, you should be trained before collecting fly agarics from the forest for personal use.
While hiking at the 91Ҹ's Mountain 91Ҹ Station, I came across a cluster of fly agaric mushrooms. I was surprised to find several divots in the cap—something small, the size of a bird or chipmunk, had taken bites. Who was eating fly agaric?
Reindeer have four chambered stomachs with microbial fermentation, which allows them to digest the cellulose in plant cell walls. All ruminants—including cattle, sheep, goats and bison, eat fly agaric without discomfort.
Another group of animals that can enjoy fly agaric with impunity is squirrels (family Sciuridae), and every squirrel species that I checked (pine, grey, fox, golden mantled ground squirrel, rocks squirrels, chipmunks) eat fly agaric and use a unique method to safely pass the toxin. Squirrels have a novel glycoprotein lining in their intestines that immediately binds the toxins, inactivating them, and escorting them the rest of the way through the digestive tract.
Photographers have amply documented foxes gulping down hunks of fly agaric, but they suffer the agony of severe, prolonged vomiting and staggering that omnivores generally experience. Foxes may be sly, but not when it comes to choosing ingredients for a salad.
Meanwhile, turkeys, grouse, crows, ravens and jays eat fly agaric without distress, but many birds suffer both gastrointestinal distress and severe neurological symptoms.
It is thought provoking to discover an area here in Colorado where the bright mushrooms are popping up, for the association of humans and fly agaric has multiple facets and reaches far back into time. Aposematic coloration reliably warns of the defensive substances (muscimol and ibotenic acid), foreshadowing gastrointestinal misery and eruption for some species. Like all other molecular defenses, one or more species have evolved a way around the defenses and evolved to use them either as food or as an intoxicant.
Ten thousand years ago shamans used the same molecules to produce altered states in their followers for ceremonies and celebrations. Artists and writers brought back inspiration from altered states, and today we have enchanting fairy tales and numerous imaginary creatures to entertain and stimulate imaginations. Each year, families drape festive lights and children listen for the sound of hooves on the roof and a cheerful voice encouraging his reindeer.
For scientists, the chemistries of muscimol and ibotenic acid provide insight into chemical ecology of natural populations and enhance the pleasures of a walk in the woods.
Jeff Mitton is a professor emeritus in the Department of Ecology and Evolutionary Biology at the 91Ҹ 91Ҹ. His column, "Natural Selections," is also printed in the 91Ҹ Daily Camera.
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