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Blob (Physarum polycephalum) © MNHN - F.-G. Grandin

The many-headed slime

It’s not a plant, nor an animal, nor a mushroom... The many-headed slime is definitely out of the ordinary! This single-celled organism has incredible properties which have shown great promise in enabling major scientific breakthroughs to be made.


Class, order and family :
Myxomycetes, physarales, physaraceae
Vitesse de déplacement :
1 to 4 cm/h
Living environment :
Dark and damp spaces
Diet :
Fungus spores, bacteria, microbes


Well-sheltered in the dark and damp spaces that it inhabits, the many-headed slime knows how to stay under the radar. This single-celled being has some astonishing abilities. Even though it has no mouth, stomach or eyes, it is perfectly capable of detecting the presence of food (fungus spores, bacteria and microbes) and ingesting it. Despite not having any legs, feet or wings, it can still move up to 1 cm/h by stretching out its membrane. And if you cut it into pieces, the many-headed slime will heal in two minutes! It doesn't have just 2 sexual types, it has close to 720. And the most amazing thing is its ability to solve problems, exhibit different personalities and even communicate, despite the fact that it doesn't even have a brain!

This extraordinary living being is virtually immortal, its only fear being light or drought. In the event of danger, it dries, but at the slightest hint of water it’s back again!

Distinctive features

In good conditions, the many-headed slime grows very quickly and can double in size every day. Myxomycete can be red, white or pink, although the best known is the bright yellow Physarum polycephalum.


One morning in 1973, not far from Dallas in Texas, Marie Harris discovered something strange in her garden, which she described as “frothy, creamy and pale yellow, similar to an omelette, no bigger than a cookie”. She didn’t worry about it to begin with, thinking it was just a mushroom. But just two weeks later she is horrified to see that it is growing in a rather disturbing way. She makes a decision - grabbing her rake, she scatters it around her garden. However, the mushroom reappears two days later, regenerated. Her husband then gives her a hand and crushes it with a stick. This doesn't work either, so they decide to poison it with a herbicide, but this proves to be ineffective. The police are called to help out, and they bombard the intruder with high-pressure water and pelt it with gunshots! The pest survives each and every attack and seems to be invincible. The despairing couple give up their arms when, suddenly, the immortal enemy disappears without a trace. An alien, it must have been an alien, thought Marie Harris and her husband. It was the only logical explanation. In reality, they had simply come across a harmless myxomycete, which is sometimes known as the “blob”, in reference to the film The Blob, directed by Irvin S. Yeaworth Jr and starring Steve McQueen.

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