Meet "The Blob", A Brainless Intelligent Slime Mold With 720 Sexes On Display At Paris Zoo


Tom Hale

Tom is a writer in London with a Master's degree in Journalism whose editorial work covers anything from health and the environment to technology and archaeology.

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Physarum polycephalum, a very strange beast indeed. CC/Public Domain 

The Paris Zoological Park will soon showcase what might be one of the weirdest life forms on planet Earth.

On October 19, the zoo is opening a new exhibition containing a slime mold, known as “the blob”, a vibrant yellow collection of brainless organisms with a taste for solving mathematical puzzles and a bizarre sex life. 


Despite its name, it’s not actually a mold, a fungus, a plant, an animal, or a bacterium. It belongs to a kingdom of life called Protista that contains any single-celled organism that is not an animal, plant, or fungus. 

Its scientific name, Physarum polycephalum, means many-headed slime. It's not a single creature, but a collection of unicellular organisms that can band together in a single form. They can be chopped into many pieces, only to fuse back together within a few hours. If they come across any other slime molds along their travels, they will join together.

There is neither a male nor a female of the species, but more than 720 different sexes.

“It is diploid: its chromosomes go in pairs. Then, when it forms spores, each is haploid: a cell contains only one copy of each chromosome. So far, everything is going as for us," Audrey Dussutour, a slime mold expert at the French National Center for Scientific Research (CNRS), explained in a recent interview with CNRS Le Journal.


“If the conditions are right, these spores 'germinate' and there comes [sic] a tiny amoeba. In a liquid medium, this amoeba is equipped with two flagella to move and goes swimming in search of an amoeba of the opposite sex to reform a diploid cell by fusion," she added. "There is not a male or a female, but more than 720 sex types in the blob."

The slime mold is able to creep from place to place at around 5 millimeters per hour by extending stringy finger-like protrusions. Although it has no mouth, it’s able to eat through phagocytosis, a process by which a cell uses its plasma membrane to engulf a large particle. You can typically find them in damp woodland environments, lurking on top of a wet log or some leaves. 

The slime mold has neither a brain nor a central nervous system, nor any neurons. Nevertheless, some scientists argue they exhibit intelligence since they can "learn" from experience and change their behavior accordingly. A recent study showed that slime molds will eventually learn to avoid caffeine, a harmless but offensive substance, through a simple form of learning called “habituation.” They can even pass on this ”knowledge” to new cells when they fuse and join the blob.

Another study even suggested they can "solve" the Traveling Salesman Problem, a tricky math problem commonly taught to college students. 


Let's just hope the blob's enclosure is tightly sealed and closely guarded... 


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