[REVIEW] : World record in Châteauroux: the Blaise-Pascal high school will create the longest living blob

This is what is called having a sequence of ideas. In September 2021, Nicolas Debrus, biotechnology teacher at Blaise-Pascal high school in Châteauroux, decided to involve the establishment in the #ÉlèveTonBlob project launched by the National Center for Space Studies (Cnes), in partnership with the Scientific Research National Center (CNRS) and the Academy of Toulouse.

The goal: to have students reproduce tests carried out on a “blob” in weightlessness by Thomas Pesquet in the International Space Station. And observe the behavior of “Physarum polycephalum”, true enigma of the tree of lifelocated halfway between animal and plant, long considered a kind of mushroom.

An invitation seized on the fly

But what Nicolas Debrus did not tell us at the time was that, “during a webinar presenting the project, Audrey Dussutour, the researcher at its origin, had launched out loud that if someone was motivated to break the world record for the largest blob, it was easy: it would be enough to merge several pieces of the basic strain in the same place… for example in the center of France!” Words that immediately resonated with Professor Blaise-Pascal, who contacted the researcher.

Seven hundred 5cm pieces to merge

Together, still in partnership with the CNRS, but also with the Association of Biology and Geology Teachers (APBG), they set up a new project: “Big Blob Record“. Namely, the world record for the longest blob. Goal : 30m long !

“To do this, specifies Nicolas Debrus, we will have to align, in a square spiral, no less than seven hundred pieces of blobs. They must first be cut out with a 5 cm cookie cutter in their petri dishes, before healing. Once placed side by side, they will be able to merge in a few minutes”.

World record approved by a bailiff

All this under the watchful eye of a bailiff sent for the occasion in order to confirm the record. “We are also going to contact the Book of Records to have it recorded”, assures Yannick Loiseau, principal of the establishment. Who therefore expects to receive classes from all over France: “The idea is thatas many participants of the #ÉlèveTonBlob project as possible (which mobilized 4,500 classes in France) come with a few boxes of their blob… Those who cannot come can also send them to a referent from their rectorate who will send them to us”.

The incredible powers of the blob

Between her and him, it was immediately love at first sight. She is Audrey Dussutour, ethologist at the CNRS. He is the blob. Apparently, it has nothing going for it: it’s a sticky, shapeless mass that smells rather bad. It takes its nickname from the American film The Blob, in which an alien jelly invades the Earth by swallowing its inhabitants. It was in 2008 that the researcher crossed her path through an Australian colleague. Known since the 17th century, it has been little studied until today. In her Toulouse laboratory, the scientist now devotes herself to this unicellular being – of which she has become one of the world’s specialists. Recently, she published the results of her research in the book Everything You Always Wanted to Know About Blobs But Were Afraid to Ask (Ecuadors ed.). The one accompanying Audrey Dussutour is a bright yellow Physarum polycephalum. But there are other species, white, black, green or pink. Impossible to classify, the blob is neither a plant, nor an animal, nor a fungus. It actually belongs to the division of mycetozoa which includes certain single-celled organisms. In France, it hides in humid forests, on decaying bark or leaves.

Why does the blob fascinate scientists so much?

“He has amazing abilities! A blob is made up of a single cell containing many nuclei: the more these divide, the larger the blob grows. It does not have differentiated tissues such as a nervous system, a mouth, eyes, muscles. And yet he is able to eat, move around, change his behavior, enthuses Audrey Dussutour. He can also learn! » Are there forms of memory and learning based on something other than neurons? This is one of the questions posed by this organization full of surprises, and which motivates the scientist to continue her research. Moreover, the latter rarely leaves her blob, even on vacation. Voracious, it must be fed regularly and constantly monitored to prevent it from growing too large and invading the laboratory…

the blob never Dies

Take a 10 cm2 blob and cut it into 1 mm2 squares: you will get 10,000 healthy little blobs! Cut, a blob heals and closes its membrane in less than two minutes. If it dries out, it goes into a form of hibernation and no longer needs to be fed. To wake him up, a few drops of water are enough. In 1973, a resident of Texas found a blob in her garden and tried to get rid of it: beatings, poison, drowning… Nothing could overcome it.

The blob knows how to fight

In her laboratory, the Toulouse researcher must monitor her blobs like milk on the stove: when they are placed next to each other, they merge to form a single organism. And if they are not genetically identical (i.e. from the same blob), a battle may ensue: the nuclei of the two blobs attack each other, secreting molecules capable of killing the nuclei of the adversary or to prevent them from dividing.

the blob can learn

When this organism without a brain or neurons is placed in a device where a repellent (caffeine, for example) prevents it from going to eat, it ends up getting used to this substance: after six days, it moves towards its meals as quickly as if there were no obstacles. He can then transmit this learning to a congener when he merges with him.

the blob knows how to heal

A blob can become ill: it then becomes covered with mushrooms. The CNRS scientist noted that an infected specimen changes its diet and prefers fatty foods, high in cholesterol, such as egg yolk. Thanks to this diet, the infection subsides in some blobs.

the blob moves

The blob has no legs but pseudopodia: deformations of its membrane which appear in its viscous mass. If it is very hungry, the blob can peak at 4cm per hour… One day, Audrey Dussutour, who hadn’t been able to feed her blobs for a weekend, found them glued to the ceiling, looking for food.

the blob plays with mazes

In 2000, a Japanese researcher, Toshiyuki Nakagaki, placed several blobs in the middle of a maze whose two ends contained food. Surprise: they managed to find the exit. Their secret? As they move, they deposit a kind of mucus. Thus, the blob knows which places of a maze it has already explored without success, which allows it to find its meal more efficiently.

the blob eat everything

The blob revels in bacteria, yeasts or large fungi. Audrey Dussutour feeds her family with oatmeal. Thanks to this diet, they double in size every day. Problem: in two weeks, a blob the size of a coin ends up measuring 17m2! The researcher must therefore regularly cut up her blob and throw part of it in an airtight bin, so that it cannot escape…