What is the largest unicellular organism

This organism has no brain, but almost 720 genders

The Paris Zoo presents an organism that looks like a mushroom but behaves like an animal: it can digest food and is capable of learning. The unicellular organism, called the blob, is also remarkable in other ways. However, it is by no means as mysterious and new as it is portrayed.

Outwardly it is reminiscent of a mushroom, but the so-called blob is neither a mushroom nor a plant. The yellowish protozoan has no eyes and no brain - and can still recognize food. The blob also has no mouth and no stomach, but can still digest food. So it behaves similarly to an animal.

On Wednesday, the new organism was presented by the Parc Zoologique de Paris, where it can also be viewed by visitors from Saturday. "The blob is one of nature's secrets," said Bruno David, director of the Paris Natural History Museum, which also includes the Parc Zoologique.

He can learn and transfer his knowledge

In fact, the unicellular organism has some remarkable properties. For example, it moves without legs or wings. If it is cut in half, the injury heals within two minutes.

The blob reproduces by means of what is known as conjugation. In contrast to animals, whose cells fuse during reproduction, the genes are transferred through direct cell contact. In this way, there are not only two sex types, as with animals, but a multiple. The blob has almost 720 mating types. It enables the organism to reproduce with as many other specimens as possible.

"It surprises us that he can learn even though he has no brain," said Bruno David to the Reuters news agency. This, too, is a typical characteristic of animals. Even more: If you bring two blobs together, one transfers what he has learned to the other.

Not a newly discovered organism

"The organism behaves very unusually for something that looks like a mushroom," says David. One could not say with certainty whether it was an animal.

Lukas Schärer, environmental scientist at the University of Basel, can only smile at these statements. "It's ridiculous to pretend you don't know where the organism belongs." The unicellular organism is assigned to the eukaryotes, more precisely the amoebozoa. "These have been known for decades." There are numerous organisms that cannot be assigned to either animals or plants.

Nevertheless, Lukas Schärer is delighted that a zoo also exhibits organisms other than animals.

The single cell owes its name to the science fiction film of the same name from 1958 with Steve McQueen, in which an extraterrestrial creature devours everything that comes in its way.