Slime, which doesn't even have a brain, can actually plan city routes

You must be familiar with slimes. Their names often appear in novels and animations. If you play a lot of games, you can also find them in the game.

The popular image of slime is a soft, jelly-like monster that is opaque or translucent and can change shape, split and merge.

Because of its simple form and silly appearance, it is often labeled as a low-end monster. In the game, it always plays the role of a helpless monster in the initial level.

But in fact, slime also exists in our real life, and it is not a simple existence.

The prototype of slime in reality is a magical little creature called slime mold.

Don't feel disappointed. Although slime molds don't even have brains, the strangeness and wisdom they display are amazing.

First of all, in terms of classification, it is a headache for scientists. Slime mold is not a bacterium, but a eukaryotic organism. They go through two completely different forms in their life.

During the growth phase, slime molds are a mass of protoplasm without cell walls in the shape of snot. This is their "metamorphosis stage" because at this stage, both their activities and their food intake are similar to those of protozoa amoeba.

At this stage, slime molds exhibit many characteristics that only animals have, so some biologists believe that slime molds should be classified as protozoa.

However, unlike animals, slime molds also have a collective consciousness. When food is scarce, slime molds will send signals to their companions around them, calling them together to form a large group of slimes and hunt together.

Once the growth period is over, slime molds will show fungal characteristics again. This is their reproductive period, also known as the "fruiting body stage." During this stage, slime molds gradually grow spores with fibrous cell walls and reproduce sexually.

During the reproductive period, slime molds will slowly change into mushroom shapes, harden, and dry up, so another group of biologists asked to classify them as fungi.

Finally, because the discussion was fruitless, this strange creature was simply classified directly into the protozoan kingdom and belonged to the myxomycetes phylum. Although it is a bit broad, it is not wrong after all.

But apart from the difficulty of classification, the most amazing thing about slime molds is their unique skills.

Slime mold is a simple single-celled organism, but it has powerful computing and mobility capabilities and can form complex network systems.

The first to discover these abilities of slime molds were Nakagaki and others from Hokkaido University in Japan. At the time, they replaced the petri dish of slime molds with a small maze, and then placed their favorite food, oatmeal, at the entrance and exit of the maze. Then they observed the slime molds' actions.

At the beginning of the experiment, the slime molds continued to demonstrate their exploration ability in the new environment, gradually expanding their territory and stretching their cytoplasm until every corner of the maze was covered.

After discovering the food, the slime mold quickly reacted between the two food sources, retracted the cytoplasm in the dead end, and chose the shortest of four routes of varying lengths that could connect the two food sources and began to eat frantically.

This phenomenon surprised Nakagaki and his colleagues, and in order to verify whether this ability of slime mold was accidental, they created more different mazes for the slime mold. Without exception, the slime mold chose the shortest path that could connect to food without hesitation in each maze.

Once this experimental phenomenon was announced, it attracted the interest of many scientists. They did not expect that these primitive organisms without brains and nervous systems could actually walk through a maze.

But just being able to walk through a maze is nothing, I also have this skill. Their computing ability is what I really admire.

This unique skill of theirs was also discovered based on a maze experiment. However, the experimenters raised the difficulty level by giving slime molds multiple food sources to see how they would react.

Sure enough, the slime molds that were highly anticipated did not disappoint everyone. The networks they formed by connecting various food points were almost all the best engineering routes.

So the researchers from Hokkaido University had a sudden idea to move slime mold into the "city map".

They placed oatmeal in a moist petri dish shaped like the outline of Tokyo, with the various points placed proportionally to mimic the locations of various cities surrounding Tokyo, and then placed the slime mold on the "Tokyo Station" in the center and let it grow outwards.

They then watched as the slime mold continued to self-organize, spread outward, and gradually optimized its layout to form a stable network over more than 20 hours. This network is comparable to the real-world Tokyo railway network in terms of efficacy, reliability, and cost.

The Tokyo railway system is one of the most rationally planned and efficient systems in the world, and it is the result of decades of hard work by countless engineers. However, it was "perfectly reproduced" by slime molds without even a brain in just over 20 hours.

In order to fill their stomachs, the greedy slime molds have explored the easiest and most labor-saving way to survive, and smart humans have also borrowed this superpower of slime molds as a reference for urban planning.

As a fungus myself, I have to admit that slime mold is more powerful in this regard.