Consider the Slime Mold: How Amoebas Form Social Networks

NC: It turns out we’re not the only species that assembles ourselves into networks and gives rise to others sorts of special properties and so to push this point home, this point about emergence, this idea that collectivities can have properties that are not present in the individuals themselves let’s consider a further example.  This is a slime mold.  It is a primitive amoeboid fungus and all this fungus does I digest wood, so this thing lives on the forest floor and if you have ever lifted up like a pile of leaves in the fall and they are wet and soggy and you see those little white tubes under that is what this thing is doing.  The little fungus forms connections to other nearby fungi.  They fuse and they make these long tubes and they digest wood and they distribute the waste from their digestion through these tubes.  But it turns out individuals of this species in connecting to each other form a kind of super organism with unexpected properties.  

For example, they can solve mazes.

So if you take a maze and you put it on a kind of **** plate and you put food at two different spots, the entrance and the exit to the maze and by food here I mean something like wood or like an oat flake.  If you put oat flakes at the entrance or the exit of the maze this simple organism will change its shape and connect to the two sources of food by finding the minimum path length solution between the two points.  If parts of the organism are spread out on the gel they will reassemble to form a kind of single super organism and so it **** a kind of maze solving property, a kind of primitive intelligence that is not present in the individual organisms themselves and this work was done by a Japanese mycologist by the name of Toshi Nagagaki [ph].

So here you are.  Here is the maze.  The amoeboid fungus is bubbling up and connecting to each other.  There is the oat flakes at the entrance and the exit.  It is surrounding the whole plate and you’re going to see that all the paths are going to die back except for the one shortest path through the maze.  In fact, this amoeboid fungus is better able to solve mazes then Toshi’s graduate students, not better than my graduate students thank goodness.  It is able to find the shortest, most efficient path through the maze.  It is able to find the shortest, most efficient path through the maze.  This maze solving ability is an emergent property of the amoeboid fungus.

So it is obviously not a single amoeboid fungus that is solving this maze.  It is the fungi working collectively that give rise to this property, this maze solving ability that emerges from their interactions. 

Obviously if you ask can this amoeboid fungus solve a maze the answer is no, but the maze solving ability emerges as a result of the interactions.  In fact, you can use this kind of maze solving ability or this ability to find the optimal paths to do other sorts of things like here we show an image on the left is the rail network designed by human beings in England and on the right is some work done by my colleague Mark Fricker [ph] at Oxford University.  He took the map of England and he put little oat flakes at every city and he plated the amoeboid fungus and the amoeboid fungus gave rise to a path connecting or a set of paths connecting the oat flakes that actually imitated and in many ways was better than the rail network the human beings had designed over 200 years, so if you look at these two things side by side you see that the fungus is able to design a railway system for England, in fact, a better system than the one that they have.


It turns out we’re not the only species that assembles ourselves into networks, says sociologist Nicholas Christakis. Consider the slime mold.

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This article was originally published on our sister site, Freethink.

China wants to build a mini-star on Earth and house it in a reactor. Many teams across the globe have this same bold goal --- which would create unlimited clean energy via nuclear fusion.

But according to Chinese state media, New Atlas reports, the team at the Experimental Advanced Superconducting Tokamak (EAST) has set a new world record: temperatures of 120 million degrees Celsius for 101 seconds.

Yeah, that's hot. So what? Nuclear fusion reactions require an insane amount of heat and pressure --- a temperature environment similar to the sun, which is approximately 150 million degrees C.

If scientists can essentially build a sun on Earth, they can create endless energy by mimicking how the sun does it.

If scientists can essentially build a sun on Earth, they can create endless energy by mimicking how the sun does it. In nuclear fusion, the extreme heat and pressure create a plasma. Then, within that plasma, two or more hydrogen nuclei crash together, merge into a heavier atom, and release a ton of energy in the process.

Nuclear fusion milestones: The team at EAST built a giant metal torus (similar in shape to a giant donut) with a series of magnetic coils. The coils hold hot plasma where the reactions occur. They've reached many milestones along the way.

According to New Atlas, in 2016, the scientists at EAST could heat hydrogen plasma to roughly 50 million degrees C for 102 seconds. Two years later, they reached 100 million degrees for 10 seconds.

The temperatures are impressive, but the short reaction times, and lack of pressure are another obstacle. Fusion is simple for the sun, because stars are massive and gravity provides even pressure all over the surface. The pressure squeezes hydrogen gas in the sun's core so immensely that several nuclei combine to form one atom, releasing energy.

But on Earth, we have to supply all of the pressure to keep the reaction going, and it has to be perfectly even. It's hard to do this for any length of time, and it uses a ton of energy. So the reactions usually fizzle out in minutes or seconds.

Still, the latest record of 120 million degrees and 101 seconds is one more step toward sustaining longer and hotter reactions.

Why does this matter? No one denies that humankind needs a clean, unlimited source of energy.

We all recognize that oil and gas are limited resources. But even wind and solar power --- renewable energies --- are fundamentally limited. They are dependent upon a breezy day or a cloudless sky, which we can't always count on.

Nuclear fusion is clean, safe, and environmentally sustainable --- its fuel is a nearly limitless resource since it is simply hydrogen (which can be easily made from water).

With each new milestone, we are creeping closer and closer to a breakthrough for unlimited, clean energy.