Slime!

It all began with the whales, humpback whales, during the Summers of Love (1967 – 1970). Somebody noticed the gorgeous melodies coming from this species of sea mammal… and recorded them. 

Whale-song quickly became a chart topper. I mean, what else are you going to listen to, midday in your darkened flat, smoking ‘weed’ with friends? It’s either Led Zeppelin or it’s the whales. (This was the ‘60s after all!)

Next question: Why? Why do whales sing? Why do their melodies co-evolve over time? Are they communicating? Communication requires information and intent, a function of mind. Perhaps whales are not mindless automata after all. Perhaps they have their own language, their own topics of conversation, their own minds. 

Et viola, a few tokes and the entire fabric of the biosphere is unravelling like Laertes’ shroud.  If whales are conscious, what about dolphins? And the race is on! Jane adds gorillas to the mix and therefore bonobos, chimpanzees, and other primates. 

Homophiles quickly move in to limit the damage: “Primates and sea mammals only!” But then along comes octopus, parrots and crows. Surely then, we can agree, “Animals only! I mean, they’ve got to have a brain, a central nervous system, right?” 

Apparently not. Soon symptoms of consciousness were noted in trees, forests, and the Wood Wide Web (fungi). And what about our single celled cousins? There is no containing this tidal wave. 

And how about me? (A question that is always appropriate!) Am I one conscious organism, made up of dozens of conscious organs, made up of 30 trillion conscious cells? 

We’ve come a long way, baby! From ‘little less than angels’ (Heb. 2: 7, Psalms 8: 5) we have been reduced to ‘little more than bacteria’. Now, thanks to Ancestary.com, you can add another member to your cognitive family tree. You should be so proud! Turns out you are 2nd cousin, once removed, to…wait for it…Slime Mold!

“Brother Sun, Sister Moon, Cousin Slime.” – St. Francis (2025 update)

A recent article in Knowable Magazine (2/11/2026) spells it out:

“Some slime molds of the species Physarum Polycephalum consist of one giant, pulsating cell that keeps changing shape as it moves around and branches out to access food and avoid unpleasant things like salt or light. 

“But it took a 2010 experiment led by Japanese biologist Toshiyuki Nakagaki of Hokkaido University to reveal the depths of its sophistication. When Nakagaki placed the oat flakes that Physarum likes in a pattern mimicking the cities surrounding Tokyo, the slime mold’s branches almost exactly reproduced the efficient transport connections between them that humans had taken years to develop.”

Wait up! You’re telling me that a unicellular, brainless mold solved the Travelling Salesman Problem (TSP)? And in hours, not decades? Apparently so…with caveats. Slime doesn’t care about precision. It cares about utility. Therefore, it shoots for the quickest possible solution within a functionally acceptable range of accuracy (91% - 96%).

This range is a great example of natural selection at work. Accuracy contributes selective advantage; but so does efficiency. Evolution ensures that Slime Mold achieves an optimum balance between the two values. (Note: There may be more than one set of optimum values; the set of all optimum values is called a Pareto Frontier.)

Survival is a function of task achievement (food) and energy conservation (rest). Did I get enough food? Ok, but did I expend too much energy getting it? Oops!

Natural selection also ‘considers’ a third variable, flexibility, i.e. future adaptability. A perfect solution that is too precious can leave the organism defenseless in the event of a shift in the environment; and since such change is an eventual certainty, inflexible solutions are dead ends, emphasis on dead.

Slime’s 4% - 9% ‘wiggle room’ allows it to arrive at a functional solution within a practical time frame (a few hours). Wiggle room also makes the slime’s solution more flexible and therefore more adaptable to changes in underlying  conditions. 

Example: Suppose Tokyo decided to close a station, a supercomputer (like the Concorde TSP Solver) would have to start from scratch; Slime Mold might not need to make any adjustment at all (to remain within the 91% fault tolerance), but if it did, it would require minimal time and energy. Slime builds on past experience; computers cannot, they have no past. 

So all and all, how do our two heavy weight champions stack up? In one corner we have the Concorde supercomputer (or its equivalent); in the other, we have a unicellular organism known as Slime Mold. Should be a doozy! Haven’t seen a battle like this since a tortoise challenged the great Achilles to a road race.

Nakagaki tested Slime Mold against a supercomputer based on the 25 nodes (stations) that constitute the Tokyo area railway system. Both were asked to optimize routes for several different variables simultaneously, understanding that there could be more than one ‘right answer’ along a Pareto Frontier. Note: There are 10^32 possible solutions.

So, how’d our champs make out? 

• The ‘Concorde’ solved the problem in several hours with 100% accuracy. Bully!

• The Slime Mold solved the problem in the same (or less) time but achieved only 91% – 96% accuracy. By design!

• Because it is more fault tolerant, mold came up with attractive solutions (i.e. points on or near the Pareto Frontier) that the computer had to rule out.

So? A draw? Not even close. It’s a knockout! And the winner is…

But first…back to Tokyo: Over the next, say, 100 years, how many times will there be changes, temporary or permanent, to the railway network: stations closed, stations opened, lines extended? Plus short term reroutes to accommodate construction and repairs. Ok, but we need our solution to work 24/7/365. 

Slime Mold will adjust to each of these changes in a matter of minutes; Concorde will need the full several hours, each time. Eventually, the wasted energy cost will swamp any gain in accuracy. Slime builds on the past; Concorde has intelligence…but Slime Mold has wisdom. 

The supercomputer is never a viable long term strategy, at least not in a world with finite energy resources. Stick with it only if you’re satisfied with an answer that is static and therefore correct ‘only for one time and for one place’ (Eliot). But if you want a solution that will perform long term under real world conditions, Go Slime! 

Does Slime Mold seem strange to you? Well, did you know, you were once slime? No, I’m not referring to our species’ evolutionary past. I’m talking about you! When you were in school, there were always a few kids who lived to study and weren’t satisfied with anything less than 100% on every test, right? 

Slime-like, tell me if I’m wrong, you estimated that you could test in the 85% to 90% range, good enough to satisfy the ‘rents’, and study only half as long…leaving more time for important things…like play. Plus your strategy gave you the flexibility to modify your schedule in special circumstances (e.g. final exam week).

“To Karen Alim, a theoretical physicist starting a postdoctoral project at Harvard University at the time… the flow of fluid can be a way of transmitting information…in Physarum, a creature that appears able to learn, remember and make decisions — all without a brain.

“Though Physarum is a single cell, the large body it forms can often be easily seen by the naked eye, growing to more than a foot in diameter under favorable conditions. It looks like a central blob from which a network of vein-like tubes emanates — larger tubes, then smaller tubes that fan out from them. Inside those tubes, cytoplasmic fluid is rhythmically flowing back and forth…

“Alim, who now works at the Technical University of Munich in Germany, figured out that encounters with food lead to an increase in local fluid flow within the tubes. This exerts greater shear force on the tube walls. The walls in that region grow thinner, allowing the tubes to expand.

“The opposite happens when Physarum encounters something awful like salt or light that it wants to get away from. In response to a repellent, the tube walls stiffen and contract, which redirects fluid flow elsewhere.

“More recently, Alim and colleagues discovered just what creates a tube network as efficient as Tokyo’s transport links. It ties into something crucial about the fluid flow in Physarum’s body: Tube walls respond to changes in flow with some delay. First the flow increases. Then, slightly later, the tube expands in response, causing the flow to decrease. This causes the tube to shrink, again with some delay.

“The result, Alim found, is that the best-positioned tubes will grow larger and larger and receive more and more flow, while others will fade away — and hence, over time, a super-efficient network of links will form.

“Put another way, Alim adds, you could say that the shape of the network (and its underlying fluid flow dynamics) helps Physarum to remember. Appropriately sizing its branches in accordance with food sources it has encountered recently makes for a simple but effective way to recall where food can be found…contraction patterns may persist and store information similar to the way waves of activity in our brain can store information.

“Slime molds can learn about each other: They are sensitive to aspects of each other’s behavior. They will approach others that have access to food, and avoid (burdening) ones that are starving or stressed…they also prefer to approach young individuals… But intriguingly, when they go through dormancy, or fuse with a younger individual, it’s as if they’re young again.” Perhaps we have a thing or two to learn from our slimy cousins!

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Giuseppe Arcimboldo’s Vertumnus (1591) portrays the Roman god of seasonal change as a human portrait composed entirely of fruits, vegetables, flowers, and leaves, symbolizing the unity between human identity and plant life. By constructing a recognizable human face from botanical elements, Arcimboldo expresses the idea that humans are formed from and sustained by nature’s cycles of growth and transformation. The painting also served as an allegorical portrait of Emperor Rudolf II, suggesting his power was aligned with natural order, abundance, and the forces that govern life itself.