Slime mold is an extremely interesting species that can perform computation, even without a nerve system.
> Ateam of Japanese and Hungarian researchers have shown P. polycephalum can solve the Shortest Path Problem. When grown in a maze with oatmeal at two spots, P. polycephalum retracts from everywhere in the maze, except the shortest route connecting the two food sources.
> When presented with more than two food sources, P. polycephalum apparently solves a more complicated transportation problem. With more than two sources, the amoeba also produces efficient networks. In a 2010 paper, oatflakes were dispersed to represent Tokyo and 36 surrounding towns. P. polycephalum created a network similar to the existing train system, and "with comparable efficiency, fault tolerance, and cost". Similar results have been shown based on road networks in the United Kingdom and the Iberian peninsula (i.e., Spain and Portugal). Some researchers claim that P. polycephalum is even able to solve the NP-hard Steiner Minimum Tree Problem.
> As the slime mould does not have any nervous system that could explain these intelligent behaviours, there has been considerable interdisciplinary interest in understanding the rules that govern its behaviour. Scientists are trying to model the slime mold using a number of simple, distributed rules. For example, P. polycephalum has been modeled as a set of differential equations inspired by electrical networks. This model can be shown to be able to compute shortest paths. A very similar model can be shown to solve the Steiner tree problem. However, currently these models do not make sense biologically, as they for example assume energy conservation inside the slime mould. Living organisms consume food, so energy can not be conserved. To build more realistic models, more data about the slime mould's network construction needs to be gathered.
[...]
> Moreover, it has been reported that plasmodia can be made to form logic gates, enabling the construction of biological computers. In particular, plasmodia placed at entrances to special geometrically shaped mazes would emerge at exits of the maze that were consistent with truth tables for certain primitive logic connectives. However, as these constructions are based on theoretical models of the slime mould, in practice these results do not scale to allow for actual computation. When the primitive logic gates are connected to form more complex functions, the plasmodium ceased to produce results consistent with the expected truth tables.
Shortest Path Algorithm has well known heuristics. If all you want is "close enough" then sure, you can compute quickly. But when that route corresponds to how much you spend on fuel to complete your route, usually you want to use something better than "good enough".
This, as with Soap Bubble computation, only really shows it can reach local minima, not global minima, which is really what most people care about.
That doesn't make it any better. We know the blob is a slime mold and slime holds are protists. They're weird and mysterious, sure, but the article makes it sound like this is a completely new and unnamed discovery. They're very careful to avoid the words 'slime mold' and 'protist', which really should be in there.
That's my point. An article would explain why the claims hold true and summarize what is actually known about the organism. What's linked is a couple of paragraphs that seems to regurgitate some copy from elsewhere. It isn't reporting, and it is isn't an article, where they present a story of interest.
It's just a press release for the museum, seemingly copied, and ought to be identified as such.
Slime mold is interesting. There's one species that, if you assemble food sources in the population densities found in Tokyo, will grow to look very similar to the Tokyo subway system:
There are causal paths from population density to subway layout and from subway layout to population density, but one of those paths is significantly more responsive than the other. Population density constantly adjusts to local circumstances such as transit access; subway layout adjusts in very expensive bursts. A subway tunnel once built is not going to move 30 meters to the left even if that would obviously be a better location.
So it seems pretty likely to me that the population density of Tokyo is more a result than a cause of Tokyo's subway layout. This is backwards from the slime mold experiment, where the layout is caused by the resource density.
Interesting thought that I had not considered. But I'm also not sure I share your belief that the population density is more a result than a cause. The whole fact that adjusting the subway is very expensive suggests to me that there needs to be a population worth serving prior to construction. Seems like a bit of a chicken/egg problem, would be interesting to see some population stats pre/post subway construction.
I wonder if this has potential for solving practical optimization problems. Why glue together some ML model when you already have a premade solution with millions of years of training time by mother nature
Reminds me of "Doctor Diagoras", a short story by Stanislaw Lem. Also known for the "Solaris" novel (adapted by Tarkovsky and Soderbergh)
We expect to find alien lifeforms out there, but plenty of species on Earth remain to be discovered and studied. And rediscovered: finding out we overlooked some particularly interesting/puzzling behavior in apparently boring species, whose research might lead to breakthroughs in genetics, computing, mathematics, etc.
> Fungi, by contrast, keep it casual. To mate, all a fungus has to do is bump up against another member of its species and let their cells fuse together. S. commune uses a special kind of structure called a clamp connection to do this, and it allows them to exchange their cell’s nuclei, along with the genetic information inside. This keeps reproduction simple and means that a potentially huge number of sexes is possible — other fungi species have dozens or more, though S. commune is certainly an outlier.
> The “sexes” don’t really involve physical differences either, as we might think of when the word “sex” comes to mind. The variations are all in the genome, at two separate loci, or locations, each of which has two alleles, or alternate forms. The loci are called A and B and the alleles are termed “alpha” and “beta.” That makes four possible sexes, but there’s another twist. Every A-alpha/beta and B-alpha/beta can have many different variants, called specificities. It amounts to more than 339 specificities for A and 64 for B. Putting those two together yields thousands of possible unique sexes.
> The fungus can mate with any specificity as long as it’s different somewhere on both A and B. So, two prospective mates could both have the same A-beta and B-alpha, but have different A-alphas and B-betas and they’d be fine to hook up. If they shared A-alpha and A-beta, though, their pheromones wouldn’t be compatible, meaning that they couldn’t carry out the reproductive process. That leaves a ton of options for mating, though, and essentially means that anyone a fungus meets is fair game for sexy time.
But are those real sexes? They do apparently have some sort of impact on reproduction, but the only limitation seems to be that they can't mate with someone who has the exact same structure of the these alleles.
Which makes me wonder if this might have developed not so much as a way to help reproduction, but as a guard against inbreeding.
Yes. Sexes aren't defined as being based on different chromosomes or having different physical anatomy (there are more mainstream examples of outliers for both of these). It's just a classification system for reproduction limitations.
> Audrey Dussutour and David Vogel had already trained slime molds to move past repellent but harmless substances (e.g. coffee, quinine, or salt) to reach their food. They now reveal that a slime mold that has learned to ignore salt can transmit this acquired behavior to another simply by fusing with it.
> To achieve this, the researchers taught more than 2,000 slime molds that salt posed no threat. In order to reach their food, these slime molds had to cross a bridge covered with salt. This experience made them habituated slime molds. Meanwhile, another 2,000 slime molds had to cross a bridge bare of any substance. They made up the group of naive slime molds.
> After this training period, the scientists grouped slime molds into habituated, naive, and mixed pairs. Paired slime molds fused together where they came into contact.
> The new, fused slime molds then had to cross salt-covered bridges.
> To the researchers' surprise, the mixed slime molds moved just as fast as habituated pairs, and much faster than naive ones, suggesting that knowledge of the harmless nature of salt had been shared.
> This held true for slime molds formed from 3 or 4 individuals. No matter how many fused, only 1 habituated slime mold was needed to transfer the information.
> To check that transfer had indeed taken place, the scientists separated the slime molds 1 hour and 3 hours after fusion and repeated the bridge experiment. Only naive slime molds that had been fused with habituated slime molds for 3 hours ignored the salt; all others were repulsed by it.
> This was proof of learning.
> When viewing the slime molds through a microscope, the scientists noticed that, after 3 hours, a vein formed at the point of fusion. This vein is undoubtedly the channel through which information is shared.
I think the number of questions like this is indicative that the article is just click bait. Go read about slime mold on wikipedia, and forget everything you read here.
If we talk about similarities to animals it should be mentioned that slime molds actively move.
"In nature, slime moulds actively move around searching for bacteria or fungi, which they subsequently engulf. Slime moulds can achieve speeds up to 5 cm/h" [1]
It probably has no sex at all, and is some king of hemaphrodite orgnanism or something that just reproduces with something more simple like parthenogenesis?
tl;dr: There are 720 variations of the animal that have different sexual reproduction limitations with each other. They have the same anatomy but differ on the DNA level.
No. It's just a small part of the DNA (like male vs female in most animals). The organism that can't reproduce with another organism still came from two of the same organisms.
When did Reuters get so sensationalistic? I remember years ago when they were the matter-of-fact news agency that other journalists got their info from and built their sensational articles around.
From TFA:
> This newest exhibit of the Paris Zoological Park, which goes on display to the public on Saturday, has no mouth, no stomach, no eyes, yet it can detect food and digest it.
> The blob also has almost 720 sexes, can move without legs or wings and heals itself in two minutes if cut in half.
Yeah, it's a slime mo(u)ld, we get it. You don't need to get all carnie shouter about it.
Back to my original question, when did Reuters decide their strategic shift into their own souped-up content?
Reuters has a 'policy' of neutrality, but they're a for-profit org, and the news started getting more skewed after Thompson bought them. Even before they got all click-baitey, they used to suppress climate change news and feature outright quack climate change deniers. Before they got bought out, the news was just a side product to their market data product.
AP is the one that is a straight newswire service, that provides story stubs and fact outlines from around the world, which other journalists then sensationalize.
All that being said... This article didn't seem all that sensational. Would you have preferred "Paris Zoological Park Showcases Slime Mould Exhibit"?
> Ateam of Japanese and Hungarian researchers have shown P. polycephalum can solve the Shortest Path Problem. When grown in a maze with oatmeal at two spots, P. polycephalum retracts from everywhere in the maze, except the shortest route connecting the two food sources.
> When presented with more than two food sources, P. polycephalum apparently solves a more complicated transportation problem. With more than two sources, the amoeba also produces efficient networks. In a 2010 paper, oatflakes were dispersed to represent Tokyo and 36 surrounding towns. P. polycephalum created a network similar to the existing train system, and "with comparable efficiency, fault tolerance, and cost". Similar results have been shown based on road networks in the United Kingdom and the Iberian peninsula (i.e., Spain and Portugal). Some researchers claim that P. polycephalum is even able to solve the NP-hard Steiner Minimum Tree Problem.
> As the slime mould does not have any nervous system that could explain these intelligent behaviours, there has been considerable interdisciplinary interest in understanding the rules that govern its behaviour. Scientists are trying to model the slime mold using a number of simple, distributed rules. For example, P. polycephalum has been modeled as a set of differential equations inspired by electrical networks. This model can be shown to be able to compute shortest paths. A very similar model can be shown to solve the Steiner tree problem. However, currently these models do not make sense biologically, as they for example assume energy conservation inside the slime mould. Living organisms consume food, so energy can not be conserved. To build more realistic models, more data about the slime mould's network construction needs to be gathered.
[...]
> Moreover, it has been reported that plasmodia can be made to form logic gates, enabling the construction of biological computers. In particular, plasmodia placed at entrances to special geometrically shaped mazes would emerge at exits of the maze that were consistent with truth tables for certain primitive logic connectives. However, as these constructions are based on theoretical models of the slime mould, in practice these results do not scale to allow for actual computation. When the primitive logic gates are connected to form more complex functions, the plasmodium ceased to produce results consistent with the expected truth tables.