Namibian fairy circle debate rages on: Sand termites or Turing mechanism? | Hacker News Reader

Namibian fairy circle debate rages on: Sand termites or Turing mechanism?

arstechnica.com

94 pointsthunderbong42 comments

Turing "mechanism" is a bit misleading, but I'm fascinated to learn about Turing patterns. [0] I'm not swayed by either side of the debate (and don't really care), but learning about Turing patterns was worth the read.

[0] https://www.chemistryworld.com/features/turing-patterns/4991...

I was pretty confused here. The article should have explained the meaning of Turing patterns sooner. It's a much drier (heh) article than expected without the premise of unconscious biological systems performing computations in sand.

Wired has a good introductory article about them from more than a decade ago. https://www.wired.com/2011/02/turing-patterns/

How is it misleading?

Turing mechanism sounds a lot closer to Turing machine than a chemical process discovered by Turing which does not have the word mechanism in its name.

Clickbait will continue to escalate until it's outright lies and everything is a tabloid.

Checking the first 30 or so results from a google search for "Turing mechanism" every single one is about Turing patterns and the mechanisms that produce them, and not one refers to Turing machines or any other aspect of Turing's computer science work.

Many people don't know Turing did other things. Doesn't make it clickbait.

The Australian native tribes who have lived among their Fairy Circles for at least 50,000 years, seem to be on the termite side of the argument.

https://theconversation.com/first-peoples-knowledge-of-myste...

They probably are right.

It is mind boggling the time period over which tribal knowledge develops.

Antiquity can't be substitute of truth. Granted many of these claims may have strong correlations but I also hear a lot of nonsense that is as old as the civilization itself. Witchcraft is only one of them.

You mean the sun isn't really a god riding in a chariot pulled by horses of fire? But it's been told for all of history, it surely must be truth

Not if you read the actual link above.

The 50,000 year deep indigenous knowledge being discussed there isn't magical sky friends, it's deep ecological knowledge about plants, animals, and where to find food and water where no outsiders would think to look.

Exactly. Such as how the aboriginal Australians know how to do controlled burns to keep megafires from happening. The government is starting to listen to them on how to do that.

At least the sun does really exist

the story of the sun being a chariot driven by a god (i.e. a humanoid) must have been a story which encoded useful information, perhaps things like "every morning, get up and do your job" and "here's what happens when you show fiery temperment", etc.

you can't convincingly tell the scientific story of the advantages of adaptive evolution without realizing that stories told over and over again must have been adaptions, they're too much of a waste otherwise. We like listening to stories. Why? you said it best.

>it surely must be truth

Himba bushmen

It's rare to see an error in the opening sentence of an article, and maybe a nitpick but I believe "bushmen" usually refers to San hunter-gatherer nomads, not Bantu language-speaking pastoralists.

Unless “bushmen” is being used in some generic “people who live out in the bush” sense? That stuck out to me too.

(I’m very closely connected to one of the foremost Western experts on the Himba and have spent time with them myself. Definitely not the same as the Bushmen.)

> I’m very closely connected to one of the foremost Western experts on the Himba and have spent time with them myself

This is such a strange sentence that makes it sound like they're some exotic, uncontacted people. Give it a couple of hours until its waking hours in Namibia, and we're going to have Himba people in this thread.

I’m not really sure what you mean. There are Himba people on the internet, of course. But there just aren’t that many of them in the world period, and there aren’t exactly a ton of non-Namibians who know any.

And I thought it was implied, but I was talking about Himba people who live traditionally, which sort falls under the “out in the bush” heading. Not too many of them hanging out on HN.

San is a derogatory word to describe them. In general it refers to several language groups that extend all the way from South Africa to Namibia and Botswana.

So is bushmen. Which does attempt to refer to the San people. It is also considered rude.

It depends on how it is used though. The San council in SA is ok with it’s use in positive contexts.

They have other names by which they refer to themselves.like !Kung. These represent their individual nations.

Himbas don’t have the same language or history as San/Bushmen. Also Himbas raise cattle .. So you are correct that the term “Himba bushmen” is very off. (Although I’m not familiar with Himba’s preferred names)

It’s a very western / German thing to talk like this with out knowing the full context and just assuming “hey they live in the bush lol bushmen”

Slightly off topic, but in the UK we call rings of fungus "fairy rings" (https://en.wikipedia.org/wiki/Fairy_ring).

Myself and others have witnessed these at native orchid sites and one pattern is that orchids don't grow within the ring; it seems the expanding ring consumes nutrients within, eating outwardly as it expands. This in itself is interesting because typically terrestrial orchids have a heavy symbiotic relationship with fungi. There are interesting physical similarities I can see here; a robustness on the perimeter due to higher nitrogen availability, and more barrenness within the interior.

I see these in the forests around where I live quite often in the autumn. In Norwegian they're called "heksering", translates to witch ring, and have historically been thought of as a bad omen. Specifically a remnant of gathering places for witches, hence the name.

The species in this case is Leucopaxillus giganteus, which is edible, and due to the unique fairy rings, unusually easy to identify. Though I still don't dare try them because only young specimens are edible and mature ones are known to contain KCN...

This isn't mentioned in the article (or I hope I didn't miss it) but did they try to dig into the patches to check if there are termites or not? They said they measured moisture at different levels beneath the surface, but that can be done without actually digging.

Right? Isn't it super simple to see if there are termites there? I was lost about that.

The argument from the article is that the fairy circles live longer thank the termite colonies persist, so you’ll always only see termites at some of them (both sides agree termites are sometimes but not always found).

The article says that the damage to the grass roots is hard to discern and requires magnification. Also, the termites apparently are hard to observe but have been found

Not quite on the scale of the Great Debate of 1920 https://en.wikipedia.org/wiki/Great_Debate_(astronomy) settled by Hubble in 1925 ... but still amusing!

Several paragraphs in, and I am waiting for the explanation how the aliens are testing us if we are intelligent. Bit of a let down, but I do want to know how I can get a job studying sand circles. Think of the stress, or lack thereof.

No, this is the result of the tractor beams when the collect earth samples. It's not actually intended as a test in that manner. That's just a bonus

If you're thinking of the stress: There are exceedingly few positions open for studying sand circles, and probably not much money for it.

impressively attention-grabbing headline aside, could they not both the true? a Turing mechanism where termites are the "activator chemical"

But then what's the inhibitor? Termites and water scarcity would be on the same side of the equation, no?

Sometime around 2002 I chartered a small plane to photograph the landscapes around the bunch grass prairies in NE Oregon. These are one of the last remaining ecological intact bunchgrass prairies in North America.

One of the features I caught on film are “mima mounds”. To this day I license these images over and over again because the mechanism that shapes the mounds is hotly debated. I had no idea what they were at the time, but it is fascinating.

It’s also fascinating that conversations and debates around these kinds of mysterious features just keeps on going.

Oh interesting - in Australia the current go to theory is Hydrogen leakage.

> it was plant water stress that caused grasses to die inside the bare patch of fairy circles

This seems like the simplest explanation, especially with desert plants with high water efficiency. I’d think that would give groups of such plants a higher ‘surface tension’ leading to a more defined, circular boundary.

I don't see why circles would necessarily be the most parsimonious shape of it was indeed water scarcity (then again im not sure termite colonies or home ranges are necessarily circular either)

I’m confused why it can’t be a combination of the two? Termite damage and colony over growth and collapse combined with water damage over taking the plants in colony zones

I'll stick with the underground toxic dragon hypothesis.

By Turing mechanism they likely refer to reaction-diffusion systems (also pioneered by Turing), rather than his better known Blade Runner material

not obvious to me from the ars article, but the circles are

> 2 and 12 metres (7 and 39 ft) in diameter

according to WP

I'd think that marking off a square maybe 5-10 meters on a side and dumping pesticides onto it for a year, would answer the question. If they still form inside the square, it's probably not due to insects.

That's a brave stance to take on this forum. Leeching isn't a problem in dry earth is it? Sounds like a perfectly rational thing to do. Maybe dump a bunch of PFAS in that square, or an entirely different square, you know, for science.

Since we're just suggesting whack science, let's get soil from the Bermuda Triangle and replace it with the fairy circles to see if they are spawn points.

Reply on news.ycombinator.com