Mega-Tunnels Dug by South American Megafauna (2017) | Hacker News Reader

Mega-Tunnels Dug by South American Megafauna (2017)

blogs.discovermagazine.com

145 pointsvezycash71 comments

>Dating the burrows also remains guesswork at best—animals don’t dig holes after they go extinct. However, they had to have been dug at least 8,000 to 10,000 years ago, when South America’s giant ground sloths and armadillos vanished.

Or, when humans came on the scene and 'vanished' them.

If only early man had worried about zoological diversity and the morality of eating giant sloth meat.

It probably had more to do with viewing them as a threat (which they were) than as food.

Whether they viewed them as a threat or food, modern humans (i.e. humans with fully developed hunting skills and weapons) who encountered megafauna that weren't afraid of them frequently slaughtered them to the point of extinction.

Bet they were tasty.

A more detailed description is included in this publication from the author credited for the first photo:

http://www.ufrgs.br/paleotocas/Frank_et_al_2012.pdf

I'll take this opportunity to advertise one of my favourite science podcasts, Fronteiras da Ciência:

http://www.ufrgs.br/frontdaciencia/

It is in portuguese, but one of the older episodes from season 5 is a very fun and informative interview with prof Heinrich about these burrows.

Thanks for the recommendation! Added to my player

elon musk needs to hire some of these paleoburrows to finish his jobs - but seriously this is so interesting.

does anyone know if anyone has casually mapped these out? it would be scary to explore these, I imagine all types of animals / bears (maybe not as much in South america) use these caves as their homes.

Funny how the article entirely ignores huge caves on Africa dug by elephants mining salt.

They ate the tailings.

Maybe there is only one such cave known, so somehow it doesn't count?

I don't know why, but this feels a lot more scarey than seeing dinosaur footprints. Definitely makes me feel more like "prey".

Homo sapiens is technically part of the megafauna, so the human miners that most probably dug this tunnels looking for valuable raw matherials would fit in this description, yes.

Do you for some reason not believe the experts in the article? Or have an explanation for the claw marks?

I'm not believing it because. 1) I'm not afraid of the experts. 2) They obviously are wrong in this case, as you can see if you take a look to the photos. 3) Yes, I have a better explanation for the marks. One that does not involve magical tetrapods digging in narrow spaces with unlimited degrees of rotation in the shoulder.

An expert is somebody that has done any possible mistake in a field. They commit mistakes all the time. This is just part of the journey and nothing to be ashamed of.

"They obviously are wrong in this case, as you can see if you take a look to the photos."

I believe they might be wrong too, but using the term "obviously" based on a look to the photos of an article is just arrogant. No matter if you are right in the future about they being wrong.

"X looks like Y, thus, it must be made by Y" - that's the kind of inane logic I see on so many YouTube conspiracy videos. It's absurd to assume that just because something looks like something to a layperson, an expert would see them in the same way.

Not to mention that this line of logic has been used by everything from conspiracy nuts to eugenicists

And also the original article.

So you're saying that you know for a fact that Amilcar Adamy, a geologist with the Brazilian Geological Survey (known by its Portuguese acronym, CPRM), is actually a layperson? What evidence do you have that he was lying about his qualifications and actually is a layperson who has no idea what he's talking about?

Are you an expert in spotting fraudulent researchers who lie about their qualifications in multiple magazine articles and peer reviewed scientific publications?

What are your own qualifications in that field, and can you prove your accusations? Or are you doing exactly what you're baselessly accusing someone else of doing, without any evidence? Do you have an instinct for debunking fake science?

Is his biography and all these research papers and articles he's published fake too? If it's not true, somebody sure went to quite a lot of effort to perpetrate this fraud... What do you think their motivations were? Perhaps you should report him?

https://www.escavador.com/sobre/2015231/amilcar-adamy

https://www.linkedin.com/in/amilcar-adamy-90b71b25/?original...

https://nl.pinterest.com/gsarisoy/

https://www.natureworldnews.com/articles/36983/20170403/myst...

https://www.beyondsciencetv.com/2017/07/05/hundreds-of-giant...

http://www.look4ward.co.uk/animals/giant-tunnels-in-south-am...

https://www.iflscience.com/plants-and-animals/extinct-megafa...

He literally says, "Although the exact identity of the producers of the burrows is yet unknown, the dimensions and morphology point to ground sloths and giant armadillos." https://www.tandfonline.com/doi/full/10.1080/10420940.2016.1... That is exactly "Looks like Y, must be made by Y."

I'm not saying it's a bad heuristic. It's fine for coming up with ideas. But they apparently haven't yet found bones or fossilized poop or other signs of habitation by giant fauna.

> I'm not saying it's a bad heuristic. It's fine for coming up with ideas. But they apparently haven't yet found bones or fossilized poop or other signs of habitation by giant fauna.

Technically, finding that where you'd expect to find it were they the diggers is still “Looks like Y, must be Y”.

Fundamentally, that's the only way to draw conclusions about a process you aren't directly observing.

Heck, even conclusions from direct observation are quite literally “Looks like Y, must be Y”.

And that makes him not an expert but actually a layperson and an incompetent liar about his credentials how? Did you directly observe that he's lying about his expertise? Can you refer me to someone more qualified, with a time machine, who directly observed what happened millions of years ago, and disagrees with him?

Which is pretty much just a travel report so it doesn't wield much authority.

I've also come to learn that many things that seem obvious to a layperson often turn out to be false. So just because something seems obvious to somebody or common sense seems to suggest something or their gut instinct says so, really doesn't make it true.

I sometimes wonder what is the evolutionary advantage of being as sure about ourselves and dismissive of others like a lot of us humans are.

Reminds me of the quote by Charles Bukowski "The problem with the world is that the intelligent people are full of doubts, while the stupid ones are full of confidence. "

This phenomenon seems to be explained by the Dunning–Kruger effect.

The best lack all conviction, while the worst

Are full of passionate intensity.

- W.B. Yeats, The Second Coming

https://www.poets.org/poetsorg/poem/second-coming

You seem rather confident with that assertion But I doubt you were serious!! baddum-ts

For anybody that is wondering what baddum-ts means, here it is:

https://www.youtube.com/watch?v=VDAlblogUmY

Making a decision, and sticking to it, even after hardship, is what makes us human. How we leverage it is the art. Notice you always read "Confidince is sexy" and "Leading isnt about being right or wrong, but making choices, and being accountable to them". These are sides of the same coin. Heroics, hubris, same root.

The ability to learn is what makes us human. Otherwise we'd be idiots incapable of ever improving.

Percicely. Without making hypothesis and working on possibly wrong grounds, we cannot test our beliefs and move forward. I am not suggesting that resolve supercede observation.

> Heroics, hubris, same root

What comes up must come down - wer hoch fliegt, fällt tief (who flies high falls deep)

It gives us a bias to action. Ultimately, our brain's job is to make our muscles do stuff to keep our body alive and reproducing. A brain so paralyzed by self-doubt and indecision that it never takes action wouldn't last too long.

Sometimes they're right and cause a huge change in how we think about the world and science and shit. Sometimes.

Hubris protects us from the self-damage incurred by reflection.

> Yes, I have a better explanation for the marks. One that does not involve magical tetrapods digging in narrow spaces with unlimited degrees of rotation in the shoulder.

Truly, please provide it to me. I hope you've come up with something that doesn't lead to an alternative history where it's the Aztecs colonising Spain.

> please provide it to me

Of course I'll do. By third time: hu-man mi-ners

Is there something comparative, perhaps based on the width, depth, texture, or curve of the marks, that your expertise in this field leads you to conclude that these are, incontrovertibly, tool marks rather than claw marks?

Or you just going by "gut feeling" and don't have any actual proof?

I mean, we all know that our Aztec oppressors had iron pickaxes in 10000BC.

I mean, you punch a couple of trees and you can make a pickaxe with just wood easy-peasy. You can’t mine ores with it but it will get you through stone at least.

Please back up your claims with evidence.

That doesn't sound like an explanations for the marks. I even gave you a hint why.

You sound Ferengi. Is your universal translator broken?

https://www.youtube.com/watch?v=_w7JrSPc5WY

I'm all for questioning new science that hasn't been thoroughly proven, but to say it's obvious is pretty arrogant.

I didn't know KenM browsed Hacker News.

I would bet it was the work of humans also. There are claw marks, but it seems like very few. Isn't it possible that a clawed creature found this hole and lived in it at some point?

The presence and absesce of claw marks has to do with the type of rock (iirc, the claw marks appear in the clay tunnels)

>There are claw marks

Undistinguisable from modern pick axe marks, and with a similar angle and pressure than an human worker would apply. A much stronger animal wouldn't make such uniform and shallow marks in clay.

Not all the marks in a prehistoric cave are necessarily prehistoric.

> Undistinguisable from modern pick axe marks, and with a similar angle and pressure than an human worker would apply. A much stronger animal wouldn't make such uniform and shallow marks in clay.

What a load of B.S.

Have you ever done any significant manual excavation with a pickaxe and shovel?

No human is going to be leaving such long and deep scars in clay with a pickaxe. The progress is much slower for mere humans, clay is an awful material to dig through.

For a massive clawed animal however clay would not be such a challenge to leave such long uniform scars. Sure the pattern resembles what one might imagine a pickaxe leaving, but humans lack the force to drive a pickaxe in that fashion through clay.

> No human is going to be leaving such long and deep scars in clay with a pickaxe

> clay is an awful material to dig through.

> humans lack the force to drive a pickaxe in that fashion through clay.

All wrong. Digging in granite would be "awful". Digging in clay... Meh. I do it all the time. I have meet a lot of humans able to dig a hole into clay in fact, so I'm not the only one.

If you find shovels "intimidating" maybe you should try it more. Even small children are able to play with it.

One thing is clear: you have lots of experience in _burrowing_.

> What a load of B.S. Have you ever done any significant manual excavation with a pickaxe and shovel?

(rolleyes) Yes. I have a shovel and I'm not afraid to use it.

Congratulations, shovels can be intimidating to use as far as hand tools go. Certainly more so than a pickaxe.

They don't look like pickaxe marks at all to me. They aren't as uniform or straight, they aren't all going in the same direction and they don't have uniform depths.

https://perstoremyr.files.wordpress.com/2012/01/krauchthal_8...

http://blogs.discovermagazine.com/crux/files/2017/03/paleobu...

The marks in the first photo are done by a stone chisel (or something similar), not the kind of marks that a pick axe would make normally. Very different tools with different purposes.

But I see where you are going.

https://per-storemyr.net/2013/01/22/stone-extraction-with-pi...

The fact that a pick axe can be used like a chisel does not mean that it couldn't produce other types of marks also.

> I'm not afraid of the experts

Eh kills experts and doesnt afraid of anything

> I'm not afraid of the experts.

What?

We might be being trolled by Trump.

Sounds like you have a natural instinct for science.

What valuable raw materials would those be? I'm assuming you can deduce this from just the photos as well.

> What valuable raw materials would those be? I'm assuming you can deduce this from just the photos as well.

I can think in several reasonable possibilities to check for. I'm assuming that you are able also.

I will not enter in that "If you are so gooood, show me that you know all" game. Lets focus in the facts of the problem, not in me, or in my "arrogance".

Maybe I misunderstood, your premise is that these were dug by humans looking for valuable materials but you are not willing to engage in the "here's evidence to support my claim" game?

That's not a good way to ever be taken seriously but I guess you can tell that already.

> What raw materials whould those be?

My first guess where pure clay and maybe salt. After reading the article and seeing the "comb pattern" linked with a source of water, and the "seats" and the "reinforcement arcs" and the forked tunnels I would add also to this list some precious or semiprecious stones of aluvial origin filtered from the mud (would explain also the rounded section of some but not all parts of the mine).

There is not need of an iron pick to dig in clay. It helps, but all you need is a wood stick with a fire-hardened point.

More reasons for a nonhanthopogenic explanation:

Some of the smaller burrows (dug by armadillos) are too small to fit a human.

These kind of burrows are only found in south america.

There is no evidence of human presence (wall paintings, fireplace remains, etc). Except in some cases and even then only at the very entrance (suggesting that people found these later but never ventured in the dark parts)

There is evidence of claw marks on the walls, but no evidence of human tool use (pick axes, etc)

Some of the burrows are dug in sandstone.

> Some of the smaller burrows (dug by armadillos) are too small to fit a human.

How much small?. Children worked in mines also

>These kind of burrows are only found in south america.

Attribuable to local cultural differences. You can find mohais only in Rapa-nui.

> There is no evidence of human presence (wall paintings, fireplace remains, etc). Except in some cases...

The article talks about modern graffitis and marks of modern tools.

> and even then only at the very entrance (suggesting that people found these later but never ventured in the dark parts)

You can't make a fire in a semi-flooded area. And they probably wouldn't make a fire close to clay if their purpose is to dig in the clay looking for precious stones that can be distroyed by fire. Softer is better.

> There is evidence of claw marks on the walls

This is circular reasoning. There is evidence of marks on the walls and we don't know who did it or how they were created.

> but no evidence of human tool use (pick axes, etc)

Neither is evidence of sloth bones or broken claws or fosilised faeces or dead animals. Absence of evidence is not evidence of absence.

Maybe we are not looking in the right place.

> Some of the burrows are dug in sandstone.

Keratin is softer than sandstone and a soft material will not scratch a harder material. This is evidence against non-anthropogenic theory unless you add teeth to the equation (but sloths and armadillos belong to the order edentata, that means "toothless"). They do not have strong renewable frontal teeth like rodents have

The pattern of "successive digging" suggests that these burrows were dug over a long period of time, by animais larger than humans

that makes sense - I could see it almost as a daily task, families hunt for food, graze, and spend a few hours digging then sleep. really interesting stuff

Ah the good ol' HN smackdown on blatant arrogance. Experienced it many times myself and love seeing it, good job community, keeps us honest!! :)

Groupthink is a feature not a bug?

If you're insinuating that HN suffers from group think, I assure you if you spend some time going through the comments you'll find many healthy spirited debates. There's nothing inherently wrong with the OP, it's about how it was said, not what was said. From what I've seen, HN tries to be a friendly yet intellectually challenging place, and I personally really appreciate that spirit.

On Reddit it is. The jury is still out on HN.

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