'Bloodworms' harvest copper for metal jaws | Hacker News Reader

'Bloodworms' harvest copper for metal jaws

vice.com

69 pointselsewhen31 comments

Not metal, metal ions, unless "mineral...copper" means metallic copper. But the paper is only about the ionic copper. This is like saying your bones are metal because they're calcium phosphate and calcium is a metal. Neat animal (Glycera dibranchiata), lying clickbait headline, as you'd expect from Vice.

Paper link: https://www.cell.com/matter/fulltext/S2590-2385%2822%2900153...

PDF link: https://www.cell.com/action/showPdf?pii=S2590-2385%2822%2900...

"Extended PDF" link: https://www.cell.com/matter/pdfExtended/S2590-2385(22)00153-... (which appears to be the regular PDF plus 13 pages of supplementary information but for some reason is 5 times as large)

You are perfectly right.

As soon as I had seen the misleading title about "metal jaws", I was going to make the same comment.

Unfortunately, this kind of stupid title about "metal" body parts appears periodically in popular science publications, whenever the topic is about animals which use skeleton reinforcing minerals that happen to use manganese, iron, copper or zinc ions, instead of the (more commonly encountered in skeleton minerals) ions of calcium, silicon, strontium or barium.

There are a few bacteria which are able to reduce some metallic ions to the corresponding metal (e.g. silver ions to metallic silver), with the purpose of precipitating the metal ions from the water and thus avoiding the toxic effect of those metallic ions.

However, there are no known living beings, except humans, which are able to build useful structures using metals.

These charming 15" long worms with copper reinforced jaws are effectively in the Bronze Age. Soon they will transition to Iron, then they'll probably bypass the Industrial Age as too polluted (might as well learn from other's mistakes) and besides a coal fired worm is a pretty odd worm, and go full on nuclear. Worms with frikking lasers is what we will soon be contending with.

Oh actually they are far more interesting than that: "The worms turn their digestive system inside-out and launch an appendage, called an eversible proboscis, at their prey."

... and they are venomous.

So you approach your adversary. They turn around and drop their drawers and then it gets really weird. They extrude their entire large intestine through their arse and the end of it is sporting four metal fangs and dripping with poison.

How about an iron age snail? It lives near deep sea vents and uses iron minerals in its shell and scales on its foot. It also has symbiotic bacteria in its gut so it doesn't feed directly.

https://morethanadodo.com/2015/04/28/the-iron-snail/

Iron sulfide is an unrefined ore that humans could access well before the iron age (if or when they ever had a use for it). Fortunately for the birds (and fish with the ecological role of birds) of the world, there are no truly iron snails.

> Soon they will transition to Iron, then they'll probably bypass the Industrial Age as too polluted

But what about the Age of Snail?

At what point will the worms start the Internet and use phone apps for home delivery?

There’ll be a demand for 4G connections; that’s a YCombinator business opportunity waiting to happen, looking ahead to see future demand.

worm -> whorm-> whorm’st -> whormst’d

They will skip the industrial age, evolve fusion generators as stomachs, and be impervious to deep space. Launching themselves into the universe with large trebuchets and fusion fart themselves into orbit.

They'll live in the Gobi and Sahara as the size of whales as well. Their advanced biochemical processes will shape the ecosystem around them and spread the deserts further. A byproduct of their chemical processes will be a panacea for mental acuity and aging come to be know as melange. People will worship the giant worms and call them "the maker."

Actually this is not so.

The worms extrude their pharynx, i.e. the anterior part of their digestive tube, through their mouth and catch the prey, and then they pull the prey in their mouth, like some of the alien monsters from various SF movies (which were obviously inspired by such worms).

Catching a prey from behind does not seem to be of much use, because the prey would not be chasing the predator.

For a worm, which normally slides through narrow passages or which burrows in the sand, it is not easy to turn around with the rear end towards what was previously in front.

> Soon they will transition to Iron

Iron is strong, but not that hard and would wear away quickly. Tooth enamel is actually harder than steel and very wear resistant. Iron compounds like hematite are harder, but more brittle.

Iron is a pretty common element, I suspect if there was an iron compound better than calcium compounds for teeth we’d already have iron teeth.

Tooth enamel is not as hard as even unhardened steel. It's a composite material whose hard phase is hydroxyapatite, a hydroxyphosphate of calcium, which is even more brittle than hematite. But the hydroxyapatite crystals are below the critical size for flaw-insensitivity, and the protein matrix that binds them together is too soft to propagate cracks from one to the other. Limpets' teeth do use goethite, an oxyhydroxide of iron, in exactly the same way, achieving hardnesses that do exceed iron's.

So in a way we do already have iron teeth because there's an iron compound better than calcium compounds for teeth, if "we" includes mollusks.

"Iron is strong, but not that hard and would wear away quickly."

I was simply making a bit of a joke about progress. Why is the bronze age not called the copper age and why is the iron age not called the steel age?

"Tooth enamel is actually harder than steel and very wear resistant." Really? In which case I would like you to take a bite out of any RSJ you care to choose. That's a rolled steel joist which are not hardened but designed to work well as beams.

Material properties are quite tricky. Hard really means errr hard: a diamond is hard - it can scratch glass. Glass is hard, most steels can't scratch glass. Steel is generally not that hard but can be depending on the alloy (mixture with other elements/etc) Then there are the other material properties such as stiffness, ductility and elasticity and the rest.

Iron is generally brittle so if you make a sword out of just iron it will be quite stiff and look lovely until your opponent smacks it and it breaks. I can give you a load of steels with loads of different properties depending on what you need. The difference between iron on its own and steel is amazing. Pop in a bit of chromium and it resists rusting, for example. Steel is much more than just adding carbon.

Please don't bite any of them - they will destroy your teeth.

Bronze, iron, nuclear, spice

In case you want to see one of these things in action: https://www.youtube.com/watch?v=o7aM5gU8mFY

Got 2 seconds in and quit out. Big nope.

If you waited 15 seconds or so you could have seen it regurgitate some slimey green fluid!

That was my nope point. I did enjoy showing my child though!

One for the "Why do children dislike vegetables" list I bet science missed.

The spew really did look like pesto.

Thanks to your warning I made it out in a quick half a second. Still, that's half a second too long.

Now to scrub it from my watch history lest youtube get the idea I wanna see more.

I enjoyed it :) I gave it a thumbs up, so I'm sure I'll get more.

I was just interesting, the gross parts were only a few seconds at the begging and near the end, you should watch it.

Was about to show my wife but realized she's eating.

That guy sounds a lot like the Boston baby whale/sunfish guy.

And beavers have teeth reinforced with iron, which makes their front incisors a vivid orange: https://www.mcgill.ca/oss/article/did-you-know/beavers-have-...

The Xenomorph from the Alien’s franchise extracts iron from blood of its host. That is where it gets the metal for its teeth. Not explicitly stated in the films but something mentioned in one of the books.

Given that a human body contains about 3-5 grams of iron total, those teeth must be smaller than they look.

My extremely rough math suggests 282-470 people go into the making of those teeth, assuming xenomorph teeth are roughly 10x the volume of a human tooth (5-6 mL) and that they have thirty of them, no losses, and we're talking pure elemental iron and not a protein/metal matrix or otherwise. Figure 7.8 g/mL as the density of iron, by 6 mL per tooth is roughly 47g per tooth, so in the ballpark of 10-15 humans worth of iron per tooth. Humans have 32 teeth and 30 seems as good as any other number, so 47g/tooth by 30 teeth is 1410g of iron. That gives us somewhere between 282-470 people per set of xenomorph teeth.

I don't know where exactly I was going with this but it was fun to estimate.

They just eat tons and tons of people.

It’s almost as if the Aliens story universe is fictional, bruh.

But no tin. No bronze. Copper alone sucks. Meh.

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