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Comment by devindotcom | Hacker News Reader

I just wrote this up myself. The results are remarkable, but the credit seems entirely due to the spiders. Well, not entirely, but the data is so limited! They only got a handful of spiders, from the lab's back yard essentially, and a bunch of them died from nanomaterial exposure, malnutrition, or both after 1 trial!

Yet despite the bargain bin trappings, the results are so incredibly cool! The spiders just... incorporated carbon nanotubes and graphene into their silk-spinning process? What?! What's the mechanism?! No one knows! Who would have guessed this would work? It sounds like a joke experiment they cooked up while waiting for the glassware to bake!

Hopefully a more rigorous study replicating and expanding on these results will appear. But it just blew my mind the way this particular science appeared.

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A guess at the mechanism: the silk protein selection algorithm is an accept-first filter, the silk ducts being somewhat like human mammary glands. Anything the spider isn't specifically pulling back into its own blood as needed would then end up as an impurity in the webbing. (Easy experiment to do in its own right, but from a quick search I can't find evidence to support or refute it.)

Past that, the nanotubes just have to get locked into the matrix of the silk in the right orientation... which could just happen to anything of the right dimensionality in the silk as it anneals into shape.

> somewhat like human mammary glands.

This reminds me of a story of dolphins, who apparently suffer a lot from mercury poisoning, mostly caused by the smog of unfiltered coal plants entering their ecosystem. One issue of mercury poisoning is that the body has no way to get rid of it - it gets stored in the fats, IIRC. Unless you're a mammalian mom. Then the body gets rid of mercury through your milk. Mercury is most lethal at the infant age. So in short, most dolphin mothers' firstborns die [0].

Anyway, perhaps the carbon fibers are actually toxic, and the only way the spiders can get rid of the material is through their silk?

[0] http://www.takepart.com/article/2015/02/11/revealing-cove-do...

> Who would have guessed

Except for not being a dog, such a spider is anticipated in Goethe's little poem «Annonce» (Advertisement):

    A little dog is sought
    that never barked nor bit
    takes broken glass as feed
    leaves diamonds as - -

(my own translation, but wouldn't be surprised if it has appeared in these words before)

Yeah, pretty good!

    Ein Hündchen wird gesucht,
    Das weder murrt, noch beißt,
    Zerbrochene Gläser frißt
    Und Diamanten scheißt.

> Und Diamanten scheißt.

chuckles to self

This [1] is a pretty good description of the spider silk stucture. Turns out it's a self-assembled liquid crystal composed of oriented rods of a hydrophobic protein (an alanine/glycine co-polymer for those who care). It's not hard to imagine how a carbon nanotube could substitute for one of those if it's around in the soup...

[1] http://www.chm.bris.ac.uk/motm/spider/page3.htm

It seems this is how the most remarkable scientific discoveries happen, though -- purely by accident or as part of a wild trial "Hey, what if we just tried this...?"

This is fascinating stuff - now they just need to feed genetically modified spider-goats graphene and see what happens!

http://www.bbc.co.uk/news/science-environment-16554357

http://en.wikipedia.org/wiki/BioSteel

Nice discovery and thank you for sharing it. Concerning the article, there are a lot of superlatives which sometimes makes me wonder whether the author is overenthusiastic and still rational; Therefore a couple of comparions would be welcome for people who didn't study material resistance, e.g. "Such a web can hold a 2kg spade if it happens to hang in your garage". Can it?

I agree, so I asked my material scientist friend. Based on the strand thickness in that microscope image being approximately 8 microns, a single strand can hold about 250g. So a web would probably hold a spade, depending on how well it sticks. Incidentally, if you need a material scientist, OracleCarbon hangs out in IRC in #xkcd on the Foonetic network and is happy to answer stuff like that.

I was actually joking when I thought of a spade, I'm impressed!

Is there a word like serendipity that means "found as a joke" instead of "found by a fortunate accident?"

Not a single word, but http://catb.org/jargon/html/H/ha-ha-only-serious.html is related.

Not a word, per se, but this mechanism of discovery tends to correlate with being the sort of thing that wins an Ig Nobel prize.

> Who would have guessed this would work?

A lot of people? The carbon has to end up somewhere. I don't see this as surprising at all, any more than it's surprising that if you, a human, eat a lot of arsenic, you'll add some of it to your hair. Growing hair and growing silk are not fundamentally different activities.

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