Mantis shrimp ‘fist’ could inspire new body armour
Published: 17 July 2012 (GMT+10)
This is the pre-publication version which was subsequently revised to appear in Creation 36(4):40–41.
Credit: Jenny, Wikipedia.org
The mantis shrimp (aka stomatopod), has one of the strongest ‘punches’ in nature. A specimen only an inch (2.5 cm) long can draw blood if they hit a human finger, and bigger ones have caused severe injuries. Considering how some can grow a foot (30 cm) long, and one has even reached 15 inches (38 cm) long, they are not to be messed with! 13
With an intricate catapult mechanism, its ‘fist’ (called a dactyl) can accelerate up to 10,600 g1 (a greater acceleration than a 22-calibre bullet—while underwater—and hundreds of times what humans can stand2), high enough to induce a mini-explosion called cavitation.3 If kept in captivity, this punch can shatter the glass walls of their tanks. And in the wild, it breaks the shells of its prey, which are often marvels of engineering toughness in their own right.4
We also noted its amazing colour vision, with 12 primary colours receptors—four times as many as humans.5 Later we noted how DVD makers wanted to copy the shrimp eye’s ability to change the polarization over multiple colours.6
There are actually three different regions of the club that cooperate ‘to create a structure tougher than many engineered ceramics.’
But back to its powerful punch: it raises the question of how the ‘fist’ itself can survive. We noted that it moults frequently to regenerate. But frequent moulting could not be the whole story. It could not be frequent enough to withstand 50,000 high-speed strikes against hard prey shells in its lifetime.
Recently, a research team at the University of California, Riverside’s Bourns College of Engineering, discovered what makes its club so damage-resistant.7
There are actually three different regions of the club that cooperate “to create a structure tougher than many engineered ceramics.”8
The outer region that actually contacts the prey is mineral rich, like our bones. But this intrinsically brittle material is buttressed by the next layer, comprising “highly organized and rotated layers of chitin … fibers dispersed in mineral”. (Chitin is a complex polymer, i.e. made from smaller molecules joined together, in this case modified sugars. It is the main component of the outer “skeleton” of many invertebrates, and we have used it to make a strong biodegradable material called “shrilk”.9) In the mantis shrimp club, the arrangement of its tough chitin fibres enables them to absorb the energy of stress waves from the impacts. And the third region comprises “oriented chitin fibers, which wrap around the club,” which holds it together.
This club is stiff, yet it’s light-weight and tough, making it incredibly impact tolerant and interestingly, shock resistant. That’s the holy grail for materials engineers.—David Kisailus
The three layers allow small cracks to form, but the differences in hardness and orientation prevent the cracks propagatins. Researcher David Kisailus, “who studies the structures of marine animals for inspiration to develop new materials,” says:
It’s counterintuitive: Mother Nature prevents catastrophic failures by allowing local failures. It’s that architecture that makes them so strong.10
That is, as with so many biological materials, it’s not only the chemistry, but also the fine structure that makes them extremely strong. Kisailus also said:
“This club is stiff, yet it’s light-weight and tough, making it incredibly impact tolerant and interestingly, shock resistant. That’s the holy grail for materials engineers.”
Indeed, a summary article said the shrimp club “has a much higher specific strength and toughness than any synthetic composite material.”11 He sees the immense applications if we can reproduce this design. The reduced weight could cut fuel consumption in electric cars and airplanes, and the increased impact resistance should reduce repair bills. Dr Kisailus also hopes to help soldiers, because at present body armour adds about 10 kg (over 20 lb) to his load. Armour based on this design could be just as strong for a third of the weight.
Dr Kisailus and colleagues received $590,000 in funding from the Air Force Office of Scientific Research to continue their great research. But given the high-class science of making the imitation material, what does it say about the Maker of the original?12
- Sarfati, J., Shrimpy Superboxer, Creation 30(2):12–13, 2008; creation.com/shrimpy-superboxer; based on Patek, S.N. et al.., Deadly strike mechanism of a mantis shrimp, Nature 428(6985):819, 2004. Return to text.
- Details in Sarfati, J., More space travel problems: g-forces, creation.com/g-force, 9 February 2012 Return to text.
- For more explanation, see Catchpoole, D., Beware the bubble’s burst: Increased knowledge about cavitation highlights the destructive power of fast-flowing water, creation.com/bubble, 24 October 2007. Return to text.
- Sarfati, J., Amazing abalone armour, Creation 30(1):44–45, 2007; creation.com/abalone; after Lin, A. and Meyers, M.A., Growth and structure in abalone shell, Materials Science and Engineering A 390:27–41, 15 January 2005. Return to text.
- Marshall, N.J. and Oberwinkler, J., The colourful world of the mantis shrimp, Nature 401(6756):873–874, 1999. Return to text.
- Sarfati, J., DVD makers copy mantis shrimp eye design, Creation 34(2):56, 2012; after ‘Sexy’ shrimp eyes help DVD technology, www.news.com.au, 26 October 2009. Return to text.
- Weaver, J.C. et al., The stomatopod dactyl club: a formidable damage-tolerant biological hammer, Science 336(6086):1275–1280, 8 June 2012: | DOI:10.1126/science.1218764 Return to text.
- Nealon, S., ‘Armored Caterpillar’ Could Inspire New Body Armor: Unique structure of fist-like club of mantis shrimp could transform materials used to create military body armor and vehicle and aircraft frames, ucrtoday.ucr.edu/6737, 7 June 2012. Return to text.
- Sarfati, J., Arthropods inspire strong, biodegradable material, Creation 35(3):56, 2013 (in press), after Inspired by insect cuticle, wyss researchers develop low-cost material with exceptional strength and toughness, wyss.harvard.edu/viewpressrelease/72/, 13 December 2011. Return to text.
- cited in: Telis, G., Mantis Shrimp Smash! Science Now, 7 June 2012. Return to text.
- Tanner, K.E., Small but extremely tough, Science 336(6086):1237–1238, 8 June 2012 | DOI: 10.1126/science.1222642; comment on ref. 7. Return to text.
- As usual, in their main article (ref. 7), there is a fact-free homage to evolution: “Nature has evolved efficient strategies to synthesize complex mineralized structures that exhibit exceptional damage tolerance.” But the objective facts were the amazingly designed arrangements; evolutionary theory provided no practical help. Return to text.
- Mantis shrimp FAQ, blueboard.com/mantis/faq.htm#faq12. Return to text.
The beauty of this site is that sometimes we learn more from the comment section than we do from the actual articles. Bravo!
I’m actually flattered that you responded and published (most of) my comment! For that, thanks. I hope you’ll allow the conversation to continue!
Dr Jonathan Sarfati replies: Of course.
My biggest point, right at the end of the posted comment, was that the appearance of complexity does not necessarily imply a design, and thus doesn’t necessarily imply a designer.
JS: Yet this is a reasonable conclusion from what we do know is the cause of specified complexity, when a cause is known.
Now, I’ll admit, physical chemistry was one of my weaker subjects; I preferred biochemistry and organic chemistry. Having a doctorate yourself, you’d know that complexity in organic chemistry (and biochemistry, which is one of my degrees) can arise on its own, without meddling by the chemist.
JS: Yes I do. And this reinforces that proteins and DNA has a huge information content that is not part of the properties of its monomers. This is very distinct from ice crystals that are caused by the properties of the water molecules, as explained in the above links. E.g. to make proteins by something like Merrifield’s machine, the individual amino acids must be added individually, and each addition has about 90 physico-chemical steps, as chemical evolutionist A.G. Cairns-Smith points out.
I like that you bring up proteins, DNA, and molecular machines, though. We have a rather thorough understanding of just how the complexity in those systems arose, and as far as we can tell they didn’t need a designer.
JS: That is highly debatable. Yes, we have a very good idea of how they operate, purely by physico-chemical laws. We also have good ideas how they are assembled from the plans or instructions in the DNA, again purely by physico-chemical laws. But these don't explain the origin of the plans themselves arose.
As explained before in Responses to our 15 Questions: part 1:
And we would agree that the workings of the code are due to chemical properties—we are not vitalists (see also Naturalism, Origins and Operational Science). But this doesn’t explain the origin of the code. Similarly, we believe that the workings of computer decoders can be explained totally by the laws of semi-conductor electron levels and other electrical properties, but these laws didn’t make the computer.
Now, that doesn’t preclude the existence of a designer, just that this designer didn’t design those systems.
JS: The designer planned these system. I discuss this in The Greatest Hoax on Earth? ch. 5: Embryos and self-assembly. See also The canyon and the panda, about what God actually created in Creation Week vs His current sustaining operations.
Anyway, like I said, my intention was to point this out, not to imply that any commenter (or author) is ignorant or amateurish.
JS: Noted, thanks.
Your argument is meaningless. You have
- Designed things have designers.
- Animals are designed.
- Animals have a designer.
Your first statement is tautological, your second requires substantiation, and your third is a non sequitur.
Complexity doesn’t necessarily indicate design. Indeed, there is not much more complex in nature than ice crystals, and we can show that these crystals occur naturally. …
Your amateurish attempt at a syllogistic summary has already been answered in Who designed the Designer? Note that this is non-tautological:
In contrast, the argument is actually: in objects of known origin, there are certain features—specified complex information—that occur only in those made by an intelligent designer (or an intelligently designed program). So by the normal analogical reasoning we use in science, when we see these features in an object where the origin is unknown, we can likewise conclude that this object had an intelligent designer.
These features are those that an archaeologist would use to determine whether an object was designed by an intelligent designer, or that a SETI devotee would use to argue that a signal from space came from an intelligent alien, or whether a ballot or card game was fixed, or whether a sequence of letters was the result of intelligence or monkeys on a keyboard.
Your claim about ice crystals betrays ignorance of crystallography (which was part of my earned doctorate in physical chemistry). In fact, crystals are low-information repetitive structures, analogous to ABCDABCDABCDABCD which is the low-information ABCD × 4. The proteins, DNA, and molecular machines are complex: they not only have organization but would take many letters to specify it. See more at What about crystals? and a refutation of a critic, and this one more specifically about ice, The treasures of the snow: Do pretty crystals prove that organization can arise spontaneously?
The argument from design has always been very strong when we look at such examples of evidence. It’s quite a simple syllogism, but the reality of it is undeniable, and even Darwin knew it, and seemingly ignored it anyway.
- Clearly elaborately designed things require designers.
- Animals, in an innumerable capacity, are elaborately designed.
- ERGO animals require a designer.
If evolution were true, it is reasonable to suppose that designs would not reach a genius-standard, and we would expect to see examples of tried and tested transitional organisms. Such examples do not exist, evolutionists merely posit that fully designed organisms are transitionals, when it is clear that they are actually complete designs.
The Maker of the original is beyond genius, beyond brilliant. His designs are the envy of engineers and designers everywhere.