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Issue Date: June 11, 2012 Web Date: June 7, 2012
How A Peacock Shrimp Packs A Punch
News Channels: Biological SCENE, Materials SCENE, Analytical SCENE
Keywords: shrimp, body armor, biomaterials
Anybody who has repeatedly punched a wall knows that one’s fist typically suffers as much damage as it inflicts. In contrast, four-inch-long peacock shrimp living in the Pacific and Indian Oceans repeatedly smash through the shells of unsuspecting prey without damaging their own pretty red clubs. That capacity is due to unique layering of stiff and compliant materials in the animal’s club, researchers report in Science (DOI: 10.1126/science.1218764). The club’s chemical makeup could provide a blueprint from which to design resilient materials for body armor and shields.
Less than a quarter-inch long, the shrimp’s club strikes with 200 lb of force, enough to break a glass aquarium, says David Kisailus, a chemical engineer at the University of California, Riverside. “Its club accelerates faster than a .22-caliber bullet, and all this happens underwater,” he adds. “It can also strike thousands of times without breaking.”
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Kisailus and his colleagues used scanning electron microscopy, X-ray diffraction, micromechanical testing, and computer micromechanical modeling to establish that the club’s strength is a result of the cooperation of three layers of materials.
The impact surface of the club is made up of extremely dense hydroxyapatite. The compressive strength of this region is greater than that of high-temperature engineering ceramics such as zirconium oxide and silicon carbide, Kisailus says. Below the hydroxyapatite is a more compliant layer composed of chitin fibers arranged in helical spirals and surrounded by amorphous mineral. Finally, more chitin wraps around the edges of the club. Unlike the helical chitin fibers in the second layer, these chitin fibers are parallel to each other. The arrangements of both chitin fiber layers, as well as the interface between the hydroxyapatite and chitin regions, prevent major cracks.
“Modern body armor also makes use of a layered structure . . . . However, the ceramic plates [used] fracture on impact and have to be replaced,” says K. Elizabeth Tanner, an engineer at the University of Glasgow, in Scotland, in an associated commentary in Science. Engineers may wish to look to the shrimp’s club to improve the impact resistance of shields over multiple blows, she adds.
- Chemical & Engineering News
- ISSN 0009-2347
- Copyright © American Chemical Society
I find it rather amusing to see anyone who thinks such fantastically complicated things such as human brains, peacock mantis shrimp clubs, or even the wing structures of flies, could be "designed" by some being. Perhaps this "being" is really just a representation of the natural flow of things, or the idea of the persistence of life in our universe. After all, our strongest supercomputers only rival the brains of small rodents. Our strongest engineering materials are orders of magnitude weaker than the naturally evolved "clubs" of peacock mantis shrimp. To think that any physical or metaphysical being could even begin design or understand something as complex as the human brain, let alone the entire human body, is somewhat naive. A more realistic and holistic idea is that these things arose out of necessity. After all, why would a peacock "shrimp" need super-strong clubs? If not for the incredible strength of its prey's shells, these clubs never would have evolved. If some supreme being "designed" the peacock shrimp, why not also design its prey to have weaker, more easily cracked shells? Did this supreme being think the shrimp should "work harder" to get dinner? I wouldn't bother making something incomprehensibly strong if I could make it not necessary.
This is a very complicate debate, and I hope it brings forth a fruitful discussion.
-Z
Simply put, there is no test that you can use to directly determine if a material was designed or evolved. Why is that? Because the structure and ordering of a material gives no indication how it was originated. (unless you already know how that material originated, then you're just matching material)
In past experiments, scientists have created evolutionary systems, where a structure or device goes through huge numbers of evolutionary generations. These experiments were done to see how an evolutionary process would work in a different environment.
In one such experiment, a silicon circuit evolved to the point where it performed it function correctly, but no one, not even the high level scientists who were experts in silicon circuit design, could understand how it worked. The circuit appeared to be totally disconnected from it inputs, and yet performed the work perfectly.
The evolutionary process had discovered and used a property of silicon materials that scientists had never seen before.
btw- the peacock shrimp is the result of evolution, and guess what? Its still evolving, just like we are.
Next question?
The theory of evolution is not like your theory that you could skate on thin ice, like just some hunch you had one day. Evolution is based on actual real evidence that's been building up, and that we can see all around us.
That doesn't eliminate God or deny his existence, it just doesn't mean that god made this creature like this at the beginning of time. Is there some hand guiding the evolution? maybe, but we have a scientific theory that explains it just fine, and you'll have to look elsewhere for your evidence.
You can bet that if it was created according to design, you would not be able to pinpoint the difference to evolution. God does not do things half-baked, so don't use cheap excuses for not studying his greatness in creating a world consistent with having existed billions of years. If it pleased the Lord to create such a world, it would be heresy to refuse marveling at how all its details make sense.
He worked for years and years. He knew his task. The tiny critters he so loved needed a way to capture and eat the armored animals created by the designer's bitter rival. The years passed as he worked. He tried over and over and over again. His first designs were feeble and didn't really work. Most of his creations died off, but some got lucky by striking at young and weak prey. He was persistent. He started to learn the tricks of the materials he had to work with. He kept trying. As new arrangements saw faint promise, he concentrated on improving those designs. After many years he had made some progress but started to despair that he would never complete his task. He began to try wild solutions, just for fun. One day, by dumb luck, he made a multi-layered design just for the artistic beauty. He had used some of his (by now) well known solutions. He found that the little weapons on his beloved creature were the perfect weapon for hunting the prey it needed to live, thrive, and survive. It was finally able to rest, after all those aeons. He decided it was time to get married, so he called up his lawyer to draft a prenuptial agreement...
The end.
Oh wait...
The Design is to Evolve, period.
1. You clearly misunderstand the process of natural selection. Mantises probably don't choose their mates (some animals do, however I suspect these do not). What happened was that they were more or less forced to mate with shrimps possessing smasher-based raptorial appendages or spearing, depending on the habitat and available resources, because the ones that weren't as well fitted tended to die off more quickly.
2. Mantis shrimps are not true shrimps. Go figure. There are no known species of mantis shrimp without raptorial appendages. They may fall off but they grow back eventually.
3. Mutation? You know that those can be observed and a deity can't right?
4. "Prove to me that there is no God."
Prove to me there wasn't an invisible pink unicorn drinking invisible pineapple juice watching you while you were typing this comment. You can't disprove a flying spaghetti monster either...or a plasmatic bird rib located in the core of a planet 569847895297685976897956576123111045 light years away that cannot be detected by any technology past, present, or future.
You are making the positive claim that a god exists (and a supernatural omnipotent completely beveolent perfect one that sends people to hell and designed imperfect creations at that), thus the burden of proof rests upon you. You must prove it, you can't say "well you can't disprove it" or look at all the crazy crap we'd be believing.
Kindly record atomic absorption spectrum (AAS) to find out % of any metals or its oxides along with chitin moiety. I think it may be due to some metal organic frameworks observed between chitin and metals which makes the shrimp to give more powerful punches without any damage.
Please record HR-TEM equipped with EDAX to find surface morphology information and record X-ray photo electron spectrum to find various metals electronic configuration present in shrimp.
Also record FT-IR, FT-Raman, powder XRD, FE-SEM for further informations.
From the above methodologies one can find out the tough nature of shrimp.
Moreover, exploting this research would make armamaent chemist to build a safe and effective body armour and other biomaterials for furistic application.
These are all my OWN suggestion which I would like to express to top scientists, since giving a spark is more important.