Friday, July 26, 2013

Biomemetics This Time: Tunable Photonic Materials

Another Astonishing Design

We have discussed some amazing examples of how species control their color (here and here, for example) and how such technology in nature has inspired engineers creating advanced new technologies such as low-power video displays. Now new research is helping to explain how squids and octopuses change color and it is amazing.

We usually think of color as resulting from chemistry, such as in dyes. But different colors can also result from repeating, detailed submicron geometrical structures at the object’s surface. The new research reveals yet another, even more complex system for manipulating the frequency of light (i.e., the color) coming from squids and octopuses.

It begins with nerve signals which are sent to special cells containing special proteins. The signal causes the proteins to congregate and deep pleats to form in the cell membrane, altering the osmotic pressure and ultimately its refractive index.

Here is how one of the researchers described the process:

Initially, before the proteins are consolidated, the refractive index -- you can think of it as the density -- inside the lamellae and outside, which is really the outside water environment, is the same. There's no optical difference so there's no reflection. But when the proteins consolidate, this increases the refractive index so the contrast between the inside and outside suddenly increases, causing the stack of lamellae to become reflective, while at the same time they dehydrate and shrink, which causes color changes. The animal can control the extent to which this happens -- it can pick the color -- and it's also reversible. The precision of this tuning by regulating the nanoscale dimensions of the lamellae is amazing.

And here is a more technical description, from the journal paper:

Squids have used their tunable iridescence for camouflage and communication for millions of years; materials scientists have more recently looked to them for inspiration to develop new “biologically inspired” adaptive optics. Iridocyte cells produce iridescence through constructive interference of light with intracellular Bragg reflectors. The cell’s dynamic control over the apparent lattice constant and dielectric contrast of these multilayer stacks yields the corresponding optical control of brightness and color across the visible spectrum. Here, we resolve remaining uncertainties in iridocyte cell structure and determine how this unusual morphology enables the cell’s tunable reflectance. We show that the plasma membrane periodically invaginates deep into the iridocyte to form a potential Bragg reflector consisting of an array of narrow, parallel channels that segregate the resulting high refractive index, cytoplasmic protein-containing lamellae from the low-index channels that are continuous with the extracellular space. In response to control by a neurotransmitter, the iridocytes reversibly imbibe or expel water commensurate with changes in reflection intensity and wavelength. These results allow us to propose a comprehensive mechanism of adaptive iridescence in these cells from stimulation to color production. Applications of these findings may contribute to the development of unique classes of tunable photonic materials.

What we see here is a beautiful design consisting of a sequence of highly complex, intricate and finely-tuned mechanisms, molecules and structures allowing these organisms to precisely control their image. There is no scientific evidence that such optical technology arose from random mutations as evolutionists believe. Evolutionists like to call upon natural selection as a sort of natural designer, but that does not help for such intricate designs as these.

24 comments:

  1. Of note: Caribbean Reef Squid: A Conundrum for Neo-Darwinian Evolution? - by Melissa Cain Travis - February 20, 2013
    Excerpt: A spectacular example of a creature that seems to utterly defy naturalistic explanation is the Caribbean reef squid, known by the scientific name, Loliginidae sepioteuthis. These highly intelligent cephalopods (the broader animal category that includes squid, octopuses, and cuttlefish) utilize a stunningly sophisticated mode of communication that is based upon lightening-fast changes in the colors, patterns, and textures they exhibit in their skin. The squid have dynamic structures in their skin called chromatophores that are used to cause these changes. The squid also has special structures that reflect or absorb incoming sunlight to help form all the various skin colors and patterns. The iridescent areas are called iridophores.
    In less than 30 milliseconds (yes, milliseconds!!), and in response to a visual cue, the squid can purposefully change its color and pattern to communicate with another squid, court another squid, stun their prey, or to try and ward off or confuse a potential predator. Many of the color/pattern displays include certain arm postures, as well. The squid can manipulate its color/pattern display in order to make it appear to move across their body.
    http://sciencereasonfaith.com/caribbean-reef-squid-a-conundrum-for-neo-darwinian-evolution/

    Mimic Octopus – video
    http://www.wimp.com/octopusmimic/
    http://www.youtube.com/watch?v=PmDTtkZlMwM

    David Gallo: Underwater astonishments - video
    http://www.ted.com/talks/david_gallo_shows_underwater_astonishments.html
    David Gallo shows jaw-dropping footage of amazing sea creatures, including a color-shifting cuttlefish, a perfectly camouflaged octopus, and a Times Square's worth of neon light displays from fish who live in the blackest depths of the ocean.

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    1. This comment has been removed by the author.

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    2. Famous first lines:

      "I first heard Personville called Poisonville by a red-haired mucker named Hickey Dewey in the Big Ship in Butte. —Dashiell Hammett, Red Harvest"

      The first time I laid eyes on Terry Lennox he was drunk in a Rolls-Royce Silver Wraith outside the terrace of the Dancers. —Raymond Chandler, The Long Goodbye

      Call me Ishmael. —Herman Melville, Moby-Dick


      It was now lunch time and they were all sitting under the double green fly of the dining tent pretending that nothing had happened. Hemingway

      Nobody ever walked across the bridge, not on a night like this. The rain was misty enough to be almost foglike, a cold gray curtain that separated me from the pale ovals of white that were faces locked behind the steamed-up windows of the cars that hissed by. Even the brilliance that was Manhattan by night was reduced to a few sleepy, yellow lights off in the distance. Mickey Spillane


      Someone must have slandered Josef K., because one morning, without his having done anything bad, he was arrested. —Franz Kafka, The Trial (Franzen's translation)

      Up from the skeleton stone walls, up from the rotting floor boards and the solid hand-hewn beams of oak of the pre-war cotton factory, dusk came. —Jean Toomer, "Blood-Burning Moon," from Cane

      I remember the first time I got a letter that said "After Five Days Return To" on the envelope, and I thought that after I had kept the letter for five days I was supposed to return it to the sender.

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  2. podcast - Part 1: Dr. Cornelius Hunter on ENCODE and "Junk" DNA -
    http://intelligentdesign.podomatic.com/entry/2013-07-26T18_13_09-07_00

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  3. Creatures changing their colour is one of the amazing biological actions in nature.
    Its seems impossible for a dumb creature to have any control. they don't think it through indeed.
    its their body reacting to its area.
    I suggest this is the origin for human skin colour and animal coloration details.
    its from innate mechanisms that make the body change as needed.
    These fast changing creatures are just a example in the spectrum of this mechanism.
    They are not really that amazing or different . We people did it too.
    Blacks became blacks within nonths or a few years upon entering Africa and whites became white likewise upon entering europe.
    With people it isn't triggered easily.

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    1. byers, you're a dumb creature who never thinks through anything, indeed.

      So, if a person goes to Africa and stays there for months or a few years they will become a black person, no matter what color/race they were before?

      And if a person enters Europe or stays there for months or a few years they will become a white person, no matter what color/race they were before?

      From where did the people who turned black or white come from and what color/race were they before turning black or white within months or a few years?

      What is it about Africa that makes people turn black within months or a few years, and what is it about Europe that makes people turn white within months or a few years?

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  4. There is no scientific evidence that such optical technology arose from random mutations as evolutionists believe. Evolutionists like to call upon natural selection as a sort of natural designer, but that does not help for such intricate designs as these.

    There is no scientific evidence that it was designed either.

    The difference is that we can observe at least some of the natural processes that contribute to evolution. We cannot say the same for any putative Designer/Creator.

    Yes, the eye, for example, is a wonderful organ. You could argue that it is evidence of a highly-skilled designer. But what of the parasite that can bore its way into that eye and blind it? Is that also evidence of a highly-skilled designer? If so, what kind of designer would do such a thing and why?

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    1. Since when has extraordinary analytical intelligence been indicative of virtue?

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    2. Ian, an inscrutable designer.

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    3. Paul July 27, 2013 at 5:40 AM

      Since when has extraordinary analytical intelligence been indicative of virtue?


      Since Christians conflated the concept of Supreme Being with Supreme Moral Authority.

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    4. velikovskys July 27, 2013 at 9:09 AM

      Ian, an inscrutable designer.


      Perhaps human designers should follow that example:

      "I've designed this thing that looks like it's for opening cans but I'm not telling you what it's really for, so there! Nyah, nyah!"

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    5. And if it cuts someone's finger off,say that was part of the plan from the start.

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    6. Ian,
      Since Christians conflated the concept of Supreme Being with Supreme Moral Authority.



      The moral authority is the hammer without it you might as well worship trees

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  5. Admit it atheists: you see materialism as an indispensable emotional crutch. Luwontin virtually admitted as much, with his now fabled, 'We mustn't allow God a foot in the door' exhortation.

    So, to the question, 'What is it you don't understand about the word, 'No', with regard to materialism? the answer is, 'Everything' - a priori. Fingers in ears: Na! Na! Na! Na! Na!

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    1. Just explain how to do science with supernatural as a variable.

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    3. Aha! A rare sighting of the Lesser Spotted Lewontin outside the Kairosfocus compound at Uncommon Descent.

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    4. paul projected:

      "Admit it atheists: you see materialism as an indispensable emotional crutch."

      You god pushers are the ones with an indispensable emotional crutch. You're the ones with the fairy tale dogma, and churches, and the prayers to an imaginary sky daddy monster, and all the other religious gobbledegook that you believe in and promote.

      You religious nuts are your own worst enemy and you deliberately try to blind yourselves to it. What really scares you is your own thoughts.

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  6. DrHunter,

    There is no scientific evidence that such optical technology arose from random mutations as evolutionists believe. Evolutionists like to call upon natural selection as a sort of natural designer, but that does not help for such intricate designs as these.


    Depends of your concept of design, a screen which filters certain size particle could be said to have designed a pile of certain sized particles and smaller. How do you know that natural selection can't include intricate designs?
    Remember since you do not wish to include teleology in science,these designs cannot be considered a goal

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  7. Cornelius Hunter

    There is no scientific evidence that such optical technology arose from random mutations as evolutionists believe.


    LOL! No scientific evidence at all except for the scientific evidence we do have. Research like

    Evolution of the vertebrate eye: opsins, photoreceptors, retina and eye cup

    and

    Evolution of opsins and phototransduction

    Abstract: Opsins are the universal photoreceptor molecules of all visual systems in the animal kingdom. They can change their conformation from a resting state to a signalling state upon light absorption, which activates the G protein, thereby resulting in a signalling cascade that produces physiological responses. This process of capturing a photon and transforming it into a physiological response is known as phototransduction. Recent cloning techniques have revealed the rich and diverse nature of these molecules, found in organisms ranging from jellyfish to humans, functioning in visual and non-visual phototransduction systems and photoisomerases. Here we describe the diversity of these proteins and their role in phototransduction. Then we explore the molecular properties of opsins, by analysing site-directed mutants, strategically designed by phylogenetic comparison. This site-directed mutant approach led us to identify many key features in the evolution of the photoreceptor molecules. In particular, we will discuss the evolution of the counterion, the reduction of agonist binding to the receptor, and the molecular properties that characterize rod opsins apart from cone opsins. We will show how the advances in molecular biology and biophysics have given us insights into how evolution works at the molecular level.

    But you couldn't find such papers all the places you looked, right CH? Not from Genesis to Revelation.

    Go ahead and use your stock Creationist excuse "But but but THEY ASSUME EVOLUTION!!" That's always good for a chuckle.

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    1. Please go easy on Professor Hunter, or he might stop throwing soft balls in the strike zone.

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    2. Pedant

      Please go easy on Professor Hunter, or he might stop throwing soft balls in the strike zone.


      CH's job is just to throw this inane Creationist crap against the wall. Doesn't matter to him whether it sticks or not, he still gets paid the same.

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    3. Lucky for him, I'm not his boss.

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