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Tuesday, May 27, 2014

Trilobite Eyes, Pixels, Surgery, and your Smart Phone

      Trilobite compound eyes have always intrigued me. The calcium carbonate of the eyes of these Paleozoic-aged marine arthropods (similar to those of horseshoe crabs and insects) are often well-preserved:



     These extinct creatures have a three-lobed body:






     Their eyes contain many individual lenses (akin to each one creating a pixel) 







unlike those of humans, which is a useful adaptation used in laparoscopy and which may be used in Smart Phones, if/when the technology gets small enough:


Surgery, Smart Phones, and Compound Eyes


     Compound eyes are especially useful in low light situations and in order to be able to see 360 ° to be aware of predators:


     Experience seeing like an insect (it's NOT what you think)


      A recent paper describes discovery of the not-usually-fossilized soft parts of the trilobite eyes as flower like:


          Discovery of trilobite eye soft parts





     I think it might make me see a little buggy though.


     To end today: Tri a lo' bite of this quote: 


     "I cannot stress often enough that what science is all about is not proving things to be true but proving them to be false." -Lawrence M. Krauss, theoretical physicist (b. 1954) 


What do you think?


Steph

(aka Word Woman)









35 comments:

  1. It's important to remember that the pattern of light picked up by the photoreceptor cells is only the start of the story. A lot of visual processing takes place in the periphery: edge detection, contrast enhancement, movement perception, etc. A good place to start reading about this sort of thing is Jerome Lettvin's 1959 paper, What the Frog's Eye Tells the Frog's Brain.

    Also, remember that honeybees can see well into the ultraviolet range, and can perceive polarization of light as well, making their view of the world a lot more remarkable than the second site above suggests.

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  2. Looking forward to jumping into the frog's brain paper. Edge detection and contrast enhancement are a pretty big part of image enhancement techniques in our pixelated world...

    The second site above would not play on my device, so I did not test it. It was sent on to me by a friend. I will see if I can find a more remarkable example. Plug-ins are not playing. . .

    I was hoping to show that the insects don't see a scramble of images as I learned somewhere along the way.

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  3. Ah, It is all coming into focus now…
    The 1970s. Disco. Giant mirror balls rotating above like heavenly orbs. The BEE Gees! Ro(BEE)in, (BEE)arry and (BEE)oris Gi(BEE)(BEE)!

    LegoLovaDaDonnaSummerTrill-o-bite

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    Replies
    1. Don't worry, BEE happy! And here's hoping the world bee population is happier soon. . .

      Trill-o-bite--trilling, Lego!

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  4. The Frog's Eye paper was fascinating (including the statement on p 11 about proving something false, tieing into L. Krausse's statement at the end of my post). That frogs would starve if their food did not move was a revelation.

    How we can actually know what the frog eye sees is still a bit of a mystery, though? How can we really know what they see--completely? How do we know, for that matter, what another human actually sees?

    Thanks for the link to the frog paper from the 1950's--still relevant info. And, thankfully, new frogs didn't have to undergo those experiments. There's those Mark Twain frogs again!

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  5. It's not a solstice. It's not an equinox. Not a perihelion or apehelion. It's Manhattanhenge. Celebrate with a Manhattan, or a Salisbury Steak, I guess.

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    1. Manhattanhenge is inspired, jan. I will let friends in NYC know today is the day for a building-framed sunset. NdGT's comment about the 5/29 and 7/12 dates marking War and Baseball was right on (even if the date wasn't).

      My favorite part of the article: "While we are on the subject, when viewed from all latitudes north of the Tropic of Cancer (23.5 degrees north latitude), the Sun always rises at an angle up and to the right, and sets and an angle down and to the right. That's how you can spot a faked sunrise in a movie: it moves up and to the left. Filmmakers are not typically awake in the morning hours to film an actual sunrise, so they film a sunset instead, and then time-reverse it, thinking nobody will notice."

      Have a great Manhattanhenge, New Yorkers!

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  6. I was not familiar with the work of Dr. Krauss. Investigating, I happened onto this:
    http://www.nytimes.com/2012/03/25/books/review/a-universe-from-nothing-by-lawrence-m-krauss.html?_r=0
    I have nothing original to add at this point; still trying to think it through.

    What on Earth is that structure behind he kindergartners? It is on Earth, isn't it?

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  7. Hi Paul,
    Thanks for the article on Krauss. I will read it tomorrow after aching hiking muscles have been assuaged. Staunton Ranch was a great place to celebrate with a hike with friends and Maizie.

    As to the structure: it's an airplane that I teach in on Fridays. It was dragged down a major Denver street in the 70's to make the current kindergarten classroom. Yes, it is here on Earth. Pretty cool place to start your elementary years ;-)

    Let me know when you think it through more. I'd be interested in where your brain goes with the Krauss stuff.

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    1. Opening windows on unpressurized planes are pretty common. Commercial airliners were unpressurized until the Lockheed Constellation was introduced. The plane I used to own had a canopy that slid back, and could be opened in flight. Good ventilation, but noisy!

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    2. I guess all those older planes did have open cockpits, come to think of it. I would have thought a DC-7 young enough not to have windows that open (except the emergency windows). The kids are always surprised when windows on the planes they ride in don't open.

      I bet it's really fun to fly with the top down.

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    3. I suppose some remodeling was done to the DC-7 to make it suitable for a classroom, but how many of the original features were retained -- the instrument panels in the cockpit, for example?

      Here's another take on A Universe from Nothing(which I realize may not be the source of the quote you originally presented). More to think through ... and then there's the comments ... it just might take me forever. Anyway, I don't think it's elephants all the way down; and I don't think it's nothing all the way down; but maybe the something keeps changing (preferably continuously and differentiably). And, for that matter, why not all the way up?

      Did you have a Happy Birthday?

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    4. Paul, all the instrument panels in the cockpit are still there, as well as the original tiny bathroom with sliding lock, towel dispenser, and doorway. They have added a sink, air conditioning, and two exterior ramps. As a space to teach in it is a bit problematic but we have learned to do things lengthwise.

      Graduation was a blast. Marco's' Greek family at the ceremony included 30 people! Very fun and completely "My big, fat Greek Graduation."

      I read this new article one time through and found it more readable but still much to think over. All the way up, indeed.

      It was a wonderful birthday. Thank you for asking. A brunch with Smith friends, hike with Maizie and a neighbor, and dinner at a lovely Mexican restaurant were part of a gorgeous Saturday here in Colorado.



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  8. Given our recent teeth discussions, I thought this was especially timely (from 5/30/14):

    http://sciencefriday.com/segment/05/30/2014/laser-blast-can-regrow-teeth-in-rats.html#path/segment/05/30/2014/laser-blast-can-regrow-teeth-in-rats.html

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    1. I've had dentists use lasers to photopolymerize composites in my mouth for years, and have never noticed any new teeth popping up. Probably just as well; I'm cranky enough already, without teething again. Maybe stimulating stem cells is how this baldness treatment that I've made fun of when I see it advertised in the Sunday NY Times Magazine is supposed to work. It's probably snake oil, anyway. This one looks even snake-oilier, but the dorky helmet probably keeps the NSA from reading your thoughts.

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  9. Ha, jan! I would welcome shark teeth though. Dentists would be out of business.

    Those close-ups of hair follicles are pretty creepy. Never thought about the helmet having that effect but I bet you're right!

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  10. Paul, I read the article you cited about Krauss 4 times and I still can't completely make sense of it:

    http://www.nytimes.com/2012/03/25/books/review/a-universe-from-nothing-by-lawrence-m-krauss.html?_r=0

    The quote came from A Word A Day and I thought it would promote discussion.

    The referral to "nothing" as being a quantum vacuum. Something vs. nothing. Does Krauss actually call religion dumb? I think I'd have to read his book to understand more...or understand less.

    And how does it fit into his statement about proving things false vs. true?

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    1. Back in my 'proving things' days, I was enamored of reductio ad absurdum.
      Does that help?

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    2. That does help, Paul.

      Have to agree about proving days, though. They are way back there. . .

      Delete
  11. Monday diversion into words, grammar, and punctuation:

    http://m.tickld.com/x/15-grammatically-correct-sentences-that-most-people-find-impossible

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    1. What, no mention of how the panda eats, shoots and leaves?

      Thyme fur uh ferry tail.

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    2. Little Read Riding Hood ;-). Thanks for the link, jan.

      Yeah, eats, shoots and leaves is a classic. So much meaning in an Oxford comma, or lack thereof. Thereof: now there's a fun word!

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    3. chris where pat had had had had had had had had had had had a better effect on the teacher

      that that is is that that is not is not is that it it is

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    4. Thereof, I know whereof I speak. I think.

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  12. Sometimes, the intersection of science and art is just really weird. Lend me your ear.

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    1. Additional info on this:

      The Center for Art and Media in Karlsruhe says the replica ear
      consists of living cells grown from samples provided by Lieuwe van Gogh,
      the great-great-grandson of Vincent's brother Theo.

      The museum says Lieuwe and Vincent van Gogh share about 1/16th of
      the same genes, including the Y-chromosome that is passed down the male
      lineage.

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    2. Ha! That was my exact question: how did they get VVG's DNA? Thanks for the answer, jan, before I posed the question.

      So weird. And interesting...

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    3. I knew that name was familiar: Lieuwe van Gogh is the son of another Theo van Gogh, a film director (great-grandson of the painter's brother), who was assassinated on 11/2/2004. He worked with the Somali-born writer Ayaan Hirsi Ali to produce the film Submission, which criticized the treatment of women in Islam and aroused controversy among Muslims.

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    4. Any idea how to pronounce Lieuwe?

      I had remembered that name in that context...

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    5. I would guess something like "lyoovuh". My wife says Dutch sounds like a throat disease.

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    6. I'm sure it's cognate with "lion". Also, van Gogh isn't pronounced the way most Americans think; that last bit is the guttural that doesn't exist in English. L'Chaim!

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    7. Compare that stat about 6 comments ago, "Lieuwe and Vincent van Gogh share about 1/16th of the same genes", with the popular notion that humans share 50% of our DNA with a banana. Makes the 19th Century sound really long ago!

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  13. Good thing they have tulips. ;-)

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    Replies
    1. Though they may not need them. ;-)

      L'Chaim, indeed!

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