SEM arthropods

March 17, 2011 • 9:20 am

Here, from a Daily Telegraph posting, are some lovely pictures of arthopods taken with a scanning electron microscope.  All photographs are by Steve Gschmeissner, courtesy of Science Photo Library and Barcroft Media.  (For more of Gschmeissner’s amazing SEM photos, see here and here.)

First, the common dog flea, Ctenocephalides canis:

A honey bee (Apis sp.):

A jumping spider in the Salticidae:

A soldier turtle ant (Cephalotes sp.)

The head of a tropical caterpillar, species not named:

A wasp, species not named:

The human flea, Pulex irritans:

38 thoughts on “SEM arthropods

    1. I was going to ask the same thing, whether they are false color images. I’m pretty sure they are. Which, I must say, I appreciate because it makes it easier to pick out individual parts. Very cool!

    2. All the colors are false. SEM is grayscale only.
      I loathe the practice but nobody ever agrees with me when I complain.

      1. IMO it can really help one envision distinct features. I’d like to see both grayscale and colorized versions presented together…though I agree with The Big Blue Frog that that needn’t be necessary for these popular sorts of uses…A little note pointing out the artificiality would be nice, though.

        1. Color is often used to enhance the perception of detail. It just gives us more information in a way we’re more accustomed to seeing things. “Art” aside, it’s useful.
          When looking at neurons, dyes are often used to enhance feature detection

    3. Late to the party but same initial reaction, too. Who knew Ted Turner was an electron microscopist?

    4. SEM, or scanning electron microscope, is not using photons, so no color.

      The link Rocket provided shows how it is done: a collimated electron beam interacts with a sample, and non-intuitively a detection of back-scattered electrons (or the current used) is used to assemble an image out of the sweep. The best way to look at it [sic!] may be to envision an inverted eye building up image information, the way that children naively sees vision (“eye beams”).

      This “exciting in a point” image assembly technique as opposed to the eye “detecting in a point” focal plane image assembly is also a general method (from ultrasounds over x-rays to atomic force microscopes).

      1. I think that if they use several wavelengths of electrons you can give it false-color information which isn’t meaningless coloring. It’s like IR pictures have color, but just different from what we’re used to.

    1. Yes, and as a severe waspophobic (I fell into a nest of them when I was six years old), it’s gonna give me nightmares…

  1. Obviously, the “Face of God” is the ant. The ant population on the Earth is equal, by weight, to the human population. So, simply by pure “head count”, the directive to “go forth and multiply” has been carried out far more successfully by ants.
    Indeed, those antennae are far more useful for sending information across the vacuum of space (so much a feature of the known universe).

    So the question not be “Is There a God?” but rather “For What Reason Would God Not Be An Ant??”

    1. no, the eyes are the slightly rounded structures below.
      Those things are the ‘antennal fossae’ into which the antennae can be tucked.

  2. I’m sorry, one of the captions under the pictures said “human flea”. This must be an error. If not, I must lie down.

  3. Absolutely beautiful pictures.

    That said, I still don’t think I’d ever want to cuddle one. Evolution has gifted me with a built in yeuch reaction to these critters.

    I wonder why. They are furry, have two eyes… but somehow they are not the same as puppies. The only “cute” insect out there (that I know of) is the tardigrade.

  4. On the jumping spider, are the pink-colored scales(?) parasites? Particularly around the forward facing eyes …

    1. Interesting. One does want detailed descriptions upon viewing these images!

      I’ve seen several images of phoretic or parasitic mites on arachnids. Zooming in on these pink objects doesn’t cause anything that resembles those critters to appear…These objects also look very similar to the same colored objects on what looks like the pedipalps, where they seem to be lined up rather evenly. My money would be on the hypothesis that they’re a type of special sensory hair. Arachnids have been shown to have quite a few specialized setae like that…

  5. This site is the top three results in Google when you search for Putrex irritans.

    That would appear to be because there is no such thing.

    Pulex irritans is the name of the human flea. Better go lie down now, Helen.

  6. Bilateral symmetry. What drives it? Striking from these photos.

    I’m sure Mr. Google will help me out but perhaps if Jerry could put down his fork for a minute or two it would be an interesting topic for a post!

    p.s. Kink says “hai”

  7. Striking (really!) images, but I would dearly want to know how much asymmetry comes from the specimen preparation vs individual development. How does symmetry scale between larger and smaller mesoscale multicellular individuals?

    Or in other words, is symmetry for us a result of sexual selection specifically, or is it “symmetry all the way down” for reasons of fitness?

    I’m guessing the requirements is relaxed for smaller scales (because surely allowed asymmetry of individual cells is the end of the scale). But can it be quantified, and is the nice symmetry we can see in the images above merely a result of our pattern search for such?

  8. I can’t get over these images.

    There’s this microscopic machine world competing in an economy operating on a much smaller scale than us humans. Just look at them! They have an alien quality which is fascinating. Evolution literally blows my mind.

    Numbingly good.

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