The Brachinus crepitans, or bombardier beetle, measures just 2 cm but wields a powerful chemical defense. When threatened, it mixes hydroquinone and hydrogen peroxide inside its abdomen, triggering an exothermic reaction that reaches 100 °C. It ejects bursts of corrosive benzoquinones at 500 pulses per second, burning and repelling predators. This precise, repeatable mechanism has inspired research into reigniting gas turbines in aircraft under extreme conditions as low as –50 °C. Its internal valve and chamber system is now studied in chemical engineering and advanced biomimicry.

  • MeatPilot@lemmy.worldEnglish
    2·
    8 hours ago

    For a good read, look for “For the Love of Insects” by Thomas Eisner who studied the bombardier beetle. The book doesn’t focus on bombardier beetles. But he does go over how he made some discovers on the bombardier beetle.

    Eisner was a wonderful scientist with a fascinating perspective.

  • Aceticon@lemmy.dbzer0.comEnglish
    14·
    20 hours ago

    Only a couple more million years of natural evolution before we beetles capable of jet-powered flight…

    • GiveOver@feddit.ukEnglish
      61·
      12 hours ago

      Here’s an attempted explanation

      Quinones are produced by epidermal cells for tanning the cuticle. This exists commonly in arthropods. [Dettner, 1987]

Some of the quinones don't get used up, but sit on the epidermis, making the arthropod distasteful. (Quinones are used as defensive secretions in a variety of modern arthropods, from beetles to millipedes. [Eisner, 1970])

Small invaginations develop in the epidermis between sclerites (plates of cuticle). By wiggling, the insect can squeeze more quinones onto its surface when they're needed.

The invaginations deepen. Muscles are moved around slightly, allowing them to help expel the quinones from some of them. (Many ants have glands similar to this near the end of their abdomen. [Holldobler & Wilson, 1990, pp. 233-237])

A couple invaginations (now reservoirs) become so deep that the others are inconsequential by comparison. Those gradually revert to the original epidermis.

In various insects, different defensive chemicals besides quinones appear. (See Eisner, 1970, for a review.) This helps those insects defend against predators which have evolved resistance to quinones. One of the new defensive chemicals is hydroquinone.

Cells that secrete the hydroquinones develop in multiple layers over part of the reservoir, allowing more hydroquinones to be produced. Channels between cells allow hydroquinones from all layers to reach the reservior.

The channels become a duct, specialized for transporting the chemicals. The secretory cells withdraw from the reservoir surface, ultimately becoming a separate organ.

This stage -- secretory glands connected by ducts to reservoirs -- exists in many beetles. The particular configuration of glands and reservoirs that bombardier beetles have is common to the other beetles in their suborder. [Forsyth, 1970]

Muscles adapt which close off the reservior, thus preventing the chemicals from leaking out when they're not needed.

Hydrogen peroxide, which is a common by-product of cellular metabolism, becomes mixed with the hydroquinones. The two react slowly, so a mixture of quinones and hydroquinones get used for defense.

Cells secreting a small amount of catalases and peroxidases appear along the output passage of the reservoir, outside the valve which closes it off from the outside. These ensure that more quinones appear in the defensive secretions. Catalases exist in almost all cells, and peroxidases are also common in plants, animals, and bacteria, so those chemicals needn't be developed from scratch but merely concentrated in one location.

More catalases and peroxidases are produced, so the discharge is warmer and is expelled faster by the oxygen generated by the reaction. The beetle Metrius contractus provides an example of a bombardier beetle which produces a foamy discharge, not jets, from its reaction chambers. The bubbling of the foam produces a fine mist. [Eisner et al., 2000]

The walls of that part of the output passage become firmer, allowing them to better withstand the heat and pressure generated by the reaction.

Still more catalases and peroxidases are produced, and the walls toughen and shape into a reaction chamber. Gradually they become the mechanism of today's bombardier beetles.

The tip of the beetle's abdomen becomes somewhat elongated and more flexible, allowing the beetle to aim its discharge in various directions.
        • trevdog@lemmy.worldEnglish
          2·
          9 hours ago

          idk why but I kind of like to read it with random keywords highlighted and every apostrophe toggling the effect

        • bitwolf@sh.itjust.worksEnglish
          1·
          9 hours ago

          I tend to use them because they’re easier than quotes.

          Newlines won’t terminate the block but with quotes you have to manually insert a > at each linebreak.

    • Hirom@beehaw.orgEnglish
      7·
      19 hours ago

      The same way every living thing evolve. Through millon or billion of years of mutations and natural selection.

    • Mothra@mander.xyzEnglish
      23·
      1 day ago

      I’m from Buenos Aires and didn’t know about the existence of this meme

      TIL

      • teft@piefed.worldEnglish
        1·
        2 hours ago

        You have to watch Starship Troopers. One of the best satirical military action films of all time.

        • Mothra@mander.xyzEnglish
          7·
          1 day ago

          After knowing about the meme I looked up the movie and I’m sure I watched at least part of it when I was a kid, on air tv. I remembered the bug designs, which were the reason it caught my interest, I remember the action scenes with the bugs were fun, but I also remembered the plot and acting was a bit lacking.

          I didn’t remember the “I’m from Bs. As.” line, I’m sure I would have found that absolutely hilarious even back then. Maybe I forgot or maybe I got too distracted during the several commercial breaks and missed some bits, can’t say

          • Cethin@lemmy.zipEnglish
            4·
            15 hours ago

            It’s a purposefully campy movie. It’s inspired by an actual fascist novel, but they’re making fun of it in the movie. It’s a really good watch, but you have to be fine with the camp.

            Alternatively to the movie, or better in addition to, you should watch this.

    • brem@sh.itjust.worksEnglish
      6·
      1 day ago

      According to this theory, every action that I take in this body is a direct result of evolution; which: according to my research on humans . Is entirely correct.

  • Coolbeanschilly@lemmy.caEnglish
    16·
    2 days ago

    This beetle is the natural equivalent of passing Taco Bell while listening to Johnny Cash’s “Ring of Fire”.