Swell insects from Mozambique

September 2, 2012 • 10:46 am

Today’s New York Times Magazine has a nice slideshow showing insects captured as part of a project to survey the group in Mozambique. As the paper explains:

Earlier this year, scientists from Harvard spent two months documenting insects in Mozambique. This was the first step in a long-term project, led by the biologist E. O. Wilson, to survey all life — and then help restore it — in the Gorongosa National Park, which was nearly destroyed by the country’s civil war. To avoid killing his portrait subjects, one of the entomologists, Piotr Naskrecki, built an open-air studio of white fabric that the bugs were free to flee if they wanted. Some did, forcing Naskrecki to chase them down. Others stayed — perhaps out of curiosity. ‘‘They will look at you, they will judge you,’’ he says. ‘‘They were very suspicious of the camera, and they were very wary of me. I’m sure that none of these animals had ever seen a human. They did not know what to make of us.’’

These wonderful photos are all from Piotr Naskrecki; he’s added a comment—#11 below—and do have a look at his website, which is filled with gorgeous photos of insects and other animals. This is definitely a site worth following if you love animals, photography, or just the wonders of evolution.

I’m mostly showing insects that are either cryptic (camouflaged) or aposematic (brightly colored so as to advertise their noxiousness or toxicity):

A zebra katydid, said to mimic an acacia leaf:

Here are some acacia leaves:

A praying mantis said to resemble a curled leaf. Regardless, it’s certainly cryptic, and the eyes are freaky:

Two aposematic grasshoppers explicitly identified as eating toxic plants. Predators learn to avoid the bright colors after sampling one. (In some cases—though probably not these—predators might have evolved an innate avoidance of the patterns since those who ate the toxic animals might leave fewer offspring. In such cases natural selection could favor an inborn repugnance toward certain colors or patterns. This has happened with some American birds who avoid the black/red/yellow patterns of coral snakes even though they’ve never seen one. But coral snakes are deadly, and selection favoring avoiding the pattern would be much stronger than selection operating when you get a bellyache after eating a toxic grasshopper.)

Finally, the creationists’ favorite insect: the bombardier beetle, which, when disturbed, mixes two chemicals from glands in its abdomens, creating a toxic, boiling-hot mixture that it sprays on enemies and predators.

Creationists used to say that this insect could not have evolved (ergo Jesus), since there was no conceivable intermediate evolutionary step in which the beetle wouldn’t explode from its own chemicals. But that’s long since been refuted since we have a plausible series of intermediate steps that could lead to this condition.  See the bombardier-beetle page at TalkOrigins for an explanation.  In the meantime, the mechanism whereby this beetle defends itself is pretty amazing. From TalkOrigins:

The mechanism of their spray works thus: Secretory cells produce hydroquinones and hydrogen peroxide (and perhaps other chemicals, depending on the species), which collect in a reservoir. The reservoir opens through a muscle-controlled valve onto a thick-walled reaction chamber. This chamber is lined with cells that secrete catalases and peroxidases. When the contents of the reservior are forced into the reaction chamber, the catalases and peroxidases rapidly break down the hydrogen peroxide and catalyze the oxidation of the hydroquinones into p-quinones. These reactions release free oxygen and generate enough heat to bring the mixture to the boiling point and vaporize about a fifth of it. Under pressure of the released gasses, the valve is forced closed, and the chemicals are expelled explosively through openings at the tip of the abdomen. [Aneshansley & Eisner, 1969; Aneshansley et al, 1983; Eisner et al, 1989].

Evolution is cleverer than you are.

29 thoughts on “Swell insects from Mozambique

  1. Gorongoza is a bloody wonderful place. By the way, eating one of those pyrgomorphid grasshoppers (the second one) might give you more than ‘a belly ache’ – they might actually put you in a grave. The ‘rooibaadjie’ (redjacket) grasshopper is, I believe, particularly nasty.

    1. That’s interesting. I had no idea there were toxic grasshoppers, or that the brightly colored ones might be aposematic. I’d assumed it was for species recognition, or something. The second one is reminiscent of some I’ve seen in dry forest in western Mexico. Now I’m wondering about those. Glad I didn’t try eating one.

  2. …aaaand, meant to add – that beautiful katydid at the top is called Terpnistria zebrata and you wouldn’t have to go all the way to Gorongoza to see it: it is common across southern Africa. But don’t let that put you off going to Gorongoza if you have the chance 🙂

  3. “Creationists used to say that this insect could not have evolved (ergo Jesus), since there was no conceivable intermediate evolutionary step in which the beetle wouldn’t explode from its own chemicals.”

    You know, I wish these folks would at least take their own game seriously. If they’re going to say that God did it, give us some kind of religious explanation of what’s going on – why would God have possibly bothered to create a “beetle, which, when disturbed, mixes two chemicals from glands in its abdomens, creating a toxic, boiling-hot mixture that it sprays on enemies and predators”?!

    Instead we already know the answer they’d give – “God works in mysterious ways”. That’s the problem with creationists, they’re not even good at the religion part.

    1. I mean, think about it. If you’re providing a religious explanation, you’re not constrained to the observable facts or the laws of physics or any of that crap. The field is wide open; you can make up whatever entertaining fiction you want. And instead the best they come up with is “I dunno”. No imagination, these people.

  4. Some creationists still do say that the Bombardier Beetle couldn’t have evolved (e.g. AIG still has a page up which says that) and a quick search produced several pages on other creationist sites which imply that without quite saying it explicitly.

    1. And you expected a Creationist to have anything which vaguely resembles intellectual honesty?
      Why did you have that expectation?

  5. For what it’s worth, Eisner and others have worked out the explosive mechanism for species of the genus Brachinus — a widespread, common group of ground beetles. Properly the common name “bombardier” should refer only to Brachinus… although “farting beetle” is the natural, spontaneous tag just about every kid comes up with when they hear them in action.

    The NYT insect is a paussine ground beetle — a rather large, mostly tropical group of specialized ant-nest “social parasites” that are not at all closely related to the true bombardiers..

    I’m not familiar with the mode of “explosive” discharge of defensive fluids in this group, but it’s clear that it’s separately evolved from the Brachinus group.

    But… both are simply improving on delivery mechanisms for secretions of the pygidial glands. This is a basic defensive strategy [and corresponding structures and physiology] found throughout the carabid ground beetles.

  6. I’m mostly showing ones that are both cryptic…and aposematic

    I think you mean either cryptic or aposematic. I’m guessing there are vanishingly few insects that are both cryptic and aposematic.

    1. Maybe not insects, but I once saw a fish tank in a shop window that had a sign saying:

      ‘Caution. Invisible venomous fish.’

      That’s close, isn’t it? I mean, you’d know to leave it alone as soon as you realised it was invisible.

      1. There are lots of insects that practice both crypsis & what’s usually called “startle” coloration (which may or may not be aposematic, and may or may not be mimicry of aposematic critters)… underwing moths, loads of grasshoppers, etc. It generally works by having brightly colored wings that are hidden most of the time.

        1. Now you mention it, the Squacco Heron, Ardeola ralloides has the same feature: dull brown when standing, but flashing brilliant white wings when it takes off. I don’t know whether the colour performs the same function, and a quick search didn’t shed any light, but a couple of them have certainly startled me when they took off nearby.

  7. Wow! Those are some ugly bugbees. I thought we had some funky looking insects in Tucson, but these Mozambique bugs take the cake.

    1. Where wouldI get some. Or a recipe?
      No, seriously. I have a friend who combines a Ph.D in chemistry with a zymurgical hobby (beer making). This might tickle his fancy.

  8. Thanks for this post, anything that will help attract attention to Gorongosa is deeply appreciated. (Could I only ask that the spelling of my name is corrected? It is a tough one, even by Polish standards:-)

    1. Indeed, and I apologize for the misspelling. It’s now been corrected, and I’ve added a link to your website.

      Your photographs are wonderful, and we all appreciate them. Some of our readers are photography buffs, and if you don’t mind, perhaps you could comment here on the equipment and conditions under which you took the photos?

      Thanks again,

      1. Thanks for the correction, much appreciated.

        All these photos were taken in the Gorongosa National Park in Mozambique, and show live insects that I photographed in a small outdoor studio. The background is a piece of white plastic, which was placed in a small, white shooting tent, the kind that is often used for photographing jewelry and other small objects. The lighting was provided by three external flashes (Canon 580EXII) mounted on tripods; the lights were triggered remotely by the camera. All these photos were taken with a Canon 7D SLR camera, and either Canon 100mm or Canon MP-E 65mm macro lenses.

        This type of nature photography that isolates the subject from its background has been recently popularized by the project Meet Your Neighbours (meetyourneighbours.net), which aims to highlight the beauty and diversity of small organisms that live all around us. Definitely worth to have a look, you will be surprised at the range of organisms that people find in their backyards.

  9. The photos are lovely. I especially like the mantis and the amazing antennae on the bombardier beetle. It is nice to see “collecting” done with a camera rather than a killing jar. This project is inspiring and sets a wonderful example.

  10. Can insects really be curious and judge you, as Piotr Naskrecki says? Or is that standard anthropomorphism?

    I believe it is most likely that insects are like automatons. (Which does not diminish their value in any way.)

    Beautiful photographs.

    1. Of course insects don’t judge us. The text that accompanies the photos in no way represents my views on insets’ perception of the world; it was written by a journalist from the NYT, who picked and chose my words pretty much out of context.

      1. I should have known better! It must be frustrating for scientists to constantly have journalists doing that to them.

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