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.