6. Stick insects put up a good fight, but they do it highly creatively and only on the defensive. When threatened, rather than fight back tooth and nail (they couldn’t, anyway, as they aren’t in possession of nails, per se), they can voluntarily produce a substance from their mouths that’s bitter to a predatory palate, putting their would-be consumer off the meal entirely. They can also summon a secretion from their bodily joints, a smelly potion made of hemolymph, with the intention of suppressing the attacker’s appetite. Some species can repurpose the spines on their legs that they use for climbing, kind of like anatomical crampons, as thorns to prick their enemies, and another can emit a kind of noxious mist to confound the senses of the beast compelled by hunger to trespass against it.
TAKEAWAY: These slender specimen of the animal kingdom may look delicate, but they do not go gentle into the mouths (or beaks) of their predators. In the words of the Bard, “Though she be but little, she is fierce.”
7. Remember those stick insect eggs that resemble seeds? Well, those eggs are built even more cleverly than just that. In an elaborate trick of mimicry, each egg is appended with a small, lipid-rich knob called a capitulum, resembling the elaiosome on castor oil plant seeds (and others), which provides a food source for many species of ant. When an ant catches wind of the seed-like end of a stick insect egg with its fatty fixture, it will ferret the egg back to its nest to consume the capitulum (or feed it to the kids, er, larvae). Frequently the eggs are left intact after this, and the ants toss them onto their compost, where the stick insect infants emerge. These nymphs look rather like ants themselves, so they’re able to escape the warren and climb incognito out and onto, hopefully, a tasty plant. Stick insect eggs even have an armor of calcium oxalate which preserves them from avian gastric acid; that’s right, an egg can pass unscathed all the way through the digestive system of a bird and hatch where it lands, having hitched a flight to a new area in which the species can further diversify.
TAKEAWAY: This insect has taken every opportunity evolution has offered it, it seems, in an effort to ensure the survival of its kind. The only threat I could imagine to its perpetuation on this earth is if humans ever take it upon themselves to appropriate some kind of utility from these animals. Nothing is as good at precipitating extinction as that mercenary species we call homo sapiens. As long as we leave well enough alone, the stick insect’s enterprising evolution ensures enduring life potential for countless future generations.
8. It’s no secret that hiding in plain sight is a special trick indeed. Anyone who might claim that Darwin didn’t have his finches in a row would have a hard time explaining camouflage in nature, I imagine. Well, stick insects take it to a new level altogether. They have brightly-colored wings that they keep all folded up, collapsed in on themselves, umbrella-like, hiding the brightness. If an insect senses that a predator has spotted it despite its camouflage, it can flash open those wings to confuse the onlooker and hope to escape notice once the threatening beast has refocused its vision. It’s the animal kingdom equivalent of someone looking at one of those encrypted images in a “Magic Eye” book, but as soon as he’s glimpsed the hidden picture and is tracing a bead on its contours, someone flicks a coral scarf across the page, essentially snapping the visual discovery back into obscurity.
TAKEAWAY: If you’ve seen “The Usual Suspects”, you know what I mean when I say that stick insects know how to play the Kaiser Söze card. Is that a tasty tidbit you see on that piece of treebark, you bloodthirsty rodent? ::wingflash:: Nah, just smoke in mirrors. They keep this hidden weapon, the power of bewilderment, under their vests, as it were, and know to unfold the living color in yet another ploy to escape danger. “Now you see me,” they seem to say, “and now you don’t.” No holds barred for life and limb.
9. Not that this next trick is one played exclusively by stick bugs, but their last-ditch effort upon earning the notice of an insectivore is to drop dead, or appear to. Thanatosis, the defense mechanism employed frequently by animals in that moment of abject distress in which they fear for their lives, allows them to assume the posture of posthumousness. For stick insects, the objective of playing dead is twofold; if they fall from a leaf to the ground, for example, perhaps they’ll be concealed by grass or whatever substrate might make them difficult to spot. Another incentive of this method is that to mimic lifelessness is also to assume the posture of unpalatability. Usually insect predators prefer their meals to be alive at the time of consumption, so encountering dead (or seemingly dead) prey doesn’t enliven the appetite in the same way as a hale and hearty specimen would.
TAKEAWAY: Imagine you’re an innocent cookie just hanging out in the pantry, minding your own business, and a hungry kid comes hunting for a tasty snack. If you could, in that moment, summon the perception of being stale or rotten, would the kid pass over you in favor of something fresh? Almost certainly. I’m not saying I wish I could suddenly appear to not be alive in my own habitat, but wouldn’t it be nice once in a while to appear uninteresting, even invisible, just temporarily? For instance, if these kids couldn’t sense my life force wherever I am in the house, would they resist constantly asking me things, like to help them find the sock that’s on their left foot or a burning question like this one I got the other day: “What if people didn’t have fingernails?” It would feel like such respite to tuck up under an invisibility cloak from time to time, just so our presence wouldn’t be incessantly noticed and capitalized upon. How wondrous, indeed, to be ignored! But, then again, I imagine that’s what it’s like to live with teenagers.