Stick insects, stick-bugs, walking sticks, bug sticks, ghost insects, or phasmids. These are all common names for stick insects. I decided to lump all the stick insects together as an Awesome Animal simply because I am so impressed by their stunning variety of colors, shapes, and sizes, most of which allow them to become almost invisible against their surroundings.
What the heck is a Stick Insect?
Phasmids are an order of about 3,000 species of insects that live mostly in the tropics, although a few species live in temperate areas, including here in the midwest United States. In Missouri we have two species, one of which happens to be the largest insect in North America, the Giant Walking Stick, which is seven inches long (some tropical species are much larger).
Here is a giant walking stick in Missouri:
Amazing Facts about Stick Insects
When it comes to stick insects, we really need to talk about camouflage. Being invisible is a stick bug's super power, and some of the species have taken this camouflage thing to a whole new level. In fact, the name Phasmid comes from the Ancient Greek phasma, which refers to a phantom, an apparition, or a ghost.
Stick insects spend most of their time in trees, munching on leaves. That may seem like a boring life, but being a bug in a tree is extremely dangerous. Why? Because trees are teeming with predators, including birds, monkeys and other primates, reptiles, spiders, small mammals, and even other insects. And don't forget about bats. Stick insects are too slow to run from predators. Most species don't have wings, so they can't fly from predators. They can't run, they can't fly, but they can sure hide!
When a predator comes near, stick insects try to look like part of the tree. Usually this works, but even if it doesn't, and the bird grabs the insect by one of its legs, the leg will pop off, the stick insect will crawl away (if it's lucky), and eventually it will regenerate the lost leg.
The Australian prickly stick insect below is an example of how extreme the adaptation for camouflage can be.
In case you need further convincing, the photo below shows three individuals of the same species (Phyllium westwoodii). This species is highly adapted to resemble the leaves on the trees on which they feed. This species lives in China and the surrounding areas.
Another example is the moss mimic stick insect (see below). This one is adapted to look very much like the moss that grows on the trees where the stick insect feeds.
Not only can stick insects look just like their surroundings, many of them apparently move just like their surroundings. Stick insects actually use their legs to sway back and forth, making them look like a twig swaying in the breeze.
Check out this video of stick insects, showing examples of how they can move.
Well... as I said, when stick insects feel threatened, they often start swaying back and forth. Not surprisingly, this has resulted in countless stick insect dancing videos posted online.
Here is a typical example.
Enough of that silliness!
I will point out that camouflage, swaying, and detaching their legs are not the only ways stick insects avoid being eaten. The different species have developed an impressive array of additional defenses. For example, some types have sharp spines. Some expel noxious odors from special noxious odor glands. Some have yucky-tasting chemicals in their blood, which they can squirt out through seams in their exoskeleton. Some have the ability to startle predators by making a loud noise. Some curl up their tail to look like a scorpion. Some even have brightly colored wings they can display to confuse a predator. Finally, some are so large that they are intimidating to smaller predators.
Like this impressive specimen from Malaysia:
Some stick insects, in fact, are among the longest insects in the world. Below is another species from Malaysia, Phobaeticus serratipes. One female of this species, with her legs extended, was 22 inches (55 cm) long. This is simply too large for smaller predators to handle.
One more tidbit of information. As you have no doubt already surmised, stick insects are really good at avoiding predators. Well, not only do they protect themselves from being gobbled up, they also have evolved some impressive ways to prevent their eggs from being snarfed up. Stick insects lay hundreds of eggs. Laying all these eggs in one spot can be risky (it's the old "don't put all your eggs in one basket" thing). So, some species fling their eggs to the ground one at a time, thus spreading them out. Some find discreet hiding spots to lay their eggs, and some even glue their eggs to the undersides of leaves.
However, my favorite strategy is even more impressive. Some stick insects have developed an amazing relationship with ants. Yep... ants. The stick insects attach fatty capsules to the surfaces of their eggs. These fatty bundles are tasty and nutritious. So, the ants seek out the unhatched eggs and carry them to their nests below ground. The ants get to eat the fatty capsules, and the eggs get to develop in a safe place. When the eggs hatch, the young stick insects simply leave the ant nest to start their new life!
So, the Stick Insect deserves a place in the A.P.E.H.O.F.
(Animal Par Excellence Hall of Fame).
FUN FACT: The adjective par excellence means "preeminent," or "being of the best kind." Interestingly, this is an adjective that is usually placed after the noun it describes. Example: "Stan is a novelist par excellence." Or, "Across Horizons is a science fiction series par excllence." Par excellence is a French phrase, but it comes from the Latin per excellentiam, which means "by way of excellence." The first known use of par excellence was way back in 1695, so it's been around for a while.
So, par excellence is another way to say awesome!
Missouri Giant Walking Stick - Jim Rathert/Missouri Department of Conservation
Australian giant prickly stick insect - DepositPhotos
Three leafy stick insects - DepositPhotos
Moss mimic stick insect - Frank Vassen/Wikimedia Commons
Large stick insect from Malaysia - DepositPhotos
Giant Stick insect on man - Bernard DUPONT/Wikimedia Commons
Everyone needs a creative outlet. That's why I write.