As a Conservation Education Presenter, we get the wonderful opportunity to talk about a wide range of animals. I’ve been able to chat with Guests about the Siamangs, Gibbons, Anteater, Babirusa, Muntjac, Macaws, and Crocodile, but some of the more not-so-obvious members of the animal kingdom we work with are the invertebrates.
Okay, so what’s an invertebrate? Basically, it’s any animal without a backbone. Tarantulas, spiders, scorpions, bees, butterflies, millipedes, centipedes, cockroaches, etc. all fit into this category. With over one million species of animals in this world, about 95% of them are invertebrates, and 90% of the total weight of all animal species is made up of invertebrates. How amazing is that!?
Some types of invertebrates can make peoples skin crawl, but without these guys, our world would be a much less enjoyable place.
Take cockroaches and millipedes for example; gross bugs, right? Wrong. These guys are awesome recyclers! They eat all the dead plant material that falls to the ground and make awesome fertilizers for our soils. Without these little critters, we’d have soils lacking in minerals and nutrients, not to mention a ton of organic material built up, such as dead trees and rotten fruit. While it may not be preferable to have cockroaches and millipedes as household visitors, they really do have their purpose and role in the environment (and can really help you out in your garden).
Madagascar Hissing Cockroaches are pretty unique too. They don’t have wings, so instead, they use a hissing noise to defend themselves. If you look closely at their backs, you can see little black dots lining the edges. These black dots are called spiracles, and are actually a part of the cockroach’s respiratory system, as they inhale and exhale through them. They also use the spiracles to make their hissing sound as they exhale, which make them sound much more ferocious than they actually are and is a great line of defense. Males also use the hissing sound as a mode of communication in mating as well as aggressive encounters with other males. They’re really quite interesting creatures.
Tarantulas are another amazing animal, and also play an important role in our ecosystem. They help us out by eating lots of bugs and keeping the insect population down. Without these so-called “creepy-crawlies” we’d have a lot more mosquitos and other insects buzzing around. So the next time you see a spider or tarantula in your house, maybe you could slide a piece of paper under it, put a cup on top, and let it go outside, and let it eat up all those mosquitos that we don’t appreciate so much.
Often thought to be deadly to humans, tarantulas are actually not poisonous. They do have venom, but it is designed to digest insects and other animals smaller than itself. Tarantulas don’t have digestive enzymes like we do in our stomachs. They have a sucking stomach, so they need to digest their foods before they enter their bodies. This is done using the venom. I think of it as an “outside” stomach. If a tarantula would bite you, it would probably feel no worse than a bee sting. Your skin may have a slight reaction, but unless you’re allergic, it should not be life-threatening.
If you look closely at their bodies, tarantulas are covered in little hairs. These hairs are extremely sensitive, and used to detect movement and also as a defense mechanism. They can brush off these special urticating hairs with their back legs, making them float into the air. If these hairs come in contact with the another animal, they are extremely irritating.
Because tarantulas and other invertebrates don’t have a backbone, their skeletons are actually on the outside of their bodies. This is called an exoskeleton, and the invertebrate must molt, or shed, this exoskeleton every time it grows.
The tarantula that produced this molt is probably still alive yet, just larger. Looking at the picture, you can see small holes in the middle of the body. These holes are where the tarantula puled its legs out of the molt, just like you would slide your fingers out of a glove. Below that are four white areas, which is where the lungs would have been. On the head (which is the little brown piece next to the molt) you can see eight tiny little white dots. These are actually the tarantulas eyes. The eight eyes help us to identify a tarantula versus a spider. Tarantulas will always have eight, while a spider can have multiples of two eyes (for example, six and ten are possibilities). Also, a tarantulas pedipalps (the things that look like fangs) go up and down, while a spiders go side to side.
The final invertebrate I’ll introduce you to today, are the Lubber Grasshoppers. They’re native to Florida and can be found in the south-eastern portion of the United States.
They change colors throughout their life-cycle, but are generally brightly patterned. These colors indicate to predators that the Lubbers actually taste really bad and are somewhat toxic. They’ve actually been known to make animals sick and, according to the University of Florida Institute of Food and Agricultural Sciences, even lead to their demise. The Lubber Grasshoppers can also excrete an irritating foamy spray if their coloration isn’t enough of a defense signal to predators.
Lubbers have wings, but they can’t actually fly. They can hop, but they’re really quite docile, so if you find them munching on your prize flowers, you can simply pick them up and move them somewhere else. Though you may not be excited to have them eating your favorite plant, they do play a role similar to millipedes, in that they fertilize the plant soil with their nutritious plant-poo.
Though you may still not thrill at the sight of some of these invertebrates, I hope you think twice before you squash one. These guys are really important little critters, and help keep our ecosystem in balance. Without them, our world would be a much different and less enjoyable place. If you find one where you don’t what them to be, why not let them do their jobs, and simply move them? Every animal has its role, we might just have to do a little digging to find out what it is.
If you have any questions or would like to know more about invertebrates, let me know in the comments!