Life in the trees: leaf munchers, sap suckers and twig mimics
Insects are sometimes feared and abhorred as they’re small, fast, creepy and can be destructive and dangerous. They can do great damage to our gardens and houseplants (caterpillars, stink bugs), as well as our homes (termites, ants). They build nests on our houses (wasps) and climb the counters in our kitchens (ants). Sometimes they live in our mattresses (bedbugs), bathrooms (moth flies, silverfish) and basements (earwigs).
In fact, insects are kind of infamous; bug eating contests are held on TV shows. Roach motels are named after cockroaches! Some of us have suffered insect stings or bites from ants and wasps. We may have even accidentally eaten an insect or two (many types of beetle larvae can be found in stored grains and spices if not properly sealed).
Insects can, however, be beneficial to us. In some cultures they are actually eaten for their high protein content. Insects spin the silk we use in clothing (ie. silkworms, aka silkmoth caterpillars). If it weren’t for insects, we wouldn’t have honey (honey bees) and many types of food would be missing from the produce section at the grocery store. Apples, avocados, kale, mangoes, citrus, onions and many more, would all be missing from the shelves without pollinators.
Whether you consider them friend or foe, insects are an important part of our environment. Like all living organisms, insects are classified according to the Linnaean system of biological classification. Insects are classified in kingdom Animalia, phylum Arthropoda and class Insecta. There are approximately 30 different orders of insects.
Insects are sometimes called hexapods because adult insects have 6 legs (“hexa” means 6 and “pod” means foot). There are exceptions to this rule, however. Hence many scientists prefer not to use the term hexapod. Each species is assigned a binomial Latin name, which consists of its genus and species. We humans are known as Homo sapiens, while your dog is Canis lupus familiaris (yes, all dogs are one species). In the insect world, Apis mellifera is a honey bee.
In this science project we are going to classify insects only according to their order. We will take advantage of the fact that insects are cold-blooded. The technical term for cold-bloodedness is poikilothermy, which means that insects vary their temperature according to their environment. In contrast, humans are homeotherms because we are able to maintain a constant temperature (about 98.3?F) using our metabolism. After we have collected our insects, we are going to put the insects in a refrigerator to cool down. Once cooled down, they will be less active and we can observe them more easily.
Dichotomous keys are charts used to identify organisms based on characteristics you can observe with your eyes (even if you need help from a magnifying lens to see them!). “Di” means “two” and for each step in the key, there are two choices to choose from - each one describing a particular trait. To use a dichotomous key start at step one. You will have to choose between two different characteristics, choice "a" or "b". Your choice will either give you the name of the insect order, or tell you to proceed to another step in the key. You won’t necessarily go in sequential order. For example, choice a in step 1 may instruct you to go to step 5, while choice b may refer you to step 8. Continue moving from step to step as the key instructs, until you have identified the insect order.
Be careful with biting, stinging or spraying insects! Follow the procedure for handling insects.