All About Bugs

If you want to observe or study bugs, it helps to know a bit more about them first. The term "bug" is generic and typically refers to a wide assortment of small, creepy crawly critters. These might be better called arthropods. Arthropods are invertebrate organisms that have an external skeleton (compared to an internal one), a segmented body, and jointed appendages such as legs and antennae.

This large group includes insects, crustaceans, spiders, centipedes, millipedes, and scorpions among others. Together they are the most successful, largest and most diverse group of animals on the planet, representing nearly 85% of all known animal species.

Insects are by far the most familiar and frequently encountered arthropods. They are also incredibly diverse, with over 1 million known species. The vast majority of species on Earth that are yet to be described are likely insects and other arthropods. In fact, scientists conservatively estimate that the total number of insects could exceed 8 million when all are eventually discovered. While the vast majority of that amazing diversity exists in the tropics, there are well over 150,000 species of insects in the United States and Canada alone. They are also incredibly abundant. Although it may sound crazy, there are about 1.5 billion insects on Earth for every human being.

Entomology is the study of insects. It is a wide scientific field that makes contributions to biology, agriculture, chemistry, human and animal health, conservation, the environment, medicine, and even criminal investigation (forensics). Entomologists work in laboratories and in the field. They identify new species and uncover evolutionary relationships between species. They help ensure safe and sustainable food production, combat plant, animal and human diseases, work to prevent pest damage to homes, landscapes and the environment, and many other things.

But you don't have to have a college degree to enjoy or study insects. Anyone can learn about them, and even collect valuable scientific information or make new discoveries. Today, there are also many opportunities for citizen scientists, members of the general public who help collect and analyze data, to contribute. No matter if you're interested in butterflies, ants, ladybugs, bees or even earthworms, there are a great many citizen science programs available.

Of course, the first step is probably just exploring and getting to know the many different types of bugs that are right outside your door.

An Insect's Body

All insects share several common features. Unlike humans, other mammals, birds, reptiles and amphibians, insects lack an internal skeleton. Instead, they have a hard (or generally hard) outer covering called an exoskeleton. It serves several functions including protection and support. Like armor, it helps guard the insect's body from damage and water loss (desiccation). The exoskeleton also provides support for muscle attachment which enables movement.

An insect's body is divided into three main sections: the head, thorax, and abdomen. An insect's head has two compound eyes, two segmented antennae, and mouthparts. The rounded and often large compound eyes are made up of hundreds of tiny individual lenses. Working together, they provide a single, somewhat grainy (or pixelated) image and give insects rather good vision, especially for both distance and motion.

Above the eyes are two segmented antennae. They contain sensory structures that help with smell, taste, touch, and orientation.

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Excerpted from Insects and Bugs for Kids: An Introduction to Entomology by Jaret C. Daniels
All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.