Animals are multicellular, meaning that they are made up of a body (the animal) and an exoskeleton (the skeleton). Animals breathe air, eat food, can reproduce through sexual reproduction, move about on land and water, can secrete waste material and get energy from the sun and other external sources. In some sense, all animals are alive.
The word “animal” comes from the Greek word arachnidos, meaning “not a bird.” Birds and mammals are classed as vertebrates, while insects, crustaceans, fish, amphibians, and worms are classed as invertebrates. Therefore, in this article, when I use the term “animal,” I mean something very different from what most people think.
To classify animals properly, you must understand both their anatomy and physiology, as well as what goes on in their minds and bodies. People think that animal research is just an animal going around and munching its way through plants, and this assumption is false. Animals use their minds and bodies to hunt, scavenge for food, fight, flee from danger, make nests, and so on. Many animals are classified by what part of the body they use to do these things, rather than by what kind of animal they are. Humans are classified by species, because our bodies are combinations of all those types of animals we mentioned.
The nerves and the brain of animals are very similar to ours, and many similarities can be found between the nervous system and the functions of animals and humans. The nerve system is complex, but you don’t need an expert to know this. Animals use the nerves and the brain for similar purposes, and this allows them to adapt well to their environment. This is one of the most important points about animal research: adaptation. Animals can change, but they do so very slowly, which makes it very easy for a scientist to study their behavior in a controlled environment.
Insects are another great example of adaptation. Most insects have evolved over time, and some, like the tiger moth, have become so well adapted to their environments that they’ve been able to fly around the world with only a wingspan the size of a pin head. The eidolon or sea slug is another good example; it has evolved into such a tiny, streamlined creature that scientists have trouble even recognizing it. They have evolved into such bizarre looking creatures that they’ve become known simply as “sea slugs”. There are more examples of animals evolving over time, but there are some that are really bizarre.
We could talk about animal biotechnology for hours, but at the end of the day, it’s really animals that we should be studying the behavior of. We’re interested in animals that can adapt and overcome the obstacles that face them in order to survive, which means that the kinds of animals that we find in the Biological Kingdom Animalia are the best specimens of these types of animals. It’s interesting to observe their incredible adaptability and the amazing changes that have taken place within the animal kingdom over the course of history, so it’s no wonder that we use these animals as subjects for biological study.