Guide to
Classification and Sorting
There is nothing worse than trying to find something in a messy room. When we clean it, we are classifying and sorting things according to what they are, maybe without even giving it much thought. For example, we might pick up a shoe and say it belongs in the closet. And, it's a tennis shoe, so we keep it on the right because the left side is for dress shoes. See how it works?
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The classification and sorting of living organisms is called the Science of Taxonomy. It is important in guiding us how we think about the world in which we live. If we are out at a park walking along a pond and someone yells, "Look at that bird," we would probably look up toward the sky or a tree, rather than look into the pond. We do that because we have classified birds in our minds as a creature found in the trees or in the air.
The Science of Taxonomy was first organized by a man named Carl Linnaeus. He came up with a method of classifying things according to characteristics but it wasn't always that way. Allow me to explain.
Science is always changing based on our available knowledge. As we learn more, we understand more clearly. Men like Aristotle, did early classifications based on how animals moved. That's not very complicated. They walked or crawled or rolled, etc. In those early days they didn't know about things like DNA or genetics that we use today.
Mr. Linnaeus developed the modern system of classification that we use today. We call his system Hierarchical Classification because it looks at the different characteristics of living organisms from a broad view going to an increasingly more specific view. In our messy room example, we saw broadly that it was a shoe we were dealing with, then more specifically a tennis shoe. We might further sort it by color or material. Such is the case when classifying or sorting in science.
This is exactly how hierarchical classification works. Carl Linnaeus identified six characteristics by which we classify living organisms. They are kingdom, phylum, class, order, family, genus and species. Each of the characteristics has a set definition to help us make choices as to which the organism best fits. By taking the first letter of each word, an easy way to remember his system is with this sentence. "Kings play cards on fat green stools." Each of these classifications also has sub categories to help us further sort organisms properly. An interesting fact is that Carl was the first scientist to use the term "species"
When it comes to classifying and sorting, scientists have a useful tool to help them make choices based on characteristics. They call it a dichotomous key because it always has two apposing parts. In our shoe example, we might as, "Does it have laces or is it a slip-on?" With a plant, the dichotomous key might be a choice between round leaves or non round or pointed leaves. The important thing about the key is that the two choices are always opposites.
Something else that taxonomy scientists use is called binomial nomenclature. That is a fancy way of saying they use a two part name for each living organism. It is much like determining the kind of shoe, "tennis" shoe but a lot more scientific. It is important to know that the name is always written in Latin, and is italicized and always has two parts. The first part is the genus or descent or type and the second part is the species from the hierarchical classification. It is also important to know that the first name, the genus is always capitalized and the second name, the species, is always written in lowercase letters, like TENNIS shoe.
So next time you get around to cleaning your room, give some thought to the classification and sorting that takes place and also the way we look at the classification and sorting of the living organisms in science that share our world.