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Archive - March 2022

What is Taxonomy?
Taxonomy is the science or technique of classification.

In biology, it is the science concerned with the description, identification, naming and classification of organisms.

The work of classifying organisms is done by scientists called taxonomists. Taxonomists separate types of organisms into a ranking system of more and more specific groupings.

Classification groupings can be confusing, so we are going to start with the seven main categories: kingdom, phylum, class, order, family, genus and species.

The ranking system allows taxonomists to group organisms based on their characteristics and evolutionary relationships. For instance, organisms in a single “order” are more closely related to each other than to organisms in any other “order.” Within an order there will be one or more “family” groups. The organisms in a single “family” are more closely related to each other than to organisms in any other “family.” The number of types of organisms in each category gets smaller as you progress from kingdom through species. The genus and species categories together provide the scientific name of a single type of organism.

Figuring out how an organism should be classified is not easy. Scientists look for structural and genetic similarities among organisms that they classify together but differences and similarities among living things are not always clear-cut. Taxonomists sometimes disagree about the classification of types of organisms. As new information becomes available, they often revise where an organism is placed within the classification system.

A kingdom is a broad classification category that includes organisms with common ancestry and other similarities. In current taxonomy, there are six kingdoms: Eubacteria; Archaebacteria; Protozoa; Fungi; Plantae; and Animalia. Not all scientists agree with these categories, and they are subject to change as more information becomes available.

You may recognize three of these kingdom names and the types of organisms classified in them, but the other three kingdoms might be new to you.

Kingdom: Eubacteria
The eubacteria group contains most of the familiar types of bacteria. These organisms are single-celled and lack a nucleus and organelles. Some of them obtain nutrients by absorption of materials from living or dead organisms; some make their own food; and some decompose dead organisms for food.

Kingdom: Archaebacteria
Archaebacteria are associated with extreme habitats, such as hot springs and thermal vents on the ocean floor. Like the eubacteria, they do not have a nucleus or organelles, but genetically they are structured like the eukaryotes, those organisms that do have a nucleus. This very ancient group may be the ancestors to multicellular organisms.

Kingdom: Protozoa
The Kingdom Protozoa consists of single-celled organisms. Protists have a nucleus as well as other cell structures that perform specific jobs. Protists include certain types of algae, slime molds, amoebas and diatoms.

Kingdom: Fungi
Mushrooms, molds, yeasts and mildews are examples of members of the Kingdom Fungi. Most fungi are made of many cells. They are not able to make their own food. Some are saprobes. Some are parasites. Some are mycorrhizal. Many are combinations of these lifestyles.

Kingdom: Plante
The Kingdom Plantae includes the plants. Most plants produce their own food energy through photosynthesis - a chemical reaction involving sunlight, carbon dioxide and water in the presence of chlorophyll.

Kingdom: Animalia
The Kingdom Animalia consists of vertebrates, like mammals, birds, reptiles, amphibians, fishes, as well as invertebrates like insects, spiders and a whole host of other animals. Most animals are multicellular organisms that have specialized tissues, organs and organ systems. Unlike plants, animals cannot make their own food, and their cells don’t have cell walls. They usually are able to move at least in some stage of their life.