March 26, 2013

What Is Taxonomy?

Hi, I’m Emerald Robinson, and in this “What Is” video, we’re going to discuss “Taxonomy.”

Taxonomy is a system that biologists use to group organisms based on similar characteristics. Taxonomy is based on a concept called “homology,” shared characteristics that have been passed down, from a common ancestor.

Although humans have been classifying organisms by various methods since ancient times, Swedish biologist Carolus Linnaeus is considered to be the “father of modern taxonomy”. His most famous work, Systema Naturae, established a system we still used today to determine an organism’s scientific name. This system is called binomial nomenclature.

To understand what makes up the binomial nomenclature, we need to start at the top. Classic biological taxonomy usually places an organism into one of five kingdoms: bacteria, protists, plants, fungi, or animals. Each organism is then classified into the following groups: phylum, class, order, family, genus, and species. It is the genus and species that make up an organism’s scientific name. For example, the scientific name for humans is Homo sapiens, where “Homo” is the genus, and “sapiens” the species.

Sometimes scientists classify organisms using a three “domain” system. The three currently accepted domains are:

Archaea, single-celled microorganisms, that tend to live in extreme environments like very high heat or salt concentration;

Bacteria, which are abundant and live in most habitats on Earth, and

Eukaryotes, any organism made of cells which contain a membrane-bound nucleus.

Although we used to classify organisms based on characteristics that could be seen by the naked eye or under a microscope, today we commonly rely on analyzing an organism’s DNA instead.

Scientists will continue to use these means to classify the approximately 15,000 new species that are identified each year.

Share on Linkedin Share on Google+