1.)As an introduction to the activity, discuss classification in general. Ask students what we mean by classification and why we classify things. For example, why do we classify certain objects as tools, others as food and so on? Establish that classification – the arrangement of objects, ideas,
or information into groups – makes things easy to find, identify, talk about, and study.
2.)As background information, let students know that, beginning in ancient times, scientists tried to develop a system of classifying animals and plants. The system we use today was developed by the Swedish naturalist Carolus Linnaeus (1707-1778), who separated animals and plants
according to certain physical similarities and gave identifying names to each species.
3.)Go on to explain that Linnaeus’s system classified plants and animals on seven levels, using Latin and Greek words. On the chalkboard, reproduce the example below, which shows how a brown squirrel is classified: Kingdom (Animalia, or “animal”); Phylum (Chordata, or “has a backbone”); Class (Mammalia, or “ has a backbone and nurses its young”); Order (Rodentia, or “has a backbone, nurses its young, has long, sharp front teeth”); Family (Scuridae, or “has a backbone, nurses its young, has long, sharp front teeth, and has a bushy tail”); Genus (Tamiasciurus, or “has a backbone, nurses its young, has long, sharp front teeth, has a bushy tail, and climbs trees”); Species (hudsonicus, or “has a backbone, nurses its young, has long, sharp front teeth, has a bushy tail, climbs trees, has brown fur on its back and white fur on its underparts”).
4.)Discuss the example with the class, bringing out the idea that each subsequent level of classification eliminates animals that could be included in the previous level. To make this point, have students give examples of several mammals (the class Mammalia) and then tell which ones are eliminated by the description of rodents (the order Rodentia), have them name several rodents and then tell which rodents are eliminated by the description of the genus Tamiasciurus; and so on.
5.)Tell students that it is not necessary to go through the entire seven level classification system to identify a plant or animal. Just two names – the genus and species names – are sufficient. Thus, the scientific name for the red squirrel is Tamiasciurus hudsonicus. Because two names are used, the system is known as the binomial (two names) system of nomenclature (naming).
6.)Tell students that since Linnaeus' time, as scientists discovered new organisms and changed their ideas about what characteristics are important in classifying organisms, the classification system has changed. Today's classification system contains five kingdoms: Monera
(prokaryotes), Protista (single-celled eukaryotes), Fungi (molds and yeasts), Plantae (plants), and Animalia (animals). This five-kingdom classification system was suggested by R.H. Whittaker in 1969. In addition, a newer system even than Whittaker's has instituted a level above kingdom--the domain. Under this newer system, life consists of three domains--Bacteria, Archaea, and Eukarya (which contains both the plant and animal kingdoms as well as the fungi kingdom and the protista kingdom (mold and algae).
7.)Have students choose one or more of the animal pictures. Have students find the genus and species names of their animals using their biology books, encyclopedias, encyclopedias on CD-ROM, or classroom textbooks, or search online.
8.)Instruct each student to list on the chalkboard three or four scientific names he or she has found and the common names of the animals they identify.
9.)Divide the class into groups and have them devise their own systems of classifying everyday objects around the room. Students should use at least four levels of classification, but they may use as many more levels as they find necessary. They should end up with a two-part name for each of several objects in the room. Advise students to use Linnaeus’s system as a model, starting out with one classification level that divides all the objects in the room into two major categories. For example, the two “phyla” could be “natural” (made of natural materials) and “artificial” (made of artificial materials); or “useful” and “decorative.” Two major categories combined should include all objects in the room, and the final “genus” and “species” names should exclude all objects but the one being identified. (Students should use descriptive phrases rather than single words, and, of course, would not be required to use Greek or Latin terms.)
10.)If time permits, allow the students computer time to make a slideshow presentation illustrating the new classification system, inserting actual pictures of various objects taken with a digital camera. Let the groups present their new systems to the class.