There are 8 groups of classification:
Animals in each group share similar characteristics. Each subsequent group continues to add more specific characteristics on top of the existing ones. Thus, eliminating animals who do not meet the criteria, until you are left with one animal!
To better understand each group and their characteristics, let us use an example. Below, the picture illustrates how an American black bear is classified through all 8 groups. Animals (and other things, such as plants) use a universal classification system.
Latin words are used to describe the shared characteristics between animals in a group, and to assign a scientific name to an animal. Therefore, two biologists from opposite ends of the world would both know that ursus americanus (scientific name) means American black bear (in their respective language).
1. Beginning with domain, we know all animals (and plants) in the group share a characteristic. What is it? Well, the American black bear belongs to the Eukarya domain, which means all organisms in the domain have cells with membrane-bound organelles.
2. A bear is an animal, thus it belongs to the kingdom Animalia (animal).
3. Its phylum is Chordata, which means vertebrates (animals with backbones).
4. Since mother bears supply their cubs with milk to survive, they fall into the class Mammalia (mammals).
5. Order depends on the animal’s diet. Bears are meat-eaters, which is the order Carnivora (carnivores).
6. Family for bears is Ursidae, meaning bears.
7. Genus means subfamily. Thus, the American black bear belongs to Ursus, which is a particular subfamily of Ursidae.
8. Finally, the species is the scientific name for American black bear, which is Ursus americanus.
Three subgroups of classification not mentioned, nor shown, are suborder, subfamily, and subspecies. Suborder and subfamily are an additional grouping of animals with the same characteristics. Either one will be used in classification if an animal has different characteristics that lie between the animal’s order and family, family and genus, or both!
A subspecies is a type of species, but with different traits. If there were subspecies of Ursus americanus, that subspecies would have different traits than American black bears.
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