The scientific classification of animals, known as Taxonomy, is designed to classify the millions of animals into categories based on shared traits to better understand how animals are related to each other. Swedish naturalist Carolus Linnaeus designed the system of classifying organisms in the 18th century.
Towards the end of the 17th century naturalists had started to notice that many animals appeared to have relatives and animals that shared similar traits. Linnaeus set up the classification system called the Linnaean system, which is still in use today. The seven mandatory taxonomic ranks are as follows:
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
Life, Domain and sub-family, sub-species etc are also used, but the Kingdom, Phylum, Class, Order, Family, Genus, Species is what must be used. Linnaeus divided the animal kingdom into six classes in the mid 1700s and these names are still recognizable today. These were:
- Class 1: Mammalia
- Class 2: Aves (birds)
- Class 3: Amphibia
- Class 4: Pisces (fish)
- Class 5: Insecta
- Class 6: Vermus (worms)
- Class 7: Reptila
Each species is given a two-word scientific name derived from Latin and Greek words. This two-word classification is called binomial nomenclature and is always written in italics, the first word beginning with a capital letter, the second beginning with lowercase. An example of this naming is Panthera leo. This is a scientific name for lion. Panthera is the genus name and leo is the species name. The full classification for lion is:
- Kingdom: Animalia
- Phylum: Chordata (animals with backbones)
- Class: Mammalia
- Order: Carnivora
- Family: Felidae (the cat family)
- Genus: Panthera
- Species: P.leo
The Linnaeus classification allows us to see how animals (and plants, etc) are related to each other. For example dogs and other similar predators belong to the order Carnivora just like cats do.
The phylum Chordata encompasses all vertebrates (the animals with backbones) such as mammals, birds, fish, amphibians and reptiles. Originally, Linnaeus and other naturalists classified animals on looks alone, and while this worked most of the time, it wasn’t foolproof. Early scientists thought that whales and dolphins were types of fish but we now know they are marine mammals.
Now classification is done by a study known as cladistics, which uses genetic analysis to determine where animals fit in with each other. Animals are grouped according to how they evolved and the divisions show common traits. Traits that mammals share include having hair (even if it’s not clearly visible), the females have mammary glands, mammals are warm blooded and they breathe via lungs.
As scientists improve the classification system, our understanding of all living organisms and evolution of life will improve.
Roberta Goli - Roberta has a Bachelor of Science Degree (Zoology), has worked with animals for over 10 years and enjoys writing short stories and flash ...
