|
CLASSIFICATION OF ORGANISMS | |||||
| The Greek philosopher Aristotle (384-322 BC) grouped life forms as either plant or animal. Microscopic organisms were unknown. | |||||
| Plants | Animals | ||||
| Plants | Animals | ||||
| Fungi | |||||
| In 1735 Swedish naturalist Carolus Linnaeus formalized the use of two Latin names to identify each organism, a system called binomial nomenclature. He grouped closely related organisms and introduced the modern classification groups: kingdom, phylum, class, order, family, genus, and species. Single-celled organisms were observed but not classified. | |||||
| Kingdom | Plantae | Animalia | |||
| Organisms | Plants | Animals | |||
| Fungi | |||||
| In 1866 German biologist Ernst Haeckel proposed a third kingdom, Protista, to include all single-celled organisms. Some taxonomists also placed simple multicellular organisms, such as seaweeds, in Kingdom Protista. Bacteria, which lack nuclei, were placed in a separate group within Protista called Monera. | |||||
| Kingdom | Protista | Plantae | Animalia | ||
| Organisms | All single-celled organisms, such as amoebas and diatoms, and sometimes seaweeds. | Plants | Animals |
| |
| In 1938 American biologist Herbert Copeland proposed a fourth kingdom, Monera, to include only bacteria. This was the first classification proposal to separate organisms without nuclei, called prokaryotes, from organisms with nuclei, called eukaryotes, at the kingdom level. | |||||
| Prokaryotes |
Eukaryotes | ||||
| Kingdom | Monera (Prokaryote) | Protista | Plantae | Animalia | |
| Organisms | Bacteria | Amoebas, diatoms, and other single-celled eukaryotes, and sometimes seaweeds | Plants, fungi | Animals | |
| In 1957 American biologist Robert H. Whittaker proposed a fifth kingdom, Fungi, based on fungi's unique structure and method of obtaining food. Fungi do not ingest food as animals do, nor do they make their own food, as plants do; rather, they secrete digestive enzymes around their food and then absorb it into their cells. | |||||
| Protista |
Eukaryotes | ||||
| Kingdom | Monera (Prokaryote) | Protista | Fungi | Plantae | Animalia |
| Organisms | Bacteria | Amoebas, diatoms, and other single-celled eukaryotes, and sometimes seaweeds | Multi-cellular, filamentous organisms that absorb food | Multi-cellular organisms that obtain food through photo-synthesis | Multi-cellular organisms that ingest food |
Carolus Linnaeus was a Swedish botanist who develop binomial nomenclature which is designed to have the same scientific name for a given organisms worldwide regardless of language. Much of his naming has been altered by later discoveries, but his basic principles are still followed.
Why is Latin used for scientific naming: Unchanging, no nationalism, understood (at the time) by almost all scientists, and has great descriptive power. By this means an animal has the same scientific name regardless of the language (spelled same, pronounced same).
Mandatory ranks of animal classification (taxonomy): species, genus, family, order, class, phylum, kingdom. Define species and then each of the ranks in relation to it. Discuss chromosome numbers and species. Examples: Human 46, sheep 54, alligator 32, armadillo 64, bat 44, camel 70, cat 38, dog 78, donkey 62, and horse 64 (show why donkey & horse are not same species although they can produce offspring).
|
Examples of Taxonomic Categories | |||
| Rank | Human | Gorilla | Leopard Frog |
| Kingdom | Animalia | Animalia | Animalia |
| Phylum | Chordata | Chordata | Chordata |
| Class | Mammalia | Mammalia | Amphibia |
| Order | Primates | Primates | Anura |
| Family | Hominidae | Pongidae | Ranidae |
| Genus | Homo | Gorilla | Rana |
| Species | sapiens | gorilla | pipens |
Rules for writing scientific names: Genus capitalized, species lower case, italics or underlined (to indicate foreign phrase), sometime followed by the name of the person who assigned the name.
Examples of scientific names: Felix leo (lion), Homo sapiens (human), Amoeba proteus, Rana pipens (leopard frog); Lumbricus terrestris (earthworm); & as many more as there are species of animals. How many total species are there-nobody knows but well over 1,000,000 and probably twice that.
This is far superior to the use of common names which vary for the same animal even in the same country, and certainly among the many human languages.