Taxonomy - Chap 14 and 19 Taxonomy is the science of naming and classifying organisms The system used by biologists is called the Linnnaean System. Carl Linnaeus was a Swedish biologist in the mid-1700s He popularized a system of grouping organisms according to like characteristics and giving each group a specific name.

Taxonomy The most important part of this system was the use of binomial nomenclature Binomial nomenclature is the use of a two word name to identify individual species, i.e. Anampses chrysocephalus is the Psychedelic Wrasse. Many of the species Linnaeus named in 1753 still have the two-part names he gave them.

Taxonomy The first part of the name is the genus. A genus is a group of closely related species. Most hybrids are between two species in the same genus. The genus is always capitalized. The second part of the name is the species name. A species is a group of organisms that are capable of interbreeding and can produce fertile offspring of both sexes. The species name is never capitalized.

Taxonomy Saccopharynx harrisoni Genus : Saccopharynx Species : harrisoni Other species in the same genus include berteli, hjorti, flagellum and thalassa

Common Name vs. Scientific Name Scientific name: Naso lituratus Common Names: Orangespine Unicornfish Orangespine Tang Naso Tang Orange Lipstick Surgeonfish Umaumalei (Hawaiian name)

Higher Levels of Classification There are 8 levels of classification. Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species Each level of classification is based on characteristics that are shared by all organisms in that level. A handy mnemonic: Dumb Kids Play Checkers On Freeways Get Smashed. Danish Kings Play Chess On Fat Green Stools. Daringly Keeping Precious Creatures Organized For Grumpy Scientists

A Sample Organism

The American Lobster Domain: Eukarya - made of eukaryotic cells Kingdom: Animalia – multicellular heterotroph whose cells lack cell walls Phylum: Arthropoda – jointed appendages, exoskeleton, and a segmented body Subphylum: Crustacea – Use gills to breathe, have antennae Class: Malacostraca – 3 body segments with 5 head segments, 8 thorax segments and 6 abdomen segments Order: Decapoda – ten legs Family: Nephropidae – clawed lobsters Genus: Homarus – Atlantic clawed lobsters Species: americanus – American Lobster

Domains There are three domains. Archaea – Unicellular prokaryotes, often found in harsh environments Bacteria – Unicellular prokaryotes, found everywhere Eukarya – Uni or Multicellular organisms Most non-microscopic life is included in this domain.

Prokaryotic vs. Eukaryotic All cells can be divided into two types Prokaryotic cells don’t have a nucleus. All prokaryotes are unicellular. Eukaryotic cells have a nucleus Eukaryotes can be either unicellular or multicellular.

Archaea Contains one kingdom, Archaebacteria Unicellular prokaryotes Archaebacteria are often found in extreme environments, such as hot springs or salty lakes. Thermophiles live in very hot places, up to 106 degrees celsius! Acidophiles live in water as acidic as sulfuric acid! However, some live in the same environments bacteria do.

Bacteria Contains one kingdom, Bacteria The most abundant organisms on earth! Unicellular prokaryotes Some live without oxygen, called anaerobes. Some use inorganic compounds such as ammonia or methane to make energy.

Eukarya The domain Eukarya is made of four kingdoms. Protista, Fungi, Plantae, and Animalia All organisms in the domain Eukarya are eukaryotes. Most are multicellular, some are unicellular. Some are microscopic, but most can be seen with the naked eye. Eukarya is the only domain that has organisms that undergo true sexual reproduction.

Protista The “garbage” kingdom If an organism isn’t a plant, an animal or a fungus, it’s a protist. Many are unicellular, in fact, all unicellular eukaryotes (except yeasts) are included in kingdom Protista. Because they are a “garbage” kingdom, they have diverse characteristics. Notable types of protists: Algaes and kelps Diatoms Dinoflagellates Slime Molds

Protista

Fungi Fungi include mushrooms, molds and yeasts. All fungi are multicellular except yeasts. Like animals, all fungi get their energy from eating. Fungi secrete digestive enzymes onto whatever they are growing. Most are decomposers that live on dead organisms, but some are parasites.

Plantae Kingdom Plantae includes all the plants. All are multicellular. All are autotrophs, which means they convert the sunlight into energy. They are non-motile, which means they can’t move from place to place. Many of their adaptations, such as seeds, are a way to overcome this disadvantage.

Animalia Animals are multicellular eukaryotes. All animals get their energy from other organisms. Animals are either vertebrates, which means they have a backbone, or invertebrates, which means they don’t have a backbone. Of the 1 million species of animals, only about 42,500 are vertebrates!