Taxonomy Environmental Ed. 1

Taxonomy The science of naming and classifying organisms.

Linnaean taxonomy Named after Swedish botanist Carolus Linnaeus Classifies organisms based on their physical and structural similarities Uses Binomial Nomenclature

Binomial Nomenclature System that gives each species a two-part scientific name using Latin words. First part: genus Second part: species Ex: Puma concolor

Common name: mountain lion, cougar, puma Scientific name: Puma Concolor

Linnaeus’ Classification System Has 7 Levels Kingdom Phylum Class Order Family Genus Species

Linnaean Classification System

If two species belong to the same order, what other levels in the Linnaean system must they have in common? Kingdom Phylum Class Order Family Genus Species

If two species belong to the same order, what other levels in the Linnaean system must they have in common? Kingdom Phylum Class Order Family Genus Species ANSWER: Kingdom, Phylum, Class

What limitations may the Linnaean system have? This system focuses on physical similarities alone Before technology allowed us to study organisms at the molecular level. Does not account for similarities that evolved through convergent evolution.

EX: the Red Panda which is more closely related to raccoons than Giant Panda’s.

Cladistics Classification based on common ancestry Uses evidence from living species, the fossil record, and molecular data Phylogeny: evolutionary history for a group of species.

Cladogram An evolutionary tree that proposes how species may be related to each other through common ancestors.

Animal Diversity

Each animal Phylum has a unique body plan Animals are grouped using a variety of criteria A comparison of structure and genetics reveals the evolutionary history of animals.

Vertebrates An animal with an internal segmented backbone Most obvious animals around us Make up less than 5% of all known animal species

Invertebrates Animals without a backbone Most are not closely related to each other

Phylum Chordata Contains all vertebrates and some invertebrates Vertebrates: large, active animals that have a well- developed brain encased in a hard skull. Tunicates: urochordates, including both free- swimming and sessile animals such as sea squirts. Lancelets: cephalochordates, small eel-like animals that are commonly found in shallow tropical oceans.

Tunicates

Lancelets

Chordates share 4 common features- at some stage of development 1.Notochord: flexible skeletal support rod embedded in the animal’s back. 2.Hollow nerve chord: runs along the animal’s back 3.Pharyngeal slits: through the body wall in the pharynx. Water can enter the mouth and leave without passing through the entire digestive system. 4.Tail: contains segments of muscle tissue used for movement.

Endoskeleton An internal skeleton built of bone or cartilage

Vertebrate Classes Agnatha Chondrichthyes Osteichthyes Amphibia Reptilia Aves Mammalia

Class Agnatha Oldest class of vertebrates Jawless animals Include lampreys, a type of fish

Class Chondrichthyes Cartilaginous fish Animals include sharks, rays and chimeras

Class Osteichthyes Bony Fish Have skeletons made of bone

Class Amphibia First vertebrates adapted to live both in water and on land Include salamanders, frogs, toads, and caecilians

Class Reptilia Able to retain moisture, lets them live exclusively on land. Produce eggs Include snakes, lizards, crocodiles, alligators, and turtles

Class Aves Birds Presence of feathers

Class Mammalia Animals that have hair, mammary glands, and three middle ear bones.