Linnaeus developed the scientific naming system still used today. Taxonomy is the science of naming and classifying organisms. A taxon is a group of organisms in a classification system. Monodon monoceros Ailuropoda melanoleuca

Taxonomists give a unique scientific name to each species they know about whether it’s alive today or extinct. The scientific name comes from one of two “dead” languages – Latin or ancient Greek. Why use a dead language?

Why use a dead language? There are at least 50 common names for the animal shown on the previous 4 slides. Common names vary according to region. Scientific names allows scientists to communicate about the same animal across different regions and languages.

Binomial nomenclature is a two-part scientific naming system. uses Latin words scientific names always written in italics or underlined if handwritten two parts are the genus name and species descriptor

A genus includes one or more physically similar species. Species in the same genus are thought to be closely related. Genus name is always capitalized. A species descriptor is the second part of a scientific name. always lowercase always follows genus name; never written alone Melanocetus johnsonii Tyto alba

Scientific names help scientists to communicate. Some species have very similar common names. Some species have many common names.

Linnaeus’ classification system has seven levels or taxa. Each level is included in the level above it. Levels get increasingly specific from kingdom to species.

What wrong with the Linnaean classification system? Linnaeus taxonomy doesn’t account for molecular evidence. The technology didn't exist during Linneaus’ time. Linnaean system based only on physical similarities. Physical similarities are not always the result of close relationships. Genetic similarities more accurately show evolutionary relationships.

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

Cladistics is a common method to make evolutionary trees. classification based on common ancestry species placed in order that they descended from common ancestor Armadillo Glyptodon

A cladogram is an evolutionary tree made using cladistics. A clade is a group of species that shares a common ancestor.

Derived characters are traits shared in different degrees by clade members. FOUR LIMBS WITH DIGITS Tetrapoda clade 1 Amniota clade 2 Reptilia clade 3 Diapsida clade 4 Archosauria clade 5 EMBRYO PROTECTED BY AMNIOTIC FLUID OPENING IN THE SIDE OF THE SKULL SKULL OPENINGS IN FRONT OF THE EYE & IN THE JAW FEATHERS & TOOTHLESS BEAKS. SKULL OPENINGS BEHIND THE EYE DERIVED CHARACTER CLADE NODE