Chapter 18 Classification

Systematics = science of naming and grouping organisms Aristotle – B.C. – 1st to group living things - 2 kingdoms – Plant or Animal

Carolus Linnaeus – 1730s – Swedish botanist Binomial nomenclature – 2 part scientific name Scientific name = Genus species or Genus species Ex. Homo sapien or H. sapien

Ex. Carnegiea gigantia giant Segauro cactus Ex. Permyscus californicus common California mouse Ex. Nymphea odorata fragrant water lily Name – location, characteristics, scientist

Grouped organisms by morphology (form & structure) Also – 2 kingdoms

Developed hierarchy : - Kingdom – broadest - Phylum - Class - Order - Family - Genus - Species – most specific

Modern – use evolutionary relationships as well Cladogram – diagram that links organisms by showing how evolutionary lines branched off from common ancestors Based on a derived character = trait that arose in the most recent common ancestor and was passed on

Cladogram Clade Tetrapoda Clade Amniota Clade Mammalia Clade Carnivora Clade Felidae Four limbs A derived character, like retractable claws, is a trait shared by all members of a clade and only by members of that clade.

Dichotomous Key Used to identify organisms Uses if … then statements

Six Kingdoms Animalia Plantae Fungi Protista Archaebacteria Eubacteria

Three Domains Domain – based on rRNA sequences 3 Domains - Archae (K. Archaebacteria) - Bacteria (K. Eubacteria) - Eukarya (K. A, P, F, P)