Chapter 17 – Organizing Life’s Diversity I.Classification – grouping of objects or organisms based on a set of criteria; 2 scientists A. Aristotle ( B.C.): Greek philosopher who grouped organisms as either plants or animals

B.Carolus Linnaeus ( ) – Swedish naturalist who grouped organisms based on morphology, behavior, & habitat 1.Taxonomy – branch of Biology where species are identified, named, & classified based on natural relationships II.Binomial Nomenclature – a system that gives each species a scientific name that has 2 parts A.1 st part: genus name; capitalized 2 nd part:specific epithet/name; it IDs the species; lowercased

B.Writing Scientific names 1.italicized when typed: Homo sapiens 2.in handwriting: Homo sapiens C.Latin is the language of Binomial Nomenclature – why?  It is no longer used in conversation and, therefore, does not change D.Common names are confusing & vary in use 1.A starfish isn’t a fish 2.A sea horse is a fish, not a horse 3.Sea cucumbers are not plants

III.Taxonomic Categories – these are a nested, hierarchical system, where each category is contained within another from broadest to most specific A.The broader the characteristics, the more species the taxon contains

1.Species – smallest taxon; organisms that are able to interbreed & produce fertile offspring in a natural setting 2.Genus – group of species that are closely related & share a common ancestor 3.Family – group of similar, related genera (plural of genus) 4.Order – group of related families 5.Class – group of related orders 6.Phylum / Division – group of related classes 7.Kingdom – group of related phyla/divisions 8.Domain – largest taxon; group of related Kingdoms

B.Example in Humans: TaxonNameShared with? D-DearEukarya all other organisms w/ nuclei & organelles in their cells K-KingAnimaliaall other animals P-PhillipChordatawith a spinal cord C-CameMammaliahairy; young are fed milk O-OverPrimateopposable thumbs F-ForHominidaeprimates w/ social skills & complex intelligence G-GoodHomoall humans, including those that are extinct S-Spaghetti sapiensus – the only humans alive

C.Dichotomous Key – a key made up of sets of numbered yes/no statements 1.Has green colored body......go to 2 Has purple colored body..... go to 4 2.Has 4 legs.....go to 3 Has 8 legs Deerus octagis 3.Has a tail Deerus pestis Does not have a tail..... Deerus magnus 4.Has a pointy hump Deerus humpis Does not have a pointy hump.....go to 5 5.Has ears Deerus purplinis Does not have ears......Deerus deafus

IV.Phylogeny – the evolutionary history of a species, based on characters (inherited, varied features) A.Morphological – similar parts suggest a relationship beaks of Galapagos finches bones in vertebrate limbs

B.Biochemical – similar amino acids & nucleotides in DNA suggest a relationship 1.Cauliflower & Broccoli look different, but have almost identical DNA (mustard)

C.Cladogram – a branching diagram that represents the proposed phylogeny or evolutionary history of a species or group

D.The 3 Domains w/ 6 Kingdoms – differ in cell type & structure (pg. 502)

DomainKingdomCharacteristics  Bacteria  (Eu)Bacteria cell walls w/ peptidoglycan, unicellular  Archaea  Archaea(bacteria)cell walls w/o PG, unicellular  Eukarya  Protistacell walls w/ cellulose in some, unicellular or multicellular  Fungicell walls w/ chitin, mostly multicellular, heterotrophs  Plantaecell walls w/ cellulose, multicellular, autotrophs  Animaliano cell walls, multicellular, heterotrophs Eukaryotes Prokaryotes Autotrophs OR Heterotrophs

Evolution of the 6 Kingdoms of Life Common Ancestor Older, Less Complex Newer, More Complex Archaea Bacteria Protista Animalia FungiPlantae

The 6 Kingdoms of Life