Biological Classification Group the following in any way you would like, but justify your grouping! • • • • • Frogs Bears Ants Spiders Bacteria • • • • • Humans Dolphins Sharks Mushrooms Pine Trees Why do we Classify? • To group organisms according to similarities • Taxonomy is the science of classifying organisms. Binomial Nomenclature • Binomial Nomenclature - the formal system of naming species. (Bi = two, nomial = names) – Latin is the language in which scientific names are written. • Carolus Linnaeus (1707 – 1778) a Swedish botanist , came up with the b.n. system. • Aristotle was the first scientist to group organisms based on physical characteristics. The 3 Domains Archaea The Five The Three Domains Kingdoms Eubacteria Eukaryota The 5 Kingdoms Monera Fungi Protista The Five Kingdoms Animalia Plantae 7 Levels of Classification 1 is Largest- 7 is Smallest 1. Kingdom 2.Phylum 7. Species 7 Levels of Classification 6. Genus 5. Family 3. Class 4. Order Examples of Classification • • • • • • • Common Pond Amoeba KINGDOM: Protista PHYLUM: Sarcomastigophora CLASS: Sarcodina ORDER: Granulopodea FAMILY: Amoebidae GENUS: Amoeba SPECIES: Amoeba proteus Examples of Classification • • • • • • • Humans KINGDOM: Animalia PHYLUM: Chordata CLASS: Mammalia ORDER: Primata FAMILY: Hominidae GENUS: Homo SPECIES: Homo sapiens Scientific Names • The GENUS is the 1st word in the scientific name. Always capitalized Example : Amoeba proteus Homo sapiens • The SPECIES is the 2nd word in the scientific name. Always lowercase Example: Amoeba proteus Homo sapiens Phylogenetic Tree • A Phylogenetic Tree is a way to organize living things and show how they are related. Cladograms • Cladograms are a way to show shared or lost traits between related organisms How do we know how to classify? • Similar Structures • Similarities in genes (DNA – The bones in a bat’s wing are sequence or almost the same as proteins) the bones in a human hand • Similar Behaviors – All mammals nurse their young – Human and Primate DNA is 99% similar Evidence for Classification/Evolution • Homologous structures: similar bone structures in different organisms • Fossil Record: Past organisms can be studied through fossils • Gene similarities: matching DNA sequences • Embryology: similar development patterns in unborn species of different species • Hybridization: ability to successfully interbreed different species. Homologous Structures Embryology Hybridization