1 / 21

Classification

Biologists classify organisms to study their diversity and establish meaningful groups. The history of scientific naming, binomial nomenclature, and Linnaeus’s taxonomy system are explained. The classification of Grizzly bears as an example, shows how genera and families are organized based on shared characteristics. The shift towards modern evolutionary classification, emphasizing evolutionary history over physical similarities, is outlined, highlighting Darwin's impact on the field.

ethelenea
Download Presentation

Classification

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Classification

  2. Why Classify? • To study the great diversity of organisms, biologists must give each organism a name. • Biologists must also attempt to organize living things into groups that have biological meaning.

  3. Assigning Scientific Names • History • 18th century scientists recognized problem with naming organisms by their common names • cougar, puma, panther, mountain lion • UK: buzzard hawk, US: buzzard vulture

  4. Why all the weird names? • 18th century scientists understood Latin and Greek

  5. Early efforts at naming organisms • 1st attempts at naming organisms often described physical characteristics • PROBLEMS • some names were 20 words long • Different scientists described different characteristics

  6. Binomial Nomenclature • (Carolus Linnaeus ~ Swedish botanist) • Two word naming system • 1st word is capitalized, 2nd is lowercased and italicized • 1st part GENUS / 2nd part special character or location

  7. Linnaeus’s System of Classification • Taxonomy taxonomic levels or taxon (taxa: plural) • Seven levels: • Kingdom • Phylum • Class • Order • Family • Genus • Species

  8. Kingdom ~ King • Phylum ~ Phillip • Class ~ Came • Order ~ Over • Family ~ For • Genus ~ Great • Species ~ Soup

  9. Grizzly bear (Ursus arctos) • Genus: Ursus  group of closely related species • Contains 5 other kinds of bear including Ursus maritimus. • 2nd part: arctos / maritimus  is unique to species within genus (important trait or indication of where the organism lives ~ maritimus: sea) • Giant Panda differs enough to be placed in its own genus • Ailuropoda

  10. Grizzly bear (Ursus arctos) • Genera that share many characteristics, such as Ursus & Ailuropoda, are grouped into families ~ (Ursidae) • These bears together with 6 other families of meat-eating animals, (dogs: canidae and cats: felidae are in order Carnivora. • Carnivora is grouped into class mammalian (worm-blooded, body hair, milk) which also includes order primates (humans, apes, monkeys, prosimians) • Class mammalian is grouped with birds (aves), reptiles, amphibians, and all fish into a phylum: Chordata.

  11. Taxonomy

  12. Linnaeus only named two kingdoms (plants & animals)

  13. Modern Evolutionary Classification • Problems with traditional classification • Dolphins fish or mammals • Barnacle, limpet, crab • Because of convergent evolution, sometimes organisms that are very different evolve similar body structures

  14. Evolutionary Classification • Darwin’s theory of evolution changed the entire way that biologist thought about classification • scientists began to understand that organisms share certain traits because of their evolutionary history • Biologists group organisms into categories that represent lines of evolutionary descent, not just physical similarities.

More Related