1 / 41

Classification of Living Things

Classification of Living Things. Classification of Living Things. Taxonomy : science of classification Branch of biology that names organisms according to their characteristics, and places them into orderly groups based on similar characteristics. Why ?

dalton
Télécharger la présentation

Classification of Living Things

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 of Living Things

  2. Classification of Living Things • Taxonomy: science of classification • Branch of biology that names organisms according to their characteristics, and places theminto orderly groups based on similar characteristics. • Why ? • Biologists classify living organisms to answer questions such as: • How many known species are there? • What are the defining characteristics of each species? • What are the relationships between these species?

  3. Aristotle (350 B.C.) • Aristotle • Greek philosopher and teacher more than 2000 years ago • The first person to devise a classification system-according to natural environment

  4. Aristotle ANIMALS: PLANTS: Based on size of stem Based on where they lived

  5. John Ray • 17th Century • Classified according to characteristics • Why are there problems with this???

  6. Limitations of Early Classification 1. Not all organisms fit into Aristotle’s 2 groups (plants or animals) Ex: Bacteria Fungi Images from: http://www.leighday.co.uk/upload/public/docImages/6/Listeria%20bacteria.jpg http://danny.oz.au/travel/iceland/p/3571-fungi.jpg

  7. Limitations of Early Classification Ex: A jelly fish isn’t a fish, but a seahorse is! 2. Common names can be misleading Sea cucumber sounds like a plant but… it’s an animal! Image from: http://www.alaska.net/~scubaguy/images/seacucumber.jpg

  8. Limitations of Early Classification 3. Common names vary from place to place Ex: puma, catamount, mountain lion, cougar are all names for same animal Image from: http://www4.d25.k12.id.us/ihil/images/Cougar.jpg

  9. Limitations of Early Classification 4. Same organisms have different names in different countries. Chipmunk Streifenhornchen (German) Tamia (Italian) Ardilla listada (Spanish) Image from: http://www.entm.purdue.edu/wildlife/chipmunk_pictures.htm

  10. Limitations of Early Classification • Early Solution: • Description of Organism Using Latin Names RED OAK Quercus foliis obtuse-sinuatis setaceo-mucronatis “oak with leaves with deep blunt lobes bearing hairlike bristles”

  11. Limitations of Early Classification • Problem with Latin Name descriptions? • Names too long and difficult to remember • Names don’t illustrate evolutionary relationships

  12. Carolus Linneaus • Devised a new classification system based on morphology (Organism’s form and structure) • Formed a species • Similar species group together to form a genus (1707-1778) “Father” of taxonomy and binomial nomenclature

  13. Use of genus and species names to form scientific name • This system is called binomial nomenclature • Binomial means two parts • Nomenclature means system of naming • Latin is used-dead language

  14. Binomial Nomenclature • Binomial Nomenclature: Two name naming system • Italicized or Underlined • 1st Name = Genus • Capitalized • 2nd Name = Species Identifier • Lower case

  15. Binomial Nomenclature Vampire batDesmodus rotundus Image from: http://212.84.179.117/i/Vampire%20Bat.jpg Eastern chipmunk Tamiasstriatus Image from: http://www.entm.purdue.edu/wildlife/chipmunk_pictures.htm

  16. Binomial Nomenclature Humans Homo sapiens Homosapiens Image from: http://www.earlylearning.ubc.ca/images/photo_baby.jpg

  17. Robert Whittaker-1969 • 5 kingdom system of naming • Animalia, Plantae, Protista, Monera, Fungi • Levels of classification from broadest to narrowest • KPCOFGS

  18. Kingdom • Phylum • Class • Order • Family • Genus • Species Kings Play Cards On Fat Green Stools

  19. Kingdom • Phylum • Class • Order • Family • Genus Species Animalia Chordata Mammalia Carnivora Felidae Panthera leo http://www.vetmed.wisc.edu/dms/fapm/personnel/tom_b/2004-lion.jpg

  20. Modern Taxonomy Modern taxonomy involves early naming/classification system, but with additional kingdom. Domain is the most general grouping

  21. Modern Taxonomy • Organizes living things in the context of evolution

  22. Modern Taxonomy • Scientists use a variety of information in order to classify organisms: • Chromosome Structure • Reproductive Potential • Biochemical Makeup/Protein Comparison • Morphology- Homologous Structures

  23. 1. Chromosomes Similar karyotypes suggest closer relationships. Indicates similar DNA/RNA structure by comparing base sequences Human: http://www.nationmaster.com/wikimir/images/upload.wikimedia.org/wikipedia/en/thumb/1/18/300px-Human_karyogram.png Chimpanzee: Middle School Life Science , published by Kendall/Hunt.

  24. Human- 46 chromosomes Chimpanzee- 48 chromosomes Even differences show relatedness Chimpanzees have 2 smaller chromosome pairs we don’t have Humans have 1 larger chromosome pair (#2) they don’t have. Human: http://www.nationmaster.com/wikimir/images/upload.wikimedia.org/wikipedia/en/thumb/1/18/300px-Human_karyogram.png Chimpanzee: Middle School Life Science , published by Kendall/Hunt.

  25. 2. Reproductive potential • If two organisms can interbreed AND produce fertile offspring they are considered of the same species

  26. 3. Biochemical makeup Comparison of macromolecules such as Proteins Similar amino acid sequences in proteins indicate similar organisms

  27. Macromolecules

  28. 4. MORPHOLOGY Shape and Function Image from: http://www.angelfire.com/ab7/evolution12/evolutionclues.html

  29. Morphology • Homologous Structures: • Embryological source of similar structures indicate a possible common ancestor • Example: Bat Wing and Human Arm • P. 262

  30. Morphology Bat wing and human arm develop from same embryonic structures HOMOLOGOUS STRUCTURES

  31. Morphology • Analogous Characteristics: • May have similar function, but different embryological origin • Example: Bird Wing and Butterfly Wing Analogous characteristics evolved separately. Organisms not necessarily closely related.

  32. ANALOGOUSSTRUCTURES Bird wing and butterfly wing have evolved with similar function BUT different structure inside. http://uk.dk.com/static/cs/uk/11/clipart/bird/image_bird003.html Insects and birds NOT closely related! http://www.naturenorth.com/butterfly/images/05a%20tiger%20wing.jpg

  33. I don’t get it?!Think in terms of structure. • Analogous characters the same function but different underlying structure. • Homologous characters different functions, but similar structure inherited from a common ancestor. **Important for cladograms!**

  34. Cladistics Phylogeny: Evolutionary History Reflect an organism’s evolutionary history Shows evolutionary relationships based on “shared derived characteristics” Cladistic relationships illustrated through the use of a Cladogram

  35. Cladogram • The greater the number of derived characters shared by groups, the more recently the groups share a common ancestor.

  36. Dichotomous Key A dichotomous key is used to classify an organism by physical characteristics. Made of couplets of opposing meaning.

  37. Domain Bacteria Archaea Eukarya

More Related