Lesson 13: Species Diversity and Cladistics

1. Lesson 13: Species Diversity and Cladistics

2. Talkie Time: Animal ResearchRecap of last lesson

3. Learning Competency: Describe species diversity and cladistics, including thetypes of evidence and procedures that can be used toestablish evolutionary relationships - STEM_BIO11/12IIIh-j-16

4. Activity: Watch a Video on Cladistics • https://www.youtube.com/watch?v=NRVJyUZoQow • Answer the following questions: • What is Taxonomy? What is cladistics? • What are the different bases of classifying organisms? • What are the different kingdoms of classification and their characteristics?

5. Cladistics • Derived characteristic: similarity that is inherited from the most recent common ancestor of an entire group • Ancestral: similarity that arose prior to the common ancestor of the group • In cladistics, only shared derived characters are considered informative about evolutionary relationships • To use the cladistic method character variation must be identified as ancestral or derived

6. Cladistics • Characters can be any aspect of the phenotype • Morphology - Physiology • Behavior - DNA • Characters should exist in recognizable character states • Example: Teeth in amniote vertebrates has two states, present in most mammals and reptiles and absence in birds and turtles

7. Cladistics Examples of ancestral versus derived characters • Presence of hair is a shared derived feature of mammals • Presence of lungs in mammals is an ancestral feature; also present in amphibians and reptiles

8. Cladistics Construction of a cladogram • Polarize characteristics • Clade: species that share a common ancestor as indicated by the possession of shared derived characters • Clades are evolutionary units and refer to a common ancestor and all descendants • Synapomorphy: a derived character shared by clade members

9. Cladistics • A simple cladogram is a nested set of clades • Plesiomorphies: ancestral states • Symplesiomorphies: shared ancestral states, not informative about phylogenetics.

11. Cladistics • Homoplasy: a shared character state that has not been inherited from a common ancestor • Results from convergent evolution • Results from evolutionary reversal • If there are conflicts among characters, use the principle of parsimony which favors the hypothesis that requires the fewest assumptions

12. Cladistics Parsimony and Homoplasy

13. Cladistics A Cladogram; DNA

14. The grouping of organisms into KINGDOMS is based on 3 factors: • 1. Cell Type (prokyotic or eukaryotic) • 2. Cell Number (unicellular or multicellular) • 3. Feeding Type (autotroph or heterotroph)

15. 1. Cell Type- The presence or absence of cellular structures such as the nucleus, mitochondria, or a cell wall Prokaryotes or Eukaryotes

16. Prokaryotes – Bacteria! • DO NOT HAVE: • An organized nucleus • Structured organelles

17. Prokaryotes – Typical Bacteria • DNA – strands floating in cytoplasm/small rings called plasmids Basic Structure • Ribosomes- RNA/protein synthesis sites • Cytoplasm-water based • Cell membrane & Wall

19. Eukaryotes • Nucleus organized with a membrane • DO HAVE: • other organelles

21. Unicellular- single celled organism – protozoans, bacteria, some algae 2nd criteria for Kingdom Divisions: Cell Number • Multicellular- many celled organism – cells start to specialize/differentiate

22. Multicellular • Unicellular

23. Autotroph or Producer Make their own food 3rd Criteria for Kingdom Divisions Feeding Type - How the organisms get their food • Heterotroph or Consumer Must eat other organisms to survive Includes decomposers – those that eat dead matter!

24. This kingdom has now been divided into 2 – archaebacteria & eubacteria There used to be only 5 kingdoms • Moneran • Protista • Fungi • Plantae • Animalia

25. 6 Kingdoms Prokaryotes • Archaebacteria • Eubacteria • Protista • Fungi • Plantae • Animalia Eukaryotes

27. Archaebacteria • Ancient bacteria- • Live in very harsh environments • extremophiles

28. Eubacteria • It is the eubacteria that most people are talking about when they say bacteria, because they live in more neutral conditions.

29. Bacteria • Bacteria are unicellular prokaryotes

30. Bacterial Shapes • Bacteria come in 3 main shapes • Rod or Stick (bacilli) • Sphere (cocci) • Helical or spiral (borrelia)

31. Bacterial Locomotion • Some bacteria have flagella or cilia for movement • Some secrete a slime layer and ooze over surfaces like slugs

32. Bacterial Nutrition • Some bacteria are autotrophs and can photosynthesize • Some bacteria are heterotrophs

33. Protists • Protists include many widely ranging microbes, including slime molds, protozoa and primitive algae. Odds & Ends Kingdom

34. Protista Kingdom • There are animal-like, fungus-like, and plant-like protists • Some are beneficial • Some protists can cause diseases in humans, such as:

36. Protists Disease Ameba histolytica • Amebic dysentery

37. Protists Disease • Giardiasis (beaver fever) Giardia

38. Protists Disease Trypanosoma • African Sleeping Sickness

39. Protists Disease • Malaria Plasmodium

40. Protists Disease • Toxoplasmosis Toxoplasma

41. Protists Locomotion • 3 types of movement: • Pseudopod (false foot) • Flagella/cilia • Contractile vacuoles

42. Protists Nutrition • Protists can be autotrophs or heterotrophs

43. Fungi Kingdom • The Kingdom Fungi includes some of the most important organisms. • By breaking down dead organic material, they continue the cycle of nutrients through ecosystems.

44. Fungi Unicellular (yeast) Multicellular • All fungi are eukaryotic • They may be unicellular or multicellular • All fungi have a cell wall

45. Fungi Penicillin • Fungi can be very helpful and delicious • Many antibacterial drugs are derived from fungi

46. Fungi • Fungi also causes a number of plant and animal diseases: • Athlete's Foot

47. Fungi • Ringworm

48. Fungi Locomotion • Fungi are stationary • They have root-like structures that they use for attachment

49. Fungi Nutrition • All fungi are heterotrophs - Saprophytes-get their nutrients from dead organic matter - Mutualists – live symbiotically - Parasites – absorb from a host, eventually killing the host

50. There are 4 main types of Fungi (classified by how they reproduce) • Zygospore (Zygosporangia) common bread molds reproduce by “spores”- asexual reproduction!