PowerPoint Presentation - NMSU Biology

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					Admittedly, we all try hard to avoid error;
and we ought to be sad if we have made a
mistake. Yet to avoid error is a poor ideal: if
we do not dare to tackle problems which are
so difficult that error is almost unavoidable,
then there will be no growth of knowledge.
In fact, it is from our boldest theories,
including those which are erroneous, that we
learn most. Nobody is exempt from making
mistakes; the great thing is to learn from
them.

-- Karl Popper, Objective Knowledge
     http://www.treknature.com/gallery/photo160544.htm


                                                         Three Domains of Life

Kingdom
Phylum
Order
Family
Genus
Species
                  SYSTEMATIC BIOLOGY


Systematics includes:


  •Phylogenetics – study of evolutionary relationships among
  species and higher-level taxa


  •Taxonomy – naming and describing species, and classifying
  them in a manner consistent with the inferred phylogenetic
  relationships
                        BASIC PHYLOGENETICS




Monophyletic – a most recent common ancestor and all of its
descendants
   • there are two monophyletic groups in this tree B+R and C+B+R.
   • groups R and B share a more recent common ancestor than either does with group C
Phylum
   Order
         Family
            Genus

                    Species




                       Taxonomy
                       WHAT’S THE BIG DEAL?




                          Theodosius Dobzhansky
“Nothing in biology makes sense except in light of evolution.”
- Without a clear understanding of relationship and phylogeny why study a model
                                   species?
      Phylogenetic classifications are predictive



• Because relationships are reflected in the classification we
  can infer more about individuals, species, genera, etc.
Model species WHO CARES?
Arabidopsis thaliana – model species

• Small genome
• Fast reproductive cycle
• … easy to manipulate and study




Drosophila melanogaster ????
                                 Relevance of Systematics
• Ecology - need to know what species compose the relevant biological communities
• Agriculture/Plant breeding – cross domesticated varieties with wild species to introduce desired traits
• Extrapolation of research from model species – predictivity
• Drug discovery – use evolutionary relationships to guide chemists in choosing the best species to test
• Biogeography – phylogenies of species can be used to extrapolate information on the relationships of
land masses over time.
• Conservation Biology – DNA barcoding methods and the direct application of systematics is
becoming commonplace.
• Forensics – DNA identification of materials associated with crimes often employs techniques
developed by systematists



    Vinca alkaloid (vincristine) for treatment
    of childhood acute lymphoblastic leukemia
General relevance




                    Lento et al. 1998
Richard J. Schmidt Attempted Murder Trial
    Taxonomy – facilitates
 communication of information


– Think of naming individual people in modern society?
  What would life be like without an essentially binomial
  naming system?
 Taxonomy is an ancient science
• Ancient Greeks -
  Aristotle and
  Theophrastus –
• 200 BC



                         Aristotle
                 Basic Taxonomy
• Classifications

• Species descriptions

• For plants these are presented in –

   – Floras - classification and description of taxa from a geographic
      region – e.g., Flora of New Mexico, Flora of North America, etc

   – Monographs - a work that focuses on all members of a group of
      plants, not just plants from one area
Hierarchical classification: ranks
   • ranks above genus are indicated by standard endings
   • taxa at ranks above genus are also based on genus names included these
   taxa; last week, we looked at Ranunculaceae, which includes the genus
   Ranunculus.

         Phylum “-ophyta” (Lycopodiophyta)
            Class “-opsida” (Lycopodiopsida)
               Order “-ales” (Lycopodiales)
                  Family “-aceae” (Lycopodiaceae)
                    Genus -no standard ending (Lycopodium)
                     Species -no standard ending; (Lycopodium annotinum L.)
RELEVANCE OF SYSTEMATICS




    Systematics
                             Bacteria


                             Archaea

                             Animals
                             Fungi
                             Slime molds

                             Alveolates

                             Strameno.

                             Euglenoids




                             Glaucophytes



                             Rhodophytes
                                             Is Systematics Dynamic?




                              Green Plants
Modified from Baldauf 2000
The Tree of Life                  David Maddison


        http://tolweb.org/tree/phylogeny.html
         Major plant discoveries in recent years
• Origin of the Angiosperms?
• Monocots vs. Dicots?
• Nelumbo (a “water lily”) and
  Sycamore (Platanus sp.)!!?




                                                                           Platanus sp.
         http://www.missouriplants.com/Yellowalt/Nelumbo_lutea_page.html



         Nelumbo nucifera
        Major plant discoveries in recent years


• Wollemia nobilis (Wollemia pine) – Australia, just outside
  Sydney!
                 Other than plants?


•   5 kingdom system is flawed?
•   New Vertebrates – Vietnam
•   New forms of life in extreme habitats
•   Birds are living dinosaurs?
•   New Species of Monkey - Callicebus caquetensis from the
    Amazon in August 12, 2010.
                               What’s Left?




1. Bacteria (4,000); 2. Scarlet waxy cap mushrooms (Fungi-72,000); 3. Sea collander
     (Algae-40,000); 4. Trees, shrubs, and other higher plants (270,000); 5. Amoeba
     (Protozoa-40,000); 6. Yellow tube sponge (Sponges-10,000); 7. Compass jellyfish
     (Corals, jellyfish, and relatives-10,000); 8. Leopard flatworm (Flatworms-20,000); 9.
     Roundworms (25,000); 10. Earthworm (Earthworms and relatives-12,000); 11.
     Scallop (Clams, squids, and other mollusks-70,000); 12. African sea star (Starfish and
     relatives-6,100); 13. Dragonfly (Insects-950,000); 14. Jumping spider (Spiders,
     crustaceans, and other non-insect arthropods-123,400); 15. Regal angelfish (Fishes,
     tunicates, and lancelets-19,000); 16. Leopard frog (Amphibians-4,200); 17. Scarlet
     king snake (Reptiles-6,300); 18. Tree swallow (Birds-9,000); 19. Giraffe (Mammals-
     4,000).
                 RELEVANCE OF SYSTEMATICS




• Archaea
• Eubacteria
                   ORGANISM Plastid Euonymus alatus
• Eukaryota
                   Eukaryota; Viridiplantae; Streptophyta;
• Viroids          Embryophyta; Tracheophyta;
• Viruses          Spermatophyta; Magnoliophyta;
                   eudicotyledons; core eudicots; Rosidae;
• Other            eurosids I; Celastraceae; Euonymus.
• Unclassified

				
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