1 / 32

Chapter 3

Chapter 3. The Diversity of Life Part Two: Classification and Diversity. Taxonomic Groups. Six kingdoms Prokaryotes 1. Archaeobacteria 2. Eubacteria Eukaryotes 3. Plantae producer 4. Fungi consumer 5. Animalia consumer 6. Protista. http://www.ucmp.berkeley.edu/.

phallon
Télécharger la présentation

Chapter 3

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. Chapter 3 The Diversity of Life Part Two: Classification and Diversity

  2. Taxonomic Groups • Six kingdoms • Prokaryotes 1. Archaeobacteria 2. Eubacteria • Eukaryotes 3. Plantae • producer 4. Fungi • consumer 5. Animalia • consumer 6. Protista http://www.ucmp.berkeley.edu/ http://tolweb.org/tree/phylogeny.html

  3. Systematics Understanding the history of life Systematics is based on our understanding the life diversified from a single origin. Diversity is a product of descent with modification. • Taxonomy • Naming and classification of life • System of organizing the relationships between organisms • Taxonomic groups • The six kingdoms and their subordinate groups

  4. Taxonomic Groups • Taxa range from broad (phylum) to narrow (species) Kingdom Animalia Phylum Chordata Class Mammalia Order Primates Family Hominidae Genus Homo Species Homo sapiens • Species • Group of individuals that can interbreed • Name includes genus • Italicized

  5. Taxonomic Groups • Primitive traits • Appear early in evolutionary history • Hagfish group traits • Derived traits • Evolved later • Present only in some subgroups • Jaws, lungs, claws or nails, feather, fur, and mammary glands

  6. Prokaryotes- Eubacteria Prokaryotes: Unicellular (mostly) organisms without a nucleus Bacteria may be aerobic or anaerobic Classified as 1. heterotrophs fermentation and respiration 2. autotrophs photoautotrophic or chemoautotrophs • Critical to Earth System as a mechanism for recycling nutrients like carbon, nitrogen and sulfur • Carbon is removed from the atmosphere by plants. Bacteria oxidize this carbon after plants death, which recycles it back to the atmosphere as CO2. No CO2= No plants= No life • Oldest known fossils are 3.5 billion years old: bacteria like organisms • Most common in rock record are stromatolites: Layered mats of cyanobacteria Photo: http://www.sharkbay.org/terrestial_enviroment/page_15.htm

  7. Prokaryotes- Archaeans • Discovered in the 1970’s • Inhabit extreme environments • Temperatures >100 degrees Centigrade • Hot springs • Low or no oxygen • Alkaline or Acidic conditions • They are methanogens: they produce methane • Have probably not changed much through time: recognized as far back as 3.8 bya http://www.ucmp.berkeley.edu/archaea/archaeasy.html - No driving mechanism for evolution. No competition.

  8. Eukaryotes: Protista • Eukaryotes: organisms with complex cells with nuclei. • Protozoans (single celled, nuclei) • Animal-like protists divided on the basis of locomotion and morphology • Amoebas • Change shape • Flagelleates • Flagellum for locomotion • Ciliate • Cilia for locomotion

  9. Protista • Unicellular algae • Plant-like protists • Dinoflagellates • Diatoms: chert • Calcareous nannoplankton: chalk • Originated in the Mesozoic Era • Important marine producers

  10. Protista Protozoans with skeletons • Foraminifera Chambered skeleton of calcium carbonate Very abundant Useful for dating rocks and sediments Why? They are good index fossils. Planktonic, over 250,000 species, distinct ranges

  11. Protista • Protozoa with skeletons • Radiolarians • Skeleton made out of opal (SiO2): chert • Related to foraminifera

  12. Eukaryotes: Fungi • Decomposers • Obtain nutrients from dead organisms using digestive enzymes (heterotrophs) • Spore producers • Diverse • Yeast • Mushroom • Poor fossil record

  13. Plants • First land plants in the Ordovician (490-443my) • Vascular versus Non-vascular • Vessels for transport of water, dissolved nutrients, food • Transportation of materials by diffusion • Example: Mosses

  14. Spore Plants • Ferns • Devonian (417-354my) • Adapted to life on land with roots and leaves • Spores • One set of chromosomes • Fertilized by sperm • Sperm migration requires moisture • Vast Late Paleozoic swamps led to coal formation • Origin of name “Pennsylvanian Period” after coal mines in Pennsylvania

  15. Seed Plants • Seeds enabled plants to exploit drier, non coastal habitats • Gymnosperms • Greek word meaning “Naked seed” plants • Conifers • Cone-bearing plants • Eggs are fertilized in cone by pollen • Pollen bears sperm; carried by wind • Dominant in the Mesozoic • Angiosperms • Flowering plants • Pollen carried by pollenators (animals) • Dominant in the Cenozoic http://en.wikipedia.org/wiki/Angiosperm http://www.ucmp.berkeley.edu/seedplants/seedplants.html

  16. Animalia • Two groups • Vertebrates • Possess a backbone • Invertebrates • Coelomates • Body cavity housing internal organs

  17. Animals- Sponges • Simple invertebrates • Suspension feeds • Strain particles from water • Mostly eat bacteria • Flagella pump water through internal canals • Calcium carbonate or silica spicules support structure • Cambrian - modern

  18. Cnidarians • Jellyfish and corals • Polyp and Medusae stage • Radial symmetry and more complex body plan including mouth, tentacles and digestive cavity

  19. Arthropods • Insects, crabs, spiders, lobsters, trilobites • Trilobite • Three-lobed body • Central, left-and right- lobed • External skeleton • Gill-like structure for respiration • Legs • Primitive eyes • Common in Cambrian (560-490 mya) • Illustrates that complex life formed early in Earth History and challenges traditional view of evolution as a move from primitive to advanced forms of life.

  20. Mollusks • Bivalves (Clams) • Gastropods (snails) • Cephalopods (octopuses) • Shell of aragonite, calcite, or both • All share a common body plan, though they evolved to fit different ecological niches: crawlers, filter feeders, swimmers

  21. Mollusks • Cephalopods • Squids, octopuses, chambered nautilusses • Swim in the sea • Jet propulsion • Eyes • Carnivores • Catch with tentacles • Eat with strong beak • Chambered nautilus • Bouyancy due to gas in shell • Pressure accomodated by increased surface area • Common in Phanerozoic

  22. Lophophores • Brachiopods • Shell divided into two valves • Lampshells • Lophophores • Pump water • Strain food • Inarticular brachiopods • Lack hinge teeth • Lingula • Articulate brachiopods

  23. Bryozoans • Moss animals • Ressemble corals, but more closely related to brachiopods • Lophophore extended from skeleton to feed • Calcified skeleton • Colonial • Ordovician

  24. Echinoderms • Spiny-skinned form • Five-fold symmetry • Starfishes • Predators • Lower Paleozoic • Sea urchins • Regular sea urchins • Radially symmetrical bodies • Irregular sea urchins • Bilaterally symmetric • Burrowers

  25. Echinoderms • Crinoids • Sea lillies • Sieve food using arms • Pass food to mouth with tube feet • May swim • May be attached by flexible stalk • Disk-shaped plates from stalk

  26. Chordates Notochord, Gills and Tail Notochord • Flexible, rodlike structure that supports body for some part of life cycle • Spinal cord • Runs next to notochord

  27. Vertebrates

  28. Vertebrates • Fishes • Devonian 417 to 354 mya: Age of Fishes • Jawless Fishes “Class Agnatha” • Placoderms: Earliest jawed fishes. Armored plates but no teeth- sharp jaws instead. Devonian • Ray-finned fishes • Fins supported by thin bones radiating from body • Lobe-finned fishes (sharks) • Tetrapods: Amphibians • Amphi meaning both, Bios meaning life • 3000 living species • Devonian: Ichthyostega climbs to shore in Greenland An Ichthyosaur

  29. Vertebrates: Tetrapods • Tetrapods: Reptiles • Eggs with protective shells • Ectothermic • Environment controls internal body temperature • Question: What might be an advantage of this quality? • Dinosaurs • Primitive reptiles 225 to 65 mya • Birds • Endothermic • Evolved from Dinosaurs

  30. Vertebrates: Tetrapods • Mammals • Endothermic; Hair • Bear live young • Monotremes • Mammals that lay eggs • Marsupial • Offspring develop in pouch • Placental

  31. How often do geologists find new species? What kind of fossils are in N. Idaho? What is the most common type of fossil found today? Total named species on Earth: 1.5 million. Actual number may= 100 million (mostly insects), but probably around 13-14 million. (Society for Conservation Biology) Grad student here in department found new species of brachiopod, got to name it. Stephen J. Gould estimated that 99% of all plant and animal species are exinct. Hagerman Fossils (S. Idaho): Pliocene age (3.7-3.1my). 140 species including horses, saber tooth cats, ground sloths… Miocene (20my) Plant Fossils Cambrian Trilobites at Lake Pend Oreille (545-495my) Answers to your questions… Fungal Spores from the Rhynie Chert, Scotland Devonian age (417-354my)

More Related