Diversity

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Biological Diversity - Lecture 1

  • our perception = anthropocentric
  • microorganisms = key - life
  • earth formed (+ rest of solar system) - 4.5 billion years ago = 4.5×10(9)
  • age earth - uranium-lead dating
  • most common fossils - replacement, organic material after burial - minerals dissolved - water - ground + recrystallisation
  • burial - tar = fantastic detail 
  • amber (fossilised tree resin) - soft tissues preserved
  • fossil record - increasing complexity
  • key moments - evolution:
    • origin of life
    • oxygenation atmosphere
    • origin - eukaryotic cells
    • origin - multicellular organisms
    • Cambrian explosion 
    • colonisation - land, complex organisms
  • Stanley Miller's experiment = electricity - provide energy - mixture gases, closed system - amino acids formed
  • problem = atmosphere - different - gases used
  • simple organic compounds - amino acids+nucleotides - throughout solar systems - comets+meteorites
  • long popular theory - primordial soup, sea collected - amino acids+nucleotides, joined - macromolecules (protein+DNA). problem = not concentrated enough 
  • hypothesis now widely accepted = hydrothermal vents = more concentrated solution - organic molecules. energy - heat. Black smokers - ecosystems independent - sun
  • earliest cells - bags, enabled higher concentrations nutrients build up
  • first…

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