Topic 5: Evolution by Natural Selection - part 1 & 2

• what book did charles darwin publish

  On the Origin of Species by Means of Natural Selection
• what two points did charles darwin make in his book

  1. species show evidence of "descent with modification" from common ancestors (evolution)

  2. Natural selection is the mechanism for "descent with modification"
• what are the main principles of natural selection


  • there is variation within a population of organisms and this variation can be inherited
  • individuals with inherited traits that are better suited for growth and reproduction in a given environment contribute disproportionately to the next generation
• What is natural selection?

  the process in which individuals with favourable inherited traits are more likely to survive and reproduce
• prior to darwins work, how was earth viewed

  viewed as being geologically young and inhabited by unchanging species
• what helped to lay the groundwork for darwins ideas

  fossils
• what are fossils


  fossils are remains or traces of organisms from the past
• where are fossils usually found

  sedimentary rock, which appears in layers of strata
• how did they know that extinction occured


  fossils did not look like living organisms
• what did georges curvier note

  he noted that fossils from older strata were dissimilar to living organisms and that fossil species changed between strata (extinction)
• what did georges curvier propose


  that the fossil record represented catastrophism
• what does it mean when Cuvier proposed that the fossil record represented catastrophism

  it means each boundary between strata represents a catastrophic event
• what did Cuvier believe that went against Darwin

  he believed that species did not change overtime

  i.e. no evolution
• what was Cuviers explanation for new fossils


  a catastrophy would happen then new species moved into the area
• What did Jean-Baptiste Lamarck hypothesize

  that the apparent disappearance of species was actually one species changing slowly into another
• how did Lamarck think that one species morphed into another?

  through use and disuse of body parts and inheritance acquired characteristic
• what are inheritance of acquired characteristics


  use and disuse of a structure which is heritable change
• Why was Lamarck wrong?

  He believed in the inheritance of acquired characteristics-just because you bleach your hair doesnt mean your child will be blonde
• what did darwin first study

  medicine
• what did darwin study after he studied medicine

  theology which is biology and geology
• what led to darwins fundamental work and his book

  the observations he made during his voyage
• what was the main purpose of darwins voyage

  to map the coast line of south america
• what did darwin note when he collected specimens from south america

  he noted that species' traits match the environment they inhabit
• what did darwin observe about fossils

  fossils resembled living species from the same region
• why was the earthquake important to darwin

  he discovered fossils
• what book strongly influenced darwin

  principles of geology by charles lyell's
• what did the book Principles of Geology by Charles Lyell describe

  described gradualistic process in geology
• what was charles darwins interest in geopraphic distribution kindled by

  a stop at the galapagos islands
• what was charles darwins hypothesis about the galapagos islands

  that species from south america colonized the galapagos and speciated on the islands
• what is natural selection

  the a process in which individuals with favourable inherited traits are more likely to survive and reproduce
• what were darwins two main points in The Origin of Species

  1. Species show evidence of "descent with modification" from common ancestors (evolution).2. Natural selection is the mechanism for "descent with modification"
• what did charles darwins theory of natural descent agree with?

  Linnaeus' hierarchical classification
• darwin said that large morphological gaps between related groups could be explained by what

  by branching processes and past extinction events
• What word did Darwin never use in his first edition of The Origin of Species?


  evolution
• "decent with modification" explains what


  the duality of unity and diversity in living organisms
• similar traits among organisms are due to what

  unity
• differences among organisms are due to what

  diversity
• What does adaptation mean?

  inherited characteristics of an organism that enhances its survival and reproduction in a specific enviornment
• recent research on the galapagos finches demonstrates what

  the connection between adaptation and speciation
• how are galapagos finches united

  the basic body structure