General Biology

• Evolution


  is NOT a historical process.
• Jean-Baptiste Lamarck (1744-1829)


  - Developed one of the first theories on how species changed.

  - Concluded that organisms of high complexities evolved from pre-existing, less complex organisms.
• Three Lamarck theories:

  • Theory of Need
  • Theory of Use and Disuse
  • Theory of Acquired Characteristics
• Theory of Need


  - Organisms change because they need to.

  - For an organism to evolve a structure, it must need the structure.
• Theory of Use and Disuse


  Organisms develop specialized characteristics by the use and disuse of organs.
• Theory of Acquired Characteristics/Traits


  If a parent acquires a body structure during its lifetime, it could pass on that characteristics to its offspring.
• Disproving Lamarck

  1. Petals on flower
  2. Corsets
  3. Frequent Exercise
  4. Tails of Mice
• Who is the father of evolution?

  Charles Darwin
• Charles Darwin


  - Proposed the idea that all new species descend from an ancestor.

  - He performed an exhaustive amount of research to provide as much evidence as possible.

  - His theory of evolution by natural selection became the foundation of modern evolutionary studies.
• HMS Beagle Voyage (1831-1836)


  his voyage to the galapagos islands
• Darwin's Finches


  - Charles Darwin was able to see 13 varieties of finches, which varied in size &shape, from island to island.

  - It took him 20 years to organize the data.
• The Origin of species (1859)


  Here, Darwin presented his theory of evolution based on natural selection.
• Alfred Russel Wallace (1813-1923)


  Most famously, he had the revolutionary idea of evolution by natural selection entirely independently of Charles Darwin.
• Natural Selection


  Individuals within a population with the most favorable traits for an environment, survive and pass on those traits.
• Species Overproduction


  Organisms tend to over reproduce.
• Competition


  There is a struggle of existence & Survival of the fittest.
• Variation


  No two individuals are the same.
• Adaptation


  It is the Process of becoming better suited to the environment.
• Natural Selection


  Environment selects organisms that survived to be the parents of succeeding generations.
• Speciation


  Favorable adaptations gradually accumulate in the species and the unfavorable ones disappear.
• Sources of Evidence for evolution:

  Fossil record, Embryological development, comparative anatomy, molecular biology.
• Analogous Structure


  They serve the same function but have different embryonic origin.
• Homologous Structure


  Their limbs have different function but their embryonic origins are alike.
• Vestigal Structure


  Gradual changes have occurred through time that has, in some cases, reduces or removed the function of somebody's organs and structure.