Evidences of Evolution

• Evolution: changes in inherited traits over successive generations in populations of organisms. it allowed organisms to survive by adapting to its surroundings.
• Four evidences of evolution:

  • Fossil records
  • Embryonic development
  • Comparative Anatomy
  • genetic information
• Fossil records: traces of organisms that lives in the past that were preserved. Documents the existence of now extinct past species that are related to present day species.
• Two types of Fossil records:

  Imprints

  Compressions
• Two methods of figuring the age of fossils:

  Relative dating

  Radiometric Dating
• Relative dating: comparing the age of rock to the age of its surrounding rock layers.
• Radiometric Dating: The process of determining the age of rocks by measuring the amount of radioactive decay.
• Comparative Anatomy: refers to the similarities and differences in structures of species.
• Three types of comparative anatomy:

  Homologous structures

  Analogous Structures

  Vestigial structures
• Analogous structures are body parts that perform similar functions, but did not evolve from a common ancestor.
• Homologous structures are body parts that have evolved from common ancestors, but now serve different functions.
• vestigial structures are structures that have lost their function but are still present in the body
• Embryonic development is the process of development of an embryo from fertilization to birth. Many organisms have similar embryo which supports the ideas of common ancestor.
• Genetic information small changes in DNA that causes evolution
• Five fingers of evolution:

  • Population can shrink
  • Mating
  • Mutation
  • Movement
  • Adaptation