evolution

• Evolution

  Occurs when heritable characteristics of a species change
• selective breeding

  • Developed from wild species by selecting individuals with desirable traits and breeding from them
• Speciation

  • Populations have evolved into separate species
• Groups of vertebrates

  • Amphibians
  • Birds
  • Reptiles
  • Mammals
• Vertebrates

  • Share an ancestor and have a basic bone structure
  • Many groups have evolved through adaptive radiation
• fossil records as evidence for evolution

  • Rocks can be dated to determine the age of fossils
• heritability and evolution

  Characteristics that are not heritable so are lost when the individual dies
• natural selection

  Charles Darwin- survival of the fittest. species produce more offspring than the environment can support. variation between individuals and Some are better adapted so pass on their characteristics to offspring
• Antibiotic resistance

  control diseases. Genes that give resistance occur in the microorganisms and are transferred so those that are resistant will not be killed and they reproduce and are passed on
• Binomial system

  First name is genus, second name is species
• Natural classification

  • Putting species into groups based on common ancestry
  • Allows prediction of characteristics
• Domains

  • Archaea
  • Eubacteria
  • Eukaryota
• Plant features

  • Bryophytes (mosses)
  • Filicinophytes (ferns)
  • Coniferophytes
  • Angiospermophytes (flowering plants)
• Vertebrate features

  • Amphibians
  • Birds
  • Bony ray-finned fish
  • Reptiles
  • Mammals
• Animal groups

  • Platyhelminthes
  • Mollusca
  • Porifera
  • Annelida
  • Chordata
  • Cnidaria
  • Arthropoda
• Clade

  A group of organisms that evolved from a common ancestor
• Cladograms

  • Tree diagrams that show the most probable sequence of divergence in a clade
• Beaks of finches vary in size and shape to feed on a wide range of seed sizes
• Large seeds are harder

  More difficult to open
• Variation in the size of beaks


  • Heritable characteristic
  • Droughts often occur
  • Few small seeds available
  • Finches with larger beaks more likely to survive
• Species identification


  Uses dichotomous key
• Dichotomous key


  1. Series of numbered stages

  2. Consist of a pair of alternative characteristics
• Taxonomic levels


  • Species
  • Genus
  • Family
  • Order
  • Class
  • Phylum
  • Kingdom
  • Domain