Biodiversity G9

• Biodiversity is the variety of life on Earth, including all living organisms.
• What is the sixth extinction called?


  Holocene extinction
• The five past major extinctions have been natural
• The sixth extinction is due to human activity
• The holocene extinction is to be the largest in our planets history
• Extirpated is being extinct in a particular region
• Endangered means being at risk of becoming extinct
• Threatened: Risk of becoming endangered
• Bioindicator species are species that help indicate environment change
• Human impact has wiped out many of the species
• Zoos preserve biodiversity of animals
• Seed banks preserve biodiversity of plants
• How zoos preserve biodiversity 


  Exchange animals, initiates and supports research, genetic diversity is essential
• How seed banks preserve biodiversity


  Collect seeds, store seeds from plants that are threatened with extinction, agricultural and research purposes
• The preservation of biological diversity depends on both local efforts and global cooperation. Global treaties have been drawn up to protect endangered plants and animals.
• Evolution: The way in which living things change and develop over time (millions of years) through development of new species
• What is a domestic animal

  An animal that is no longer wild and has been bred or tamed by humans to perform various functions
• Artificial selection is also called

  Selective breeding
• Artificial selection is the

  Technique in which individual plants or animals with desirable traits are bred together to develop plants or animals with specific traits
• Artificial selection has human interference
• Natural selection occurs naturally
• Natural selection is the

  Process in which only those organisms with the best traits for survival in an environment survive to reproduce; over time this process results in changes in the genetic characteristics of a species
• Through selective breeding, we can actually produce offspring with desired traits that would not necessarily have an advantage in nature.
• Example of Artificial selection in animals

  Dairy cow, beefalo
• In agriculture, scientists use selective breeding to bring the positive characteristics of two different varieties together
• How is natural selection different from artificial selection


  Natural selection is done by organisms/nature and artificial selection is done by humans breeding plants
• Although artificial selection and genetic engineering both involve human interference, they are different
• Advantage of selective breeding

  Produces animals with specific desirable traits that humans want
• Disadvantage of selective breeding

  Decreased variation, can bring out harmful recessive traits
• Theory of natural selection - Proposed by Charles Darwin in 1859

  1. All organisms produce more offspring than can possibly survive
  2. There is incredible variation within each species
  3. Some of these variations increase the chances of an organism surviving to reproduce
  4. Over time, variations that are passed on lead to changes in the genetic characteristics of a species
• Similarity of natural section and artificial selection

  • Traits are inherited from parents
  • Results in change in genetic traits of a species
  • Change occurs over many generations
• Natural selection is one method that drives evolution to happen.
• A niche is the role of an organism within an ecosystem
• Niche = where it lives + what it does
• Niche

  1. Habitat: Physical & environmental conditions (i.e. temperature) that species is living in
  2. Interactions with other species
• Broad Niche

  • Generalists
  • Less species and larger populations
  • Good ability to adapt to changes
  • Ex: Raccoons, coyotes, bobcats
• Narrow Niche

  • Specialists
  • More species and smaller populations
  • Poor ability to adapt to changes
  • Ex: Koala, pandas, Cactus
• Specialists are more at risk for endangerment/extinction compared to generalists
• Competition can be between members of the same species or between different species for resources
• Competition example

  Birds feeding on trees