SCIENCE

• Carolus Linnaeus


  Developed a system of classification to group organisms by their similarities which shows something about evolution
• George Louis de Buffon


  Proposed that organisms shared common ancestors
• Erasmus Darwin


  All living things were descended from a common ancestor
• Jean Baptiste Lamarck


  All organisms evolved toward perfection and complexity, in which species evolved into different feature
• Alfred Russel Wallace


  Studied the huge diversity of plants and animals in tropic region
• Charles Darwin


  Proposed Natural Selection sometimes called as Survival of the Fittest
• Reasons for preserving biodiversity

  • Isolating unique genetic material so it can be incorporated into existing crops
  • Increasing the chances of discovering organisms with medicinal value
  • Finding new plants that can supplement the world's food supply
• Groups of organisms most in danger of extinction


  • Organisms that migrate or need special habitats
  • Small populations
• Most effective in slowing the loss of biodiversity


  Setting aside small plots of land in a variety of ecosystems such as forests, grasslands, and marshes
• Preserving entire ecosystems rather than individual species a good conservation strategy because more than one species can be saved
• Critical biodiversity hotspots


  • Islands
  • Tropical rain forests
  • Coastal areas
• Activities meant to develop sustainable forest ecosystems

  • Implement agroforestry
  • Plant 10 samplings for every tree cut down
  • Adopt a tree planting program in parks and watersheds
• Predators' role in the ecosystem

  • Compete with herbivores for food
  • Control population of its prey
  • Eradicate its prey
  • Balance environment
• Most numbered when it comes to danger of extinction

  • Small populations
  • Migrate or need special habitats
• Human activities had influenced recent extinction events: habitat destruction, poaching, introducing exotic species
• Not a reason for preserving biodiversity: preventing natural evolution
• There are between 10-50 million estimated species on Earth
• Species still unknown to modern science

  • Cataloging these species is a huge task
  • Many of these species are found in remote environments
  • Smaller species receive less attention than large organisms
• Why is it difficult to save individual species?

  • Small populations are more prone to disease
  • Inbreeding may result in genetic disorders
  • Captive species may not reproduce in the wild
• Best test to show the relatedness of two organisms

  Similarity in genomic DNA
• Genetic drift


  Similar to natural selection: both cause gene frequency changes
• Examples of biological aspects of an organism's niche


  • Food it eats
  • The way it obtains food
  • When and how it reproduces
• Increase in the greenhouse gases

  Increase in temperature
• Category of land use is increasing most rapidly that contributes to plant and animal extinction: loss of agricultural lands
• Causes a decreasing wildlife population in most of the places in our country: loss of habitat
• Ecosystem diversity


  Variety of habitats, communities and ecological processes within and between ecosystems
• Effects of illegal logging/cutting down trees

  • Deforestation
  • Loss of biodiversity
  • Fuelling climate change
  • Habitat loss and fragmentation
• Effects of forest fire/wild fire

  • Kill many animals and plants
  • Habitat loss
• Effects of road construction

  • Increased mortality of wildlife due to vehicle collisions
  • Changes in the physical and chemical environment
• Effects of dynamite fishing

  • Kills marine organisms
  • Destroys coral reefs habitats
• Effects of air pollution on wildlife

  • Disruption of endocrine function
  • Organ injury
  • Increased vulnerability to stresses and diseases
  • Lower reproductive success
  • Possible death
• Effects of pesticides on biodiversity

  • Short-term toxic effects on directly-exposed organisms
  • Long-term effects can result from changes to habitats and the food chain
• Population


  Total number of organisms belonging to the same species in a particular environment
• Population Density


  Measurement of a population per unit area
• Resistance


  Ability of an ecosystem to be self-regulating and become steady after a disturbance
• Competition


  Type of relationship in which animals struggle for limited resources such as food and habitat
• Genetic Disorder / Illnesses

  Happens when a gene mutates or changes by accident
• Biodiversity


  Variety of life forms in a particular ecosystem
• Ecosystem


  Community of organisms that live, feed and interact with the environment
• Vestigial Structure


  Structure of animals which is gradually disappearing