Biodiversity

• Biodiversity


  Comes from the words "biological" and "diversity"
• Levels of biodiversity

  • Genetic diversity
  • Species diversity
  • Ecosystem diversity
• Keystone species


  • A species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically
  • Not abundant in nature
  • Controls community structure by their pivotal ecological roles
  • Some limits the abundance of competitively dominant species
• Foundation species


  • Have strong effects on their communities as a result of their large size, high abundance, or pivotal role in community dynamics
  • May provide significant habitat or food for other species
• Ecosystem Engineers: create or dramatically alter physical environment, can be positive or negative
• Introduced species: invasive, nonnative, exotic species, causes ecological or economic harm where it is not native
• Introduced species: moved intentionally or accidentally from native location to new geographic region
• Republic act 9147: prohibits introduction of alien species in protected/critical habitats
• Species richness: number of different species in a community
• Species evenness/relative abundance: proportion each species represents of all individuals
• Species dominance: most abundant species
• Stability: ability to resist change in face of disturbances, biodiversity promotes stability
• Stable ecosystem increases probability of adaptation and survival in a changing environment
• Genetic diversity: variety of genes or inheritable characteristics in a population

  individual genetic variation and genetic differences associated with adptations

  increases chances of survival in changing conditions
• Ecosystem diversity: ecosystems in a biosphere, different kinds of places where organisms live and interact
• Species diversity: species concepts, variety of living things, number of different species and relative abundance
• Species concepts: typological, biological, phylogenetic
• Typological species concept: physical characteristics classifies species, description provides detailed record of physical characteristics
• Cons of typological species concept: alleles produce different traits within species
• Biological species concept: species determined by similarity of characteristics and ability to interbreed and produce a fertile offspring

  most common
• Cons of biological species concept: different species interbreed = offspring cannot reproduce
• Phylogenetic species concept: species determined by evolutionary history, accounts for extinct species and considers molecular data
• Cons of phylogenetic species concept: evolutionary history is not known for all species
• Conservation status: human intervention and an attempt to preserve critically endangered species
• IUCN (International Union of Conservation and Nature): created the red list: category of threatened species (extinct - threatened - lower risk)
• Threatened species

  Vulnerable: high risk of extinction in the wild in the medium-term future

  Endangered: very high risk of extinction in the wild in the near future

  Critically endangered: extremely high risk of extinction in the wild in the immediate future
• Vulnerable species: medium-term future, reduction of 20 percent in 10 years, exist in no more than 10 locations, less than 1000 mature individuals
• Endangered species: near future, reduction of 50 percent in 10 years, exist in no more than 5 locations, fewer than 250 mature individuals
• Critically endangered: immediate future, reduction of 80 percent in 10 years, exist in a single location, less than 50 mature individuals
• Extinct: end of species, last member dies, capacity to breed and recover is lost, no surviving individuals that can reproduce and create a new generation
• Extinct in the wild: survive only in cultivation
• Mass extinction: large numbers of species become extinct worldwide, due to habitat destruction or inability to adapt
• Habitat loss: native species relocate or die
• Habitat destruction: clearing or destruction of habitat (deforestation, filling in wetlands, dredging rivers, mowing fields)
• Habitat disruption: disruption of ecosystem processes
• Habitat fragmentation: separation of ecosystem into small pieces of land
• Edge effect: different environmental conditions occur along the boundaries of an ecosystem
• Introduced species: not a threat in native habitats, reproduce in large numbers because of lack of predators
• Overharvesting: harvesting of wild organisms at rates exceeding the ability of their populations to rebound.
• Global climate change: includes alterations in climate, atmospheric chemistry, and broad ecological systems that reduce the capacity of Earth to sustain life.