Unit 3 ESS

• Biodiversity is a quantifiable version of nature that helps policy-makers in suggesting what to do, making better science.
• There are three different types of biodiversity: Genetic diversity, species diversity and habitat diversity.
• Species diversity is the product of two variables - number of species and relative proportions.
• Genetic diversity is the range of genetic material present in a gene pool and the amount of variation that exists between different individuals within different populations of a species.
• The 2nd law of thermodynamics states that entropy, which is the unavailability of a system’s thermal energy for conversion into mechanical work, increases with time.
• Most ecosystems are very complex and can withstand stress better, making them a more stable system.
• Approaches to conservation include human health, human rights, recreational, ecotourism, and ethical/intrinsic value.
• The amount of disorder in a system is represented by entropy.
• Gene/Seed banks are used to maintain genetic diversity for plants.
• Balance is a required in the system.
• Monoculture farming is very simple and open to pests and diseases, increasing vulnerability.
• Non-living things are static in steady state equilibrium.
• Equilibrium is very important in a system.
• Steady state equilibrium is when the human body sweats to cool down and shivers to heat up to maintain a steady body temperature.
• Organisms reverse entropy, according to the 3rd law of thermodynamics.
• More entropy in a system means less order.
• Complex systems tend to fail.
• A keystone species is a species that has a disproportionately large effect on its natural environment relative to its abundance, with examples including krill, beavers, bees, tuna, sea otters, and elephants.
• Humans can speed up speciation by artificial selection of animals.
• Physical barriers such as large flightless birds, marsupials, placental mammals, and cichlid fish, occur on continents that made up "Gondwana" - Africa, Australia, New Zealand, South America.
• Tropical rainforests are hotspots, occupying 6% of land but containing high biodiversity.
• Land bridges allow species to invade new areas and may result from lowering of sea levels instead of continental drift.
• Habitat diversity is the range of different habitats per unit area in a particular ecosystem or biome.
• Plate activity influences biodiversity through convergence, divergence, and sliding.
• Tropical rainforests are vulnerable because they upset the equilibrium due to deforestation and have imbalanced flows of nutrients due to palm oil extraction in Indonesia.
• Hotspots are regions with high level of biodiversity that are under threat from human activities, including ten in tropical rainforests, near to tropics with fewer limiting factors in lower latitudes, cover only 2.3% land surface, threatened areas where 70% of the habitat is lost, tend to have large human habitations nearby, and contain more than 1,500 plant species that are already endemic.
• Charles Darwin's theory of evolution, "The Origin of Species" (1859), discusses speciation, the gradual change of species over a long time.
• Habitat with high biodiversity has advantages such as resilience and stability, but also disadvantages like managing grazing can be difficult due to tolerance differences between plant species.
• Speciation occurs when the population of the same species are separated and cannot interbreed if the inhabited environment changes.
• Factors maintaining biodiversity include the complexity of the ecosystem, stage of succession, limiting factors, and inertia, the property of an ecosystem to resist change when subjected to a destructive force.
• Natural hazards, loss of habitat, and fragmentation of habitats are factors leading to a loss of biodiversity.
• The background extinction rate is the natural extinction rate of all species, approximately one species per million species per year.
• Natural products, such as honey, oil palms, and guano, are derived from biodiversity.
• The spread of diseases, like Ebola in 2014/15 and Swine Flu in 2010, which are endemic in pigs and birds, are a threat to biodiversity.
• Modern agricultural practices, like monocropping, can be less destructive to biodiversity.
• Narrow geographical range, small population, declining population, low population density and large territory, few population of species, large body, low reproductive rate, seasonal migrates, poor dispersers, specialized feeders, hunted for food/sport, and minimal viable population size are factors that make a species prone to extinction.
• The International Union for Conservation of Nature and Natural Resources (IUCN) Red List determines the conservation status of a species based on criteria, which include extinct, critically endangered, endangered, vulnerable, least concerned, data deficient, and not evaluated.
• Introducing exotic/non-native species can work sometimes, like potatoes from Americas to Europe, but sometimes not, like Rhododendrons introduced to Europe from Nepal which escaped into the wild and outcompete native plants and are toxic.
• The Dodo Bird and the Tasmanian Tiger are examples of extinct species.
• Conserving biodiversity provides economic, ecological, social, aesthetic (PECe) value, including food sources, scientific and education value, biological control agents, gene pool, recreational, ecotourism, ethical/intrinsic value, and environmental services.