topic 1 Flashcards
biodiversity
variety of life on earth
identified/estimated species
2 million identified, 5-100 million (8.7) estimated/to be discovered
main components of biodiversity
genetic diversity, species diversity, ecosystem diversity
genetic diversity
genetic variation within/between populations of a single species
population
group of individuals in a species that live in the same area and interbreed to create fertile offspring
species diversity
variety of species within a region/habitat
threats to species diversity
human activities: habitat and pollution
ecosystem diversity
variety of different habitats within a region
benefits to biodiversity
provisioning services, regulating services, supporting services, cultural services
provisioning services
products humans directly obtain from natural sources
how does species diversity benefit humans (example)
more species = more genetic diversity = more potential areas where humans can benefit (rosy periwinkle for anti-cancer drugs)
regulating servies
benefits beyond raw materials: climate regulation, water/air purification
supporting services
biosphere viability: oxygen production, CO2/biomass/water cycling
cultural services
non-material benefits: recreational, aesthetic, spirtual
extinction
no more living species on earth
extant species
species that have living members
extirpation
regional loss of a species
how do humans threaten biodiversity
habitat loss, invasive species, overexploitation, climate change
pushing species towards extinction, development reducing ecosystem diversity (coral reefs, aral sea)
effects/examples of habitat loss
loss of biodiversity through habitat loss/fragmentation
amazon rainforest fires, extirpation of swift fox, black-footed ferret, greater prairie chicken
invasive/introduces species
species that are introduced to areas otuside of their native range, potentially causing environmental/economic/social damages
examples of invasive speices
brown tree snake in guam extirpating native birds, zebra mussels in great lakes from ballast water
overexploitation
overharvesting of plants and animals (unsustainable rates), most effect on low reproductive rates
climate change (biodiversity threat)
warmer temperatures, altered precipitation patterns, extreme weather events changing ecosystems faster than species can adapt
