Chapter 47 Flashcards
(29 cards)
Levels of Biodiversity
Genetic Diversity
Species Diversity
Ecosystem Diversity
Genetic Diversity
amount of genetic variation that occurs within & between population
Species Diversity
the number & relative abundance of species in a community
Ecosystems Diversity
diversity of structure & function within an ecosystem
Hypothesis for species diversity affect on ecosystem
Diversity-stability
Redundancy Hypothesis
keystone hypothesis
idiosyncratic hypothesis
Diversity-stability Hypothesis
species rich communities are more stable than those with fewer species
Redundancy Hypothesis
most species are redundant, they take up space but do not add to diversity
Keystone Hypothesis
ecosystems function plummets as soon as biodiversity declines from its natural level
Idiosyncratic Hypothesis
ecosystem changes unpredictably as the number of species changes
Main causes for extinction
- invasive species
- direct exploitation
- habitat destruction
- global warming
- loss of genetic diversity
Invasive species
species are moved by humans from a native location to another location usually for agricultural purposes
Direct Exploitation
hunting of animals (can cause extinction)
Habitat destruction
deforestation, planting agriculture, urbanization
Global warming
human induced climate change
Loss of genetic diversity
inbreeding-health usually very poor in offspring
Global Conservation Strategies
- Megadiversity countries
- Areas rich in endemic species
- Representative habitats
Megadiversity countries
targeted b/c they have the greatest number of species (Brazil, Indonesia, Columbia)
Areas rich in endemic species
focuses on areas that have endemics or species that are only in a particular area and no where else
-focus on hot spots
Hot spots
regions that are biologically diverse and under threat of destruction
EX: rain forest
Representative Habitats
conserve representatives of all major habitats
EX: prairies
Single Species Approach
focuses on saving species that are deemed to be important
- indicator species
- umbrella species
- keystone species
- flagship species
Indicator Species
species whose status provides information on the overall health of an ecosystem
EX: corals
Umbrella Species
protecting them would protect many other species existing in the same habitats
EX: northern spotted owl
Keystone Species
species within a community that have a special role
EX: beavers alter community by building dams