AP BIO Chapter 56

What is conservation biology
intergrates ecology, physiology, molecular biology, genetics, and evolutionary biology to conserve diversity at all levels

Explain the difference between endangered species and threatened species
Endangered species: in danger of extinction throughout all or a significant portion of its range
Threatened species: those that are considered likely to become endangered in the near future

What do conservation biologists who adopt the small-population approach study
the processes that cause extinctions once population sizes have been severely reduced

Explain what an extinction vortex is, and describe one field study that supports this idea
The loss of the genetic variation that enables evolutionary responses to environmental change, such as the appearance of new strains of pathogens

Why is genetic variation the key issue in the small-population approach
it enable evolutionary responses

On what type of population does the declining-population model focus
threatened and endangered populations that show a downward trend

What is the emphasis for study in the declining population model
the environment tractors that caused a population decline in the first place

Describe how the increase in cowbirds is related to forest fragmentation
Because cowbirds need forests, where can parasite the nests of other birds, and open fields where they forage on insects. Their populations are growing where forests are being cut and fragmented, creating more edge habitat and open land

What are potential positive and negative effects of movement corridors
+ They can promote dispersal and reduce inbreeding in declining populations
Increase the change exchange of individuals among populations of many organisms

– They allow the spread of disease
They facilitate the movement of disease-carrying ticks

Explain the concept behind a zoned reserve
It is to develop a social and economic climate in the surrounding lands that is compatible with the long-term viability of the protected core

Define critical load
the amount of added nutrient, usually nitrogen or phosphate, that can be absorbed by plants without damaging ecosystem integrity

What did Rachel Carson accomplish with her writings
she helped bring the problem to public attention in the 1960’s, and DDT was blamed in the US in 1971

Explain the concept behind the phrase sustainable development
an economic development that meets the needs of people today without limiting the ability of future generations to meet their needs

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