Unit 2 Quiz 2 - Test 2 Flashcards
everything between those two.
Why is preserving genetic diversity important?
populations w low GD are not well suited to surviving environmental change
major concerns about declining Genetic diversity in ___ and ___ species
crops, livestock
we are in the middle of earth’s ___ mass extinction
sixth
some degree of extinction occurs _____, due to?
naturally
due to competition, chance events, and or natural disasters
endangered species?
in danger of extinction in foreseeable future throughout all or a significant portion of its range
Threatened species?
likely to become endangered within foreseeable future
across all groups of organisms assessed, nearly ___ are threatened w extinction
1/3
Causes of extinction? Name at least 5
habitat loss
climate change
pollution
overharvesting
invasive species
poaching/illegal trade
The Endangered Species Act of 1973
provides a framework to conserve and protect endangered species and threatened species and their habitats both domestically and abroad
habitat loss as it relates to extinction
supports smaller populations, decreases genetic diversity
competitive pressures within or between species rises
insufficient habitat variation
restricts movement and migratory patterns
habitat fragmentation as it relates to extinction
-in addition to habitat loss issues
reduces gene flow
more “edges” which present challenging conditions and predator vulnerability
introduction of invasive species as it relates to extinction
spread rapidly and cause harm across large areas
threaten biodiversity by acting as a novel predator and novel pathogens,
and/or superior competitors to natives
overharvesting as it relates to extinction
occurs when indivudals are removed at a faster rate then replenished
example: american bison (99.99% dead)
poaching and illegal trade as it relates to extinction
despite extensive laws, ilelgal poching adn trade still occur around the world
parts are harvest for “medicinal value” fur trade, exotic pets, and rare animals
pollution as it relates to extinction
air and water pollutants threaten many species
climate change as it relates to extinction
can contribute to habitat loss
some species cannot adapt to the changes better than other depending on factors like:
gene diversity and pop size
alternative habitat availability and ability to migrate
generational time
breadth of niche
how to we protect threatened and endangered species?
conserving or restoring habitat
well-regulated hunting of other species in community
craock down on poaching and trafficking
encourage captive breeding
ecosystems have ___ value and ___ value which means
intrinsic, means they have value just by existing
instrumental: value from goods and services they provide
an ecosystem approach to conserving biodiversity recognizes:
benefit of preserving particular regions of world, such as biodiversity hot spots
considerations for designating protected areas
better to protect one large area or many small areas?
larger habitats support larger pops and greater species div. smaller areas provide insurange
should protected areas be isolated or located in proximity to other protected areas?\
when they are far apart, less likely species can travel among them but also less likely areas will all be affected by disaster.
habitat corridors?
maintain a degree of connectedness that can be opened or closed as appropriate
climate change effects on temperature in respect to consequences of climate change
global temps are expected to rise 1.8–>4C by 2100
expect more heat waves and fewer cold spells
climate change effects on precip in respect to consequences of climate change
more erratic precip around globe, more extreme droughts and floods
climate change effects on storms and natural disasters in respect to consequences of climate change
storm intensity is already increasing, with temp rise, precip rise, and warmer ocean currents
will continue to rise
climate change effects on vectors in respect to consequences of climate change
temp rising, rainfall rising, and cold spell decreases have increased geographical range and or seasonal duration of pathogens and associated vectors (e.g. mosquitoes)
climate change effects on ice, snow, and glaciers in respect to consequences of climate change
polar ice and snow, glaciers, and permafrost layers have already began rapidly melting.
Initiates + loops
causes habitat loss
reduces ground water recharge
contributes to sea level rise
climate change effects on sea level rise in respect to consequences of climate change
caused by increased ice melt and thermal expansion due to ocean warming
can contribute to:
saltwater intrusion: movement of saltwater into coastal freshwater aquifers
extreme flooding or loss of coastal land area
climate change effects on ocean currents in respect to consequences of climate change
may shift as sea level rises due to salinity changes from glacier melt and rainfall increase, further altering climate and ocean food webs of nearby continents
climate change causes shifts in phenology which means
cyclic and seasonal natural phenomenon do not sync up across species in a given community.
ex: spring lead index changes, phenological mismatch of pied flycather and caterpillars)
major threats to human health and well-being
food insecurity
displacement
increased incidence of heat related deaths
reduced access to drinking water
increased pathogen exposure
