Module 3 and 4 Flashcards
Why is biodiversity not evenly distributed?
Tropics account for 40% but are host to 80% of the worlds biodiversity
What is allopatric speciation?
Geographic barrier
What is parapatric speciation?
Partial spatial isolation
What is peripatric speciation?
Isolation at the periphery
What is sympatric speciation?
Genetic polymorphism/reproductively isolated
What are high risk scenarios for extinction?
Narrow geographic range
One of few populations
Small population
Island habitat
What are consequences of exticntion?
Loss of biodiversity
Decrease water and air quality
Increased extreme weather events and climate change
Loss of cultures
What is the IUCN Red list?
An indicator fro the health of the world’s biodiversity
What are th top three threats to biodiversity in Australia?
- Invasive species
- Ecosystem modification
- Agriculture
What are some reasons for habitat loss?
Development
Clearing land for agriculture
Water diversion
Logging
What is a consequence of fragmentation?
Lack of movement among fragments increases inbreeding and decreased genetic diversity
What is an example of habitat loss?
Tigers have lost habitat due to palm oil production putting them in closer proximity with humans
What is habitat degradation?
When habitat conditions decline
What causes habitat degradation?
Pollution, human recreation and nutrient loading
What is resource overxploitation?
Hunting, fishing or collecting so many individuals from a species that it can no longer reproduce quickly enough
What is an example of climate change impacts on animals?
Elephants have less food as fruiting events occur less often as they need lower temperatures
What are invasive species?
Introduced or non-native species which become overpopulated
What are characteristics of invasive species?
Fast growth
Rapid reproduction
High dispersal ability
Adapt well to human modified ecosystems
What is an example of a non-invasive introduced species?
The cabomba weevil that is used to reduce the cabomba weed in Australia
What are the three scales of conservation?
Species approach
Ecosystem approach
Hotspot approach
What are distinctive species?
Species only in its genus or family
What are utilitarian species?
Species that have utility or value to people
What are keystone species?
Species that play a crucial role in the way an ecosystem functions