3.1 Introduction to biodiversity Flashcards
Species diversity
Product of the number of species (richness) and their relative proportions (evenness)
Habitat diversity
the range of different habitats per unit area in an ecosystem or biome
Genetic diversity
the range of genetic material present in a gene pool or population of a species
Biodiversity hotspot
region with high biodiversity that is under threat from human activities
Characteristics of biodiversity hotspots
- Mostly in tropical rainforests
- Nearer the tropics - good conditions
- 70% of habitats lost
- Over 1500 species of endemic plants
- Cover 2.3% of land surface
- Large areas of human habitation nearby
When comparing two similar communities, what is low diversity evidence of?
- Pollution
- Eutrophication
- Recent colonisation
- Agricultural management
Why are biodiversity investigations in a community repeated over time?
To know if changes are due to natural succession or human activity and ∴ whether conservation efforts are succeeding or not
Which type of diversity is the most important in conservation and why?
Habitat: increasing habitat diversity increases species diversity, which then increases genetic diversity
What is the Simpson’s diversity index used for?
To describe and compare similar communities
The value on its own is not useul :)
Examples of species with low genetic diversity
- Grey seal
- Cheetahs
Examples of species with high genetic diversity
- Humans
- European red fox
Why do species with a single population in one place have low genetic diversity
Same climatic conditions, no variation
Advantages of high biodiversity
- Resilience and stability: resisting drought, disease, etc
Example of biodiversity hotspot
Atlantic forest, Brazil
Criticisms of hotspots
- Focus on vascular plants;ignore animals
- Focus on where habitats have been lost instead of places losing them
- Do not represent total species diversity or richness
- Do not consider the value of services.
