BIODIVERSITY Flashcards
What is biodiversity?
- The variety of living species
* The degree of nature’s variety
Why is biodiversity needed?
Allows for permanent stability of an ecosystem
What are the different levels that biodiversity is considered at?
- Habitat
- Species
- Genetic
- Species Richness
- Diversity Index
How is habitat considered in species biodiversity?
- Range of habitats
- Each may be occupied by different species
- Diverse habitats may lead to diverse species
How do diverse habitats affect species diversity?
Diverse habitats may lead to diverse species
How is species considered in species biodiversity?
Difference between species
• This could be within a habitat, or a community
• Differences could be structural or physical
• We can collect data about different species
○ This will inform species richness
What are some examples of the differences between species?
- Structural
* Physical
How are genetics used for species diversity?
Genetic variation exists within a species
• Degree of allelic variation between the members of a species
• It is good
○ Lack of variation results in a lack of ability to adapt
○ Natural selection depends on variation
What is species richness?
This is the number of different species present in a habitat
How is species richness considered in biodiversity?
• The more species present, the richer the habitat
What is a disadvantage of using species richness?
- Does not take into account number of individuals of each species.
- Not sufficient data to measure diversity alone
How is species richness recorded?
- Observe and record the species present in a habitat
- Samples should be taken
- Visual surveys should be taken, to ensure that nothing is missed
What are some advantages of using diversity indexes?
- It takes into account both species richness and evenness
- Gives an idea of the number of each species relative to population size
- Small and large populations are treated differently
What does a high index of biodiversity signify?
- Indicates a diverse habitat
- Many different species live there
- Small change to environment may only affect one species
- If this species is only small population, then only a small proportion of the habitat is effected
- Total effect on the habitat would be small
- Tends to be stable habitat
What does a low index of biodiversity signify?
- Suggests it is dominated by few species
- Small change to the environment may affect one of the major species
- Could damage or destroy the whole species
- Small change would have a very large impact on the environment
- Much less stable environment
