biodiversity Flashcards
What are the components of biodiversity?
The components of biodiversity are genetic diversity, species diversity, and ecosystem diversity.
What is genetic diversity?
Genetic diversity is the number and frequency of all the alleles within a population.
What happens if one population of a species dies out?
If one population of a species dies out, the species may have lost some of its genetic diversity, limiting its ability to adapt to changing conditions.
What comprises species diversity?
Species diversity comprises the number of different species in an ecosystem (species richness) and the proportion of each species in the ecosystem (relative abundance).
How does a dominant species affect species diversity?
A community with a dominant species has a lower species diversity than one with the same species richness but no particularly dominant species.
What is ecosystem diversity?
Ecosystem diversity refers to the number of distinct ecosystems within a defined area.
What is a threat to biodiversity related to exploitation?
Exploitation and recovery of populations can impact their genetic diversity.
What can happen with overexploitation of populations?
With overexploitation, populations can be reduced to a low level but may still recover.
Can species with low genetic diversity remain viable?
Some species have a naturally low genetic diversity in their population and yet remain viable.
What is the bottleneck effect?
The bottleneck effect occurs when small populations lose genetic variation necessary for evolutionary responses to environmental change.
What impact does habitat loss have on species richness?
Habitat loss leads to habitat fragmentation, which increases competition between species as fragments become smaller, potentially decreasing biodiversity.
How can habitat fragmentation be remedied?
Isolated fragments can be linked with habitat corridors to remedy widespread habitat fragmentation.
What are introduced species?
Introduced (non-native) species are those that humans have moved to new locations.
What is the impact of inbreeding in small populations?
In small populations, the loss of genetic diversity can lead to inbreeding, resulting in poor reproductive rates.
How does habitat fragmentation affect species diversity?
More isolated and smaller fragments exhibit lower species diversity.
What is the purpose of habitat corridors?
Habitat corridors allow movement of animals between fragments, increasing access to food and mate choice, potentially leading to recolonisation after local extinctions.
What are naturalised species?
Naturalised species are those that become established within new geographic locations.
What are invasive species?
Invasive species are naturalised species that spread rapidly and eliminate native species, reducing species diversity.
What factors may limit the population of invasive species in their native habitat?
Invasive species may be free of predators, parasites, pathogens, and competitors that limit their population in their native habitat.
How do invasive species impact native species?
Invasive species may prey on native species, out-compete them for resources, or hybridise with them.
