Biodiversity Flashcards
Define species richness
Number of species within an ecosystem
How can biodiversity be measured? (3)
- number and range of different ecosystems and habitats
- number of species and their relative abundance
- Genetic variation within each species
Define biodiversity
Measure of variety of living organisms within a particular habitat, ecosystem or biome
What does it mean when an ecosystem has a high species diversity?
High diversity: The ecosystem is more stable and resilient to environmental changes
Define genetic diversity
Diversity of alleles and genes in the genome of a species
Define endemism and the risk with it
Where a species can only occur in one area of the world
Risk: extinction due to their limited range as they don’t naturally occur anywhere else
Why has the human population grown exponentially? (2)
- Improved technology- abundance of food= increased birth rate
- Improved medicine, hygiene and health care= decreased death rate
What are the main factors affecting biodiversity? (5)
- Habitat destruction
- Overexploitation
- Hunting
- Agriculture
- Climate change
Define diversity index
Measure of the relationship between number of species present and how each species contributes to total number of organisms present in that community
Define habitat
Place where a species lives within an ecosystem
Define niche
Role that a species plays within its habitat. Every species has a unique niche
What happens when 2 species try to occupy the same niche?
They will compete for same resources leading to successful species outcompeting the other until 1 is left
Define adaptations
Features of an organism that increase their survival and reproduction chances
What are anatomical adaptations?
Structural features: horns, claws, feathers etc.
What are behavioural adaptations?
Behaviours: courtship, defence etc.
