Syllabus concepts to know

• 3.1.1 Biodiversity is the total diversity of living systems and it exists at several levels.
• 3.1.2 The components of diversity contribute to the resilience of ecological systems.
• 3.1.3 Biodiversity arises from evolutionary processes.
• 3.1.4 Natural selection is the mechanism driving evolutionary change.
• 3.1.5 Evolution by natural selection involves variation, overproduction, competition for limited resources, and differences in adaptation that affect rates of survival and reproduction.
• 3.1.6 Speciation is the generation of new species through evolution.
• 3.1.7 Species diversity in communities is a product of richness and evenness.
• 3.1.8 Simpson’s reciprocal index is used to provide a quantitative measure of species diversity, allowing different ecosystems to be compared and for change in a specific ecosystem over time to be monitored.
• 3.1.9 Knowledge of global and regional biodiversity is needed for the development of effective management strategies to conserve biodiversity.
• 3.1.10 Mutation and sexual reproduction increase genetic diversity.
• 3.1.11 Reproductive isolation can be achieved by geographical separation or, for populations living in the same area, by ecological or behavioural differences.
• 3.1.12 Biodiversity is spread unevenly across the planet, and certain areas contain a particularly large proportion of species, especially species that are rare and endangered.
• 3.1.13 Human activities have impacted the selective forces acting on species within ecosystems, resulting in evolutionary change in these species.
• 3.1.14 Artificial selection reduces genetic diversity and, consequently, species resilience.
• 3.1.15 Earth history extends over a period of 4.5 billion years.
• 3.1.16 Earth history is divided up into geological epochs according to the fossil record.
• 3.1.17 Mass extinctions are followed by rapid rates of speciation due to increased niche availability.
• 3.1.18 The Anthropocene is a proposed geological epoch characterized by rapid environmental change and species extinction due to human activity.
• 3.1.19 Human impacts are having a planetary effect, which will be detectable in the geological record.