IB Environmental systems and societies Topic 3: Conservation and Biodiversity Key Definitions

Adaptation is a heritable trait that increases an organism’s chances of survival and reproduction in a particular environment.

Anthropocene means “the age of humans”, emphasizing the unprecedented role humans play in altering Earth’s geology, atmosphere, and biosphere.

Artificial selection, unlike natural selection, is a human-driven process in which specific traits are chosen for breeding in plants and animals.

Biodiversity refers to the variety of life in an ecosystem, encompassing different levels of biological organization.

A biogeographic region that has exceptionally high levels of species richness and endemism but is also under significant threat from human activity.

Biosphere integrity refers to the capacity of ecosystems to maintain biodiversity (genes, species, functions) and continue providing essential ecological services.

Carbon sequestration is the process of capturing atmospheric carbon dioxide (CO₂) and storing it in solid or liquid form.

Citizen science is the involvement of the general public in scientific research, particularly in collecting, analyzing, and reporting data on environmental systems.

A critical threshold is the moment at which a system crosses a boundary, triggering rapid state change.

Ecosystem resilience refers to an ecosystem’s ability to recover from disturbances and return to its original state or adapt to a new equilibrium.

Endemism refers to species that exist only in one geographic location, such as an island, mountain range, or isolated ecosystem.

Evolution is the cumulative change in the heritable characteristics of a population over generations.

Fossils are preserved remains, traces, or imprints of ancient organisms found in sedimentary rocks.

Genetic diversity is the variety of genes within a species, allowing for adaptation to environmental changes.

Genetic recombination refers to the random mixing of parental genes during meiosis and fertilization, creating genetically unique offspring.

Habitat diversity is the range of different habitats present in an ecosystem or within a geographical area.

Invasive alien species are non-native organisms that, when introduced to a new ecosystem, can cause significant harm to local biodiversity.

The International Union for Conservation of Nature (IUCN) is the global authority on the conservation status of species.

Key Biodiversity Areas (KBAs) are sites that have been prioritized for conservation due to their exceptional ecological value.

A keystone species is an organism that has a disproportionately large impact on its ecosystem relative to its population size.

Microplastics are small plastic particles, typically less than 5 millimeters in diameter, that result from the breakdown of larger plastic waste or are intentionally manufactured at that size.

A mutation is a random change in DNA that introduces new genetic variants (alleles).

Natural selection is the primary mechanism behind evolutionary change, shaping species over time and leading to the incredible biodiversity we see on Earth today.

Nutrient cycling is the movement of nutrients like nitrogen, phosphorus, and carbon through the soil, plants, and atmosphere.