Unit 2: The Living World – Biodiversity

Biodiversity

The variety of life in all forms, including species diversity, genetic diversity, and ecosystem diversity.

Species Diversity

The number and abundance of species in an ecosystem, combining richness (number of species) and evenness (relative abundance).

Genetic Diversity

Variation in DNA among individuals in a population, essential for adaptation and resilience.

Habitat Diversity

The range of different habitats in an area, supporting a variety of species.

Bottleneck

A sharp reduction in population size, reducing genetic diversity and potentially leading to extinction

Generalist

Species with broad diets and habitats

Specialist

Species that rely on specific conditions or food sources

Theory of Island Biogeography

Predicts biodiversity based on island size and distance from the mainland; larger and closer islands have more species.

Invasive Species

Non-native species that disrupt ecosystems by outcompeting native organisms

Range of Tolerance

The range of environmental conditions (e.g., temperature, pH) an organism can survive.

Primary Succession

Colonization of a lifeless area (e.g., after lava flow) by pioneer species like mosses and lichens.

Secondary Succession

Recovery of an ecosystem where soil remains (e.g., after a fire or farming).

Pioneer Species

Hardy species that colonize an area first, starting ecological succession.

Climax Community

A stable, long-lasting ecosystem in its final stage of succession.

Keystone Species

Species with a disproportionately large impact on ecosystem structure (e.g., wolves in Yellowstone).