AP Biology Unit 8 Topic 5: Biodiversity

What to Know

Genetic diversity can help populations adapt to changing conditions.
Species diversity can stabilize food webs and ecosystem processes.
Human activities can reduce biodiversity through habitat loss, overuse, pollution, invasive species, and climate change.
Always connect this topic back to the larger unit: Ecology.

Detailed Notes

Biodiversity belongs to Unit 8: Ecology. Biodiversity includes genetic, species, and ecosystem variety, and it supports resilience and ecosystem function. Treat the topic as a relationship between structure, process, evidence, and biological function instead of memorizing an isolated definition.

Key relationships: Genetic diversity can help populations adapt to changing conditions. Species diversity can stabilize food webs and ecosystem processes. Human activities can reduce biodiversity through habitat loss, overuse, pollution, invasive species, and climate change.

Model to use: Compare two ecosystems by considering species richness, relative abundance, habitat variety, and genetic variation. A clear model should label the parts, show the direction of movement or information flow when relevant, and connect the diagram back to the biological outcome.

AP-style move: When asked why biodiversity matters, connect diversity to ecosystem stability, services, adaptation, or recovery after disturbance. Strong answers name the concept, apply it to the scenario, and explain the reasoning in complete sentences.

Key Vocabulary

Species richness

The number of different species in a community.

Genetic diversity

Variation in genes within a population or species.

Ecosystem diversity

Variety of habitats, communities, and ecological processes in an area.

Invasive species

A nonnative species that spreads and causes ecological or economic harm.

Conservation biology

The study and protection of biodiversity.

Habitat fragmentation

Breaking large habitats into smaller separated patches.

Quick Practice

How would you explain Biodiversity in one or two AP-style sentences?

Name the concept, apply it to a specific example or source, and explain the reasoning that connects the evidence to your answer.

Official Alignment

Reference and Attribution

Biology concept reference: Biology for AP Courses by OpenStax, Rice University. Access for free at OpenStax. Licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License. EduCompanion used this source as a conceptual reference and rewrote the study notes in original wording.