Master The Living World: Biodiversity with AP Environmental Science review games.
This unit covers species diversity, ecosystem services and island biogeography — essential concepts for AP Environmental Science. Use our interactive study games to test your understanding, or review questions in traditional format below.
Pick a mode. Play.
Answer questions as fast as you can. 2 minutes on the clock. Build streaks for bonus points!
Don't want to play?
Review the questions traditionally. Click to expand.
Questions loading...
Focus on understanding.
Focus on understanding core concepts before memorizing details. Use the game modes to test yourself repeatedly — spaced repetition is proven to boost long-term retention.
Ready for college?
See which colleges accept your AP Environmental Science score.
This unit covers species diversity, ecosystem services and island biogeography — essential concepts for AP Environmental Science. Use our interactive study games to test your understanding, or review questions in traditional format below.
Key Concepts Breakdown
1 Species Diversity
Species diversity has two components: species richness (the number of different species in an area) and species evenness (how equally individuals are distributed among species). Higher species diversity generally increases ecosystem stability and resilience. The AP exam tests your ability to calculate and interpret the Shannon Diversity Index and compare diversity across ecosystems.
Key Points
- Species richness = total number of species; species evenness = relative abundance of each species
- A community with high richness but low evenness (one species dominates) has LOW overall diversity
- Keystone species have a disproportionately large effect on biodiversity relative to their abundance
- Genetic diversity within a species buffers against disease and environmental change (e.g., cheetah bottleneck)
Community A has 4 species with individuals distributed 25/25/25/25. Community B has 4 species distributed 97/1/1/1. Which community has greater species diversity?
Both communities have the same species richness (4 species), so richness alone does not distinguish them. Community A has near-perfect evenness, meaning all species contribute equally to the community structure. Community B is dominated by one species, giving it very low evenness and therefore significantly lower overall species diversity despite identical richness.
2 Ecosystem Services
Ecosystem services are the benefits that healthy ecosystems provide to humans, categorized as provisioning, regulating, cultural, and supporting services. The AP exam expects you to classify specific services into these categories and explain the consequences of biodiversity loss on service provision. Economic valuation of ecosystem services (e.g., natural capital) is also tested.
Key Points
- Provisioning services: food, fresh water, timber, medicine — direct goods extracted from nature
- Regulating services: climate regulation, flood control, water purification, pollination
- Cultural services: recreation, spiritual value, ecotourism — non-material human benefits
- Supporting services (foundation): nutrient cycling, soil formation, primary production — enable all other services
A coastal wetland is drained to build a resort. Identify two ecosystem services lost and predict one measurable consequence for the local human community.
The wetland provided flood/storm surge buffering (regulating service) and water filtration (regulating service). Without the wetland, the surrounding area faces increased flood damage during storms and higher costs for municipal water treatment. This is a classic exam scenario requiring students to link service loss to a concrete human impact rather than just naming the service.
3 Island Biogeography
The theory of island biogeography (MacArthur and Wilson) predicts species richness on islands based on two opposing rates: immigration (colonization) and extinction. At equilibrium, these rates balance to produce a stable species number. The AP exam heavily tests how island size and distance from the mainland shift these curves and change the equilibrium species number.
Key Points
- Large islands have lower extinction rates (more habitat, larger populations) → higher equilibrium species richness
- Near islands have higher immigration rates (easier colonization) → higher equilibrium species richness
- The equilibrium is dynamic: species composition changes even when total number stays constant (species turnover)
- This theory applies to habitat islands (forest fragments, nature reserves) — central to conservation biology
Island X is large and close to the mainland. Island Y is small and far from the mainland. Compare their immigration curves, extinction curves, and predicted equilibrium species richness.
Island X has a high immigration rate (close proximity lowers dispersal barrier) and a low extinction rate (large area supports larger populations), so its equilibrium point — where the two curves intersect — occurs at a high species number. Island Y has a low immigration rate and a high extinction rate, shifting its equilibrium to a much lower species number. On an exam graph, you would draw X's extinction curve below Y's and X's immigration curve above Y's, with the intersection (equilibrium) for X plotted further right on the x-axis.
Questions, answered.
What is The Living World: Biodiversity?
The Living World: Biodiversity is Unit 2 of AP Environmental Science, covering species diversity, ecosystem services and island biogeography.
How to study for AP Environmental Science Unit 2?
Start with the Quick Summary above, review the Key Concepts, then test yourself with our interactive study games. Aim for 80%+ accuracy before moving on.
How many questions are in this unit?
This unit has 25+ review questions across 5 different game modes.