Every question about loss, disturbance or recovery is an application of that, and the tool below builds questions from your notes.
WeSolve+ reads the whole document and writes the questions for you
Upload your PDF, photograph your notebook, or point the camera. WeSolve+ writes questions from that material, explains why each answer is right, reads the chapter back to you as a podcast, and remembers every item you missed until you own it.
The tool below is a small browser-only tool and it is not WeSolve+: paste a few lines and text rules turn them into cards on the spot. The real app, the one that uses AI, is behind the link above.
Biodiversity terms, from your notes
This is a browser-only tool, and that is all it isIt splits the text you paste by rule, and nothing else. WeSolve+ is a different thing entirely: it reads your whole PDF with AI, writes the reasoning behind every question, speaks the chapter back to you, and remembers what you missed so it can return it. Try the real app now, free!
This tool splits the text you paste by rule and returns cards. It cannot read a diagram, so photograph any succession diagrams into the app rather than into this box.
Richness and evenness measure different things
Two communities can hold the same number of species while one is dominated by a single organism and the other is balanced. Richness counts kinds; evenness describes distribution. Questions that give you two communities and ask which is more diverse are testing whether you noticed the second.
Genetic diversity is where resilience actually lives
A population where every individual is nearly identical faces a new disease with one response. Variation within a species means some individuals may already carry what the new conditions require. That is the mechanism behind the whole insurance framing, and it explains why small isolated populations are fragile.
Keystone species are defined by disproportion
A keystone species matters far more than its abundance suggests, which is why removing one can restructure a whole community. The word is not a synonym for important or common, and questions frequently offer an abundant species as a distractor to see whether the definition is precise.
The two successions differ by one thing: soil
Primary succession starts where there is none and must build it, which is why it takes far longer. Secondary succession starts with soil already present and often with a seed bank in it. Naming soil as the difference answers most succession questions in one clause.
Specialists and generalists respond to change differently
A narrow set of requirements is efficient while conditions hold and dangerous when they shift. That trade-off explains why disturbance so often favours generalists and why specialists appear disproportionately on threatened lists. Questions about a changing habitat almost always want that comparison rather than a species name.
What to photograph for The Living World, Biodiversity
Diagrams, because the arrows carry the meaning in this subject. Related: Unit 1, photo to quiz and pricing.
Sources used on this page
- College Board, AP Environmental Science
- Biodiversity
- Species richness
- Keystone species
- Ecological succession
- Active recall
- Spaced repetition
- Testing effect
- Forgetting curve
- Generation effect
- Judgment of learning
- Metacognition
- Desirable difficulty
- Distributed practice
- Formative assessment
- Flashcard
- Cloze test
- Multiple choice
- Test (assessment)
- Educational assessment
- Advanced Placement
- Curriculum
- Study skills
- Study guide
- Note-taking
- Overlearning
- Instructional scaffolding
- Item analysis
- Mastery learning
| Term | What it counts | Why it matters |
|---|---|---|
| Species richness | Number of species | A first, crude measure |
| Species evenness | Distribution among them | Two equal counts can differ |
| Genetic diversity | Variation within a species | Where resilience lives |
| Keystone species | Disproportionate effect | Removal restructures |
| Specialist | Narrow requirements | Efficient, then fragile |
| Generalist | Broad requirements | Favoured by disturbance |
What is AP Environmental Science Unit 2?
The Living World, Biodiversity: species and genetic diversity, ecosystem services, disturbance, succession and the effects of loss.
What is the difference between richness and evenness?
Richness counts how many species are present. Evenness describes how individuals are distributed among them, so two communities with equal counts can differ sharply.
Why does genetic diversity matter so much?
Because a population of near identical individuals has one response to a new pressure. Variation means some may already carry what the new conditions require.
What makes a species a keystone?
An effect out of proportion to its abundance. It is not a synonym for common or important, and questions often offer an abundant species as a distractor.
How do primary and secondary succession differ?
By soil. Primary succession starts with none and must build it, which takes far longer. Secondary starts with soil and often a seed bank already present.
Why are specialists more vulnerable?
Because narrow requirements are efficient while conditions hold and dangerous when they change, which is why disturbance tends to favour generalists.
Last updated: 2026-08-15