Biology Flashcards: Analyze Biodiversity Data

What this deck covers

This deck focuses on Analyze Biodiversity Data, giving you a quick way to review the definitions, rules, and examples that matter most for Biology.

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: What is a common interpretation if sensitive indicator species decline in a dataset?

Answer: Environmental quality is likely worsening (for example, pollution increasing). Declining sensitive species suggests habitat degradation.

Flashcard 2: What is the difference between correlation and causation when analyzing biodiversity data?

Answer: Correlation is association; causation means one factor produces the change. Correlation shows pattern; causation proves mechanism.

Flashcard 3: What is a confounding variable in a biodiversity field study dataset?

Answer: An uncontrolled factor that affects the response and is linked to the predictor. Hidden variable influences both predictor and response.

Flashcard 4: What is the key assumption when using a transect to compare diversity across a gradient?

Answer: Sampling points are consistently spaced and represent the gradient. Systematic sampling accurately reflects environmental changes.

Flashcard 5: Find $p_i$: a species has $n_i = 8$ individuals out of $N = 40$. What is $p_i$?

Answer: $0.2$. Divide individual count by total sample size.

Flashcard 6: Which option best describes why two communities can have equal richness but different diversity?

Answer: They can differ in evenness despite having the same richness. Evenness affects diversity independently of richness.

Flashcard 7: What is species evenness in biodiversity analysis?

Answer: How evenly individuals are distributed among species. Measures how balanced abundance is across species.

Flashcard 8: What is relative abundance for species $i$ in a sample?

Answer: $p_i = \frac{n_i}{N}$. Proportion of species $i$ out of total individuals.

Flashcard 9: What does abundance mean in a biodiversity data table?

Answer: The number of individuals of a species in the sample. Raw count of organisms for each species.

Flashcard 10: Which option best describes why two communities can have equal richness but different diversity?

Answer: They can differ in evenness despite having the same richness. Evenness affects diversity independently of richness.

Flashcard 11: What is a keystone species and why is it important in biodiversity interpretation?

Answer: A species with large ecosystem impact; its loss can reduce diversity. Disproportionate ecological influence maintains community structure.

Flashcard 12: What is an indicator species in environmental monitoring datasets?

Answer: A species whose presence or abundance reflects environmental conditions. Abundance changes signal environmental health changes.

Flashcard 13: What is the role of replication when comparing biodiversity between two habitats?

Answer: It reduces random error and increases confidence in differences observed. Multiple samples distinguish real patterns from chance.

Flashcard 14: What is the difference between accuracy and precision in biodiversity measurements?

Answer: Accuracy is closeness to true value; precision is consistency of repeats. Accuracy measures correctness; precision measures repeatability.

Flashcard 15: Calculate richness: a site has species counts A:5, B:0, C:2, D:1. What is richness?

Answer: 3 species. Count species with abundance greater than zero.

Flashcard 16: Find $p_i$: a species has $n_i = 8$ individuals out of $N = 40$. What is $p_i$?

Answer: $0.2$. Divide individual count by total sample size.

Flashcard 17: Calculate percent composition: $n_i = 12$ and $N = 60$. What percent is species $i$?

Answer: $20\%$. Multiply relative abundance by 100 for percentage.

Flashcard 18: Identify the more even community: A has counts $25,25,25,25$; B has $70,10,10,10$.

Answer: Community A. Equal abundances create maximum evenness.

Flashcard 19: Which community has higher richness: A has 6 species; B has 4 species. Choose one.

Answer: Community A. Richness is simply the count of species present.

Flashcard 20: Compute $\sum p_i^2$ for two species with $p_1 = 0.5$ and $p_2 = 0.5$.

Answer: $0.5$. Square each proportion and sum the results.

Flashcard 21: What is species richness as used in biodiversity datasets?

Answer: The number of different species present in a defined area. Simply counts distinct species without considering abundance.

Flashcard 22: What is species evenness in biodiversity analysis?

Answer: How evenly individuals are distributed among species. Measures how balanced abundance is across species.

Flashcard 23: What is the key assumption when using quadrat sampling to estimate plant diversity?

Answer: Quadrats are representative and placed using an unbiased method. Random placement captures true community diversity patterns.

Flashcard 24: What is a common sampling bias that can reduce observed species richness?

Answer: Insufficient sampling effort or unequal detectability among species. Undersampling misses rare or hard-to-detect species.

Flashcard 25: What is biodiversity in the context of analyzing ecological data?

Answer: Variety of life measured across genetic, species, and ecosystem levels. Includes all forms of life variation across three hierarchical levels.

Flashcard 26: Compute Simpson diversity $1-\sum p_i^2$ for $p_1 = 0.5$ and $p_2 = 0.5$.

Answer: $0.5$. Subtract the sum of squared proportions from one.

Flashcard 27: Compute $\sum p_i^2$ for $p = 0.8$ and $0.2$ (two species).

Answer: $0.68$. Calculate: $(0.8)^2 + (0.2)^2 = 0.64 + 0.04$.

Flashcard 28: Compute Simpson diversity $1-\sum p_i^2$ for two species with $p = 0.8$ and $0.2$.

Answer: $0.32$. Apply formula: $1 - 0.68 = 0.32$ for diversity.

Flashcard 29: Identify the correct conclusion: if richness is constant but $H$ increases, what changed?

Answer: Evenness increased. Higher diversity with constant richness means better evenness.

Flashcard 30: Choose the correct inference: two sites share few species; is beta diversity high or low?

Answer: High beta diversity. Few shared species indicates high species turnover.