EXAM 4

Got it! Here are consolidated and clear notes based on all the provided learning objectives. They are structured for easy studying and include suggestions for visuals.

Introduction to Ecology

• Definition: Ecology is the study of interactions between organisms and their environment.

• Levels of Organization:

  • Organism → Individual living entity.

  • Population → Group of the same species in an area.

  • Community → Interacting populations.

  • Ecosystem → Community + abiotic factors.

  • Biome → Large ecosystems with specific climates.

  • Biosphere → Global ecological system.
    (Visual: Hierarchy pyramid.)

• Physical Factors Influencing Distribution:

  • Temperature, wind, water, light, salinity, and pH shape ecosystems.
    (Icons recommended for each factor.)

• Climate-Related Factors:

  • Solar Radiation: Drives temperature and weather.

  • Atmospheric Circulation: Wind and weather patterns.

  • Greenhouse Effect: Gases trapping heat to regulate Earth's temperature.

  • Global Warming: Excessive greenhouse gases causing climate change.

Population Ecology

• Population Characteristics:

  • Size: Total individuals.

  • Density: Individuals per area/volume.

  • Distribution:

    • Uniform → Evenly spaced.

    • Random → No pattern.

    • Clumped → Groups. (Visual: Example scatterplots.)

• Growth Models:

  • Exponential (J-curve): Unlimited growth.

  • Logistic (S-curve): Growth limited by carrying capacity. (Graph recommended for comparison.)

• Regulation of Population Size:

  • Density-Dependent: Affected by population size (e.g., food, disease).

  • Density-Independent: External factors (e.g., weather, disasters).

• Life Strategies:

  • r-Selected: High reproduction, short lifespan (e.g., insects).

  • K-Selected: Low reproduction, long lifespan (e.g., elephants). (Table for traits comparison.)

Species Interactions

• Types of Interactions:

  • Mutualism: Both benefit (e.g., bees and flowers).

  • Commensalism: One benefits, other unaffected.

  • Competition: Both harmed by resource use.

  • Predation: Predator-prey dynamic.

  • Amensalism: One harmed, other unaffected.

  • Altruism: Behavior benefiting others at personal cost.

• Key Concepts:

  • Ecological Niche: Role/resources of a species. (Diagram: Niche overlap.)

  • Resource Partitioning: Dividing resources to avoid competition. (Example: Birds in different tree layers.)

• Predation Strategies:

  • Camouflage, mimicry, warning coloration, chemical defenses. (Visuals of each strategy.)

• Population Control Models:

  • Top-Down: Predators limit population.

  • Bottom-Up: Resources limit population. (Food web diagram suggested.)

Community Ecology & Conservation

• Community Ecology: Study of species interactions within a community.

• Diversity-Stability Hypothesis: Greater species diversity increases ecosystem stability. (Shannon Index formula example.)

• Succession:

  • Primary: Starts from bare rock (e.g., lava flow).

  • Secondary: Recovery after disturbance (e.g., forest fire). (Succession stage diagrams.)

• Conservation Strategies:

  • Protecting endemic species.

  • Habitat restoration and bioremediation.

  • Captive breeding programs.

Biodiversity

• Levels:

  • Species Diversity: Variety of species.

  • Genetic Diversity: Variation within species.

  • Ecosystem Diversity: Variety of habitats.

• Major Threats:

  • Habitat loss, climate change, overharvesting, invasive species.

• Small Population Challenges:

  • Inbreeding and genetic drift reduce diversity.

• Importance: Biodiversity boosts resilience, stability, and ecosystem services.

Terrestrial & Aquatic Biomes

• Terrestrial Biomes: Defined by temperature, precipitation, and vegetation. (Biome map recommended.)

• Aquatic Biomes:

  • Influenced by light, temperature, water density, and movement.

  • Marine Zones:

    • Intertidal: Shallow, affected by tides.

    • Neritic: Over continental shelf.

    • Pelagic: Open ocean.

    • Benthic: Seafloor.

    • Abyssal: Deep ocean. (Layered ocean diagram.)

Energy Flow & Biogeochemical Cycles

• Ecosystem Roles:

  • Producers → Make energy (plants).

  • Consumers → Eat other organisms.

  • Decomposers → Break down organic matter.

• Energy Transfer:

  • Trophic Levels: Only ~10% energy transfers between levels. (Pyramid diagram.)

• Key Cycles:

  • Water: Evaporation, condensation, precipitation.

  • Carbon: Photosynthesis, respiration, fossil fuels.

  • Nitrogen: Fixation, nitrification, denitrification.

  • Phosphorus: Rock weathering, uptake by plants.

  • Sulfur: Emitted by volcanoes, enters food web. (Diagrams for each cycle.)

Behavioral Ecology

• Animal Communication:

  • Chemical (pheromones), auditory (calls), visual (displays), tactile (touch).

• Social Behaviors:

  • Altruism: Helping others at personal cost.

  • Kin Selection: Helping relatives to pass on shared genes.

  • Reciprocal Altruism: Helping non-relatives with expected return.

• Mating Systems:

  • Monogamy: One mate.

  • Polygamy: Multiple mates (polygyny = many females, polyandry = many males).

  • Promiscuity: No specific pairing.

• Learning vs. Instinct:

  • Innate: Fixed action patterns, migration.

  • Learned:

    • Imprinting: Early life learning.

    • Conditioning: Associating behaviors with outcomes.

    • Cognitive Learning: Problem-solving.

Let me know if you want further adjustments or additional diagrams for any section!