Unit 3 Review

  • Focus of Unit 3: populations from human and natural ecosystem perspectives.

  • Natural Population Dynamics:

    • Differentiate between generalist (e.g., raccoons) and specialist (e.g., pandas) species.

    • Generalist species are more adaptable to disturbances; specialist species thrive in stable environments.

  • Reproductive Strategies:

    • R-strategists: many offspring, little care, high growth rate.

    • K-strategists: fewer offspring, significant care, longer maturity.

    • R-strategists can become invasive; K-strategists may struggle against invasive species.

  • Survivorship and Carrying Capacity:

    • Survivorship types: Type 1 (high care, K-selected), Type 2 (consistent mortality), Type 3 (minimal care, R-selected).

    • Carrying capacity: max population supported by resources, can lead to overshoots and diebacks.

  • Human Population Dynamics:

    • Age structure diagrams show population growth rates.

    • Larger pre-reproductive cohort indicates higher birth rates (developing countries).

    • Equilibrium in cohorts leads to slower growth.

  • Total Fertility Rate (TFR):

    • Average children per woman; influenced by age of childbirth, education, and culture.

  • Demographic Transition Theory:

    • Four stages: high birth/death rates (pre-industrial) to low birth/death rates (industrialized).

    • Population initially grows, then stabilizes or declines as societies develop.