Population Dynamics, Carrying Capacity, and Conservation Biology Chapter 9 “In looking at nature…never forget that every single organic being around us may be said to be striving to increase its numbers.” Charles Darwin, 1859

Key Concepts Factors affecting population size Species reproductive patterns Species survivorship patterns Conservation biology and human impacts on ecosystems

Population Dynamics and Carrying Capacity Population dynamics Zero population growth (ZPG) Biotic potential (intrinsic rate of increase [r]) Environmental resistance Carrying capacity Minimum viable population (MVP)

Population Dispersion

Factors Affecting Population Size

Exponential and Logistic Growth Fig. 9-4 p. 192 Fig. 9-6 p. 193 Fig. 9-5 p. 193

Population Density Effects Density-independent controls Density-dependent controls

Natural Population Curves

The Role of Predation in Controlling Population Size Predator-prey cycles Bottom-up control Top-down control

Reproductive Patterns and Survival Asexual reproduction Sexual reproduction r-selected species K-selected species Fig p. 196

Question Why are pest species likely to be extreme r- selected species? Why are many endangered species likely to be extreme K-selected species?

Survivorship Curves Fig p. 198

Conservation Biology: Sustaining Wildlife Populations Investigating human impacts on biodiversity Ideas for maintaining biodiversity Endangered species management Wildlife reserves and ecological restoration Ecological economics Environmental ethics Wildlife management

Human Impacts on Ecosystems Habitat degradation and fragmentation Ecosystem simplification Genetic resistance Predator elimination Introduction of non-native species Over harvesting renewable resources Interference with ecological systems

Learning From Nature Interdependence Diversity Resilience Adaptability Unpredictability Limits

Assignment In groups of four…choose one wild plant species and one animal species and analyze the factors that are likely to limit the populations of each species. Make an informational poster about the species (you will have two – one plant and one animal) on half of a piece of paper and then make an informational poster about the limitations on the other half.