Presentation on theme: "Chapter 8 Understanding Population Change. Principles of Population Ecology Populations exhibit characteristics unique to the individual. Populations."— Presentation transcript:
Chapter 8 Understanding Population Change
Principles of Population Ecology Populations exhibit characteristics unique to the individual. Populations are central to many environmental problems. Population ecology- deals with the number of individuals of a particular species that are found in an area and how and why those numbers increase or decrease over time, and how they respond to their environment.
Demographic Stages Populations undergo four stages as a society becomes industralized: Preindusrial, Transitional, Industrial, and Postindustrial
Factors that Affect Population Size Density-Dependent Factors Tend to slow population growth by causing an increase in death rate and/or decrease in birth rate Keep population at carrying capacity Predation, disease, and competition Density-Independent Factors Random events that are not a result of population, but can have an effect on population size. Blizzards, Frosts, tornadoes, hurricanes, etc.