Presentation on theme: "Class Notes 7: Human Population "Go Forth And Multiply!" That's what the human population has successfully been doing for thousands and thousands of years,"— Presentation transcript:
Class Notes 7: Human Population "Go Forth And Multiply!" That's what the human population has successfully been doing for thousands and thousands of years, expanding, exploring, migrating, conquering, utilizing, evolving, civilizing, industrializing, and now, destroying the very land upon which we live.
I. World Population (A) In the U.S., a census is taken every 10 yrs. 1.Includes how many people, economic condition, and where they live. (B) Demography the study of human population size, density and distribution, movement, and its birth and death rate. (C) What factors affect growth of human population? Eradicated diseases Increase food supply Infant mortality rate decrease Clean Water * people live longer->reproduce more=population grows
II. Calculating Growth Rate (A)There are a number of factors that determine population growth rate. 1.Birthrate is the number of live births per 1000 population in a given year. 2.Death rate is the number of deaths per 1000 population in a given year. (birthrate + immigration) – (death rate + emigration) = Population Growth Rate (PGR)
III. Doubling Time (A)Doubling Time is the time needed for a population to double in size. 1.Depends on the current population and growth rate a.Fast growth rate = fast doubling time b.Slow or negative growth rate = slow doubling time