Human DeMOGRAPHICS

Human Demographics The study of human populations is referred to as demography. data collection statistical analyses theoretical models to interpret and predict human growth and distribution See page 705 Figure 1!  

Growth rates When the growth rate is 0.02 the percentage growth rate is 2%! birth rates have remained relatively constant, but death rates have dropped dramatically, causing a doubling time of approximately 43 years doubling time (td) can be approximated using td = 0.69 / r (where r is the growth rate) From 1996 to 2001 Canada’s population grew by 4.0%...at this rate how long will it take to double our population?

Key factors responsible for significant variation in population growth rates in different regions of the world differences in age structure

Age structures of populations exhibiting differing growth rates

Activity Try This page 709

Answers! A) Canada - 35-39 Nigeria - 10 and under Denmark – 30-39 B) Canada – few children...slow growth Nigeria – Lots of children ...rapid growth Denmark – 30-39 – balanced pop...slow growth

Answers! c) - All three have equal male/female ratios -Nigeria...lots of children...steady decrease in older pop -Canada & Denmark...balanced -Pop # differences -More older women than men

Answers! d) Governments need to plan to provide for social services before they are most needed!! For example...cutting the long form census in Canada! www.cbc.ca/canada/story/2010/07/07/liberals- census.html

The Demographic Transition Model birth and death rates influence human population growth factors that increase or decrease death rates in older individuals in their post-reproductive years have little effect on growth rates

the demographic transition model suggests that as societies shift from agricultural production to industrialization, population size increases highly industrialized and economically secure countries population growth rate slowly decreases countries that are still developing industrial economies continue to experience rapid population growth

Zero population growth a condition in which the number of individuals added to a population (birth and immigration) equals the number of individuals removed from a population (deaths and emigration)

Population Vs Food Sources As early at 1798, Thomas Malthus predicted that exponential human population growth would surpass the arithmetic growth of food resources Humanity is living in unsustainable ways that stretch the ecological limits of the planet’s ability to support human life

Effects on Life Support Systems “Try This” activity on P 712

Door #1 High (10.9 billion) -Improved childcare -Failure of family planning programs in developing areas (Africa, Asia, South America) -Improvement of food technologies -Better infrastructure -Increased reproduction in industrialized nations

Door #2 Medium (9.3 billion) -Slight improvement in childcare -Some success with family planning programs in developing areas (Africa, Asia, South America) -Food technologies and infrastructure stay similar to how they are now

Door #3 Low (7.9 billion) -No improvement childcare -Good success of family planning programs in developing areas (Africa, Asia, South America) -Medical epidemic wiping out people of reproductive age.

Homework P 713 #1-5