Human Populations

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Human Populations

• Chapter 9

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• Demography
• the study of populations
• births,
• deaths,
• income,
• economics,
• incidence of disease,
• social structure,
• 7 Billion NatGeo
• http//www.youtube.com/watch?vsc4HxPxNrZ0listPL
  3072BF316D74A1DFindex2 3 min

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Demographers group countries as....

• DEVELOPED
• high average incomes
• slow population growth
• industrial economies
• good social systems
• good health care

• DEVELOPING
• low average incomes
• fast population growth
• agricultural economies
• poor social systems
• poor health care

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The Human Population.

• grew slowly for 1000s of years
• 1800s population reached 1 billion
• 1800s to today - rapid (EXPONENTIAL) growth
• today population over 7 billion

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For most of our human existence our ancestors
led precarious lives as hunter- gatherers (some
people still live like this) this kept our
population under 1 billion
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• The Industrial Revolution (1760s) brought about
  better living conditions and advancements in
  medicine, education, sanitation,..our population
  has grown to over 7 billion

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10,000 BC - about 1 million of us 1800s AD -
about 1 billion of us
1800s AD
10,000 BC
Graph Source www.census.gov www.wikipedia.org
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TODAY, we are off the chartwith a population
of OVER 7 billion
Exponential Growth J curve
In just 213 years (1800s to 2013) our
population has grown from 1 billion to over 7
billion)
Graph Source www.census.gov www.wikipedia.org
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World Population 7,071,548,6731835 UTC
(EST5) Mar 11, 2013

TODAYthe U.S. Census Bureau
estimates the World population at
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Whats your number?

• World Population Counter
• hyperlink
• http//populationaction.org/Articles/Whats_Your_Nu
  mber/Summary.php

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• World population reached
• 1 billion in 1800s
• 2 billion in 1927 (123 years later)
• 3 billion in 1960 (33 years)
• 4 billion in 1974 (13 years)
• 5 billion in 1987 (12 years)
• 6 billion in 1999 (12 years)
• 7 billion in 2011 (12 years)
• 8 billion in ?
• 9 billion in ?

Do you see a pattern?
TAKEN FROM http//bioweb.wku.edu/courses/Bi
ol115/wyatt/Population/pop1.htm
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What About The Future

• The projected estimates for 2050 are.
• 10.7 billion (high)
• 8.9 billion (middle)
• 7.3 billion (low)
• the world is adding about 78 MILLION more people
  every year

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Remember Carrying Capacity?

• What is the Earths carrying capacity?
• estimates - 10 -15 billion
• Why do these estimates vary?
• difficult to determine
• scientists use different methods to get estimates

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Our impact is increasing.
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Human Impact on The Environmentyear 1700, 2002,
(projected) 2032
Source Hugo Ahlenius. 2003. UNEP/GRID-Arendal.
Global Environmental Outlook 3, 2002.
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Forecasting/Projecting Population Size

• Demographers make predictions
• about populations using
• Age Structure
• Survivorship
• Fertility Rates
• Migration

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Age Structure

• distribution of ages in a population at a certain
  time
• can be graphed using a population pyramid (seen
  below)

Sweden and US have slow growth while Mexico
has rapid growth
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Survivorship

• percentage of individuals likely to survive to a
  given age

Centre County, Pennsylvania What was
survivorship in 1819? 1859? 1879?
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Survivorship Curve

• Type I most individuals live to an old age
  developed nations
• Type II similar death rates at all ages
• Type III most individuals die at early age
  many developing nations

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Fertility Rate

• Fertility Rate of babies born each year
• per 1,000 women
• Total Fertility Rate average number of children
  a woman gives birth to during her lifetime
• Total Fertility Rate varies from
• 1 - Japan and Italy - developed nations
• 7 - Niger and Mali - developing nations
• 2.1 - United States developed nation

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Total Fertility Rate

• Developed countries average 1.6 children per
  woman
• Developing countries average 3.1 children per
  woman
• Why is this number higher in developing
  countries?
• REPLACEMENT RATE - the rate at which
  a population neither grows nor shrinks
• 2.1 is generally regarded as the
  
• replacement rate in the developed world

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Do you notice any trends?
PalestinianTerritories Fertility Rate
1975-1980 7.39
1980-1985 7.00
1985-1990 6.43
1990-1995 6.46
1995-2000 5.99
2000-2005 5.57
Africa Fertility Rate
1975-1980 6.60
1980-1985 6.45
1985-1990 6.11
1990-1995 5.67
1995-2000 5.26
2000-2005 4.97
U.K. Total fertility rate
1975-1980 1.72
1980-1985 1.80
1985-1990 1.81
1990-1995 1.78
1995-2000 1.70
2000-2005 1.66
TOTAL
TOTAL
http//video.foxnews.com/v/2266634659001/declining
-fertility-rate-the-biggest-threat-to-america/ -
5 min
http//video.cnbc.com/gallery/?video3000137717
2 min
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Total Fertility Rate of babies per woman
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Migration

• MIGRATION movement of individuals between areas
• Immigration - movement into an area (or
  population)
• Emigration movement out of an area (or
  population)

Map shows first migratory routes taken by humans,
based on surveys of different types of the male Y
chromosome. "Adam" represents the common ancestor
from which all Y chromosomes descended. Research
based on DNA testing of 10,000 people from
indigenous populations around the world. Source
The Genographic Project
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Other Factors Affecting Population Growth

• Declining Death Rates
• Life Expectancy
• Infant Mortality

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Declining Death Rates.

• have allowed human population to increase
• more people have access to.
• adequate food
• clean water
• sewage disposal
• vaccines/immunizations and antibiotics

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Life Expectancy

• - is increasing throughout the world
• - average of years individuals of a population
  are likely to live

• Because of
• antibiotics
• immunization/vaccines
• improved standards of living
• adequate food
• clean water
• better sanitation

Life Expectancy Worldwide 67 years Developed
Countries 80 years
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Life Expectancy
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• Life Expectancy is most affected by
• Infant Mortality (rate) death rate of infants
  less than a year old (per 1000 live births)
• Infant Mortality varies
• as low as 3 - Singapore Iceland
• as much as 150 - Sierra Leone Afghanistan
• just over 6 United States
• High infant mortality tends to result in higher
  fertility rates as families seek insurance for
  the loss of children.

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Infant Mortality

• Infant Mortality (death) is DECLINING in most
  countries
• Infant Mortality is MOST AFFECTED
• by the parents access to.
• education,
• adequate food,
• fuel,
• clean water
• Expensive medical care is not as important

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Infant Mortality
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Demographic Transition

• model that describes how economic and social
  changes affect population growth

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Women and Fertility

• Decline in birth rates due to
• Increased education
• Economic independence for women

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Influences on Birth Rates

• Family planning programs
• Contraceptive technology
• Role of mass media

Government Billboard, Indonesia
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Rapid Population Growth ...

• 1. BRINGS ENVIRONMENTAL PROBLEMS
• 2. USES RESOURCES AT AN INCREASED RATE
• 3. CAN OVERWHELM INFRASTRUCTURE

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Environmental Problems
I P x A x T Impact Population x Affluence x
Technology

• Population-influenced environmental problems.
• Global Warming
• Habitat Loss / Endangered Species
• Resource Depletion
• Food Shortages? Not globally, but regionally.
• .

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Use of Resources at an Increased Rate(Resource
Consumption)
vegetation, water, land - most affected
resources In chapter 1 we talked about the 2
root causes of environmental problems. What
are they?
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Shortage of Fuel Wood

• Fuel Wood firewood, charcoal, chips, sheets,
  pellets, sawdust
• often it is the most available form of fuel for
  cooking heating

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Unsafe Water

• Local water supply may be
• used for drinking, washing
• and sewage disposal

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Barren Land

• loss of Arable Land (land used to grow crops)

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Much of the Worlds Population is undergoing
URBANIZATION

• URBANIZATION movement of people from rural
  areas to cities
• URBAN cities and towns
• SUBURBAN residential area outside an urban area
• RURAL outside cities and towns country

What are some problems associated with
urbanization?
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Infrastructure

• INFRASTRUCTURE basic facilities and services
  that
• 
  support a community
• public water, sewer, power plants, roads,
  schools, hospitals,

Inadequate Housing
Overcrowded Schools
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What might limit the human population?

• Lack of resources food, water, shelter
• Emerging Diseases Ebola, Hanta Virus, Lassa
  Fever, SARS,.

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Population Growth is Slowing

• Challenges to
• Population Control
• manufacture/distribution expense
• religion
• low female status
• fastest way to reduce fertility rate is to
  educate women
• preference for male children
• female Infanticide

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Human Population Forecasts/Projections
How many people will the planet eventually
support? it is thought that world
population will level off somewhere
between 9 and
11 billion people
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Overpopulation

• When consumption of natural resources by people
  outstrips the ability of a natural region to
  replace those natural resources.