Chapter 8: The Human Population Flashcards
Demograhy
collecting, compiling, and presenting info about human populations
Demographers
study population processes (migration, changes in fertility, mortality)
r-selected species (r-strategists)
have high reproductive potential (r), short-lived, low parental care
K-seleced species (K-strategists)
remain close to carrying capacity (K), long life spans, older age at first reproduction, parental care, fewer offspring
Why are humans critically different from other species?
- They show exponential growth (r-strategists)
2. They have high parental care (K-strategists)
What happened in the 20th century?
the human population tripled
What has led to improved well-being?
Technology
- What has risen, and
2. how much has infant mortality been reduced by?
- life expectancy
2. 2/3rds
What kind of curve does human population growth show?
J-shaped curve
Population
an interbreeding group of a species in the same area
Global population are…
interconnected
Only humans can regulate…
reproduction
How have the revolutions changed our lives?
- they changed the way humans interact with their environment
- brought humans from a number of isolated population to the global poplation of today
Paleolithic life (50,000 - 10,000 yrs ago)
- lived in small tribes
- hunter-gatherers
- moved constantly
- nomadic omnivors
Neolithic Revolution (12,000 years ago)
- people in the Middle East began to develop animal husbandry and agriculture (abundant food supply)
What did the Neolithic Revolution result in?
settlements and specialization of labor
- technology produced tools, trae, cities, food storage (trade and commerce were born)
Whad did the Neolithic Revolution reduce?
mortality and reliable food production equals population growth
What led to the Industrial Revolution?
the birth of modern science and technology in the 17th and 18th centuries
Industrial Revolution
- technology energized by fossil fuels
- coal, oil, and natural gas let people do much more work than by human or animal power
- the extra energy let people produce more food
Negatives of the Industrial Revolution
produced pollution and resource exploitation
What led to the Medical Revolution?
- diseases hit infants and children the hardest
- Epidemics killed adults
- humans had high reproductive rates and high mortality rates, resulting in low population growth
- scientists were able to tell that diseases were caused by infectious agents
The Medical Revolution (18th century)
- Decreases in child and infant mortality
2. High birth rates and low mortality rates resulted in exponential population growth
What were the decreases in child and infant mortality due to?
- vaccinations
- cities and towns treating sewage and drinking water
- penicillin cured pneumonia and blood poisoning
- nutritional improvements
Green Revolution (industrialized agriculture)
Crops, fertilizer, irrigation, and pesticides are all part of industrialized agriculture
What caused the Green Revolution?
concerns over producing food for the larger populations
- pesticides, irrigation, and fertilizer increased yields
- countries could feed growing populations
Costs of the Green Revolution
- erosion, soil and water pollution, loss of native plants
- soil and water being used faster than they can be replaced
- pesticide resistance
Pesticide Resistance
target organisms are no longer affected by pesticides
Population growth is pressurig for more…
production
The newest revolution
The Environmental Revolution
What will the Environmental Revolution come from?
- efficient technologies, urban and regional planning
- policy and industrial changes
- personal decisions to reduce impact on planet
Which revolution has the greatest impact on the future quality of human life?
The Environmental Revolution
Order of revolutions
- Neolithic Revolution
- Industrial Revolution
- Medical Revolution
- Green Revolution
- Environmental Revolution
What have humans done through all five revolutions?
increased their carrying capacity
What are some limiting factors of the 20th century?
- pollution
- limited agricultural space
- depleted fisheries
- trade-offs beween ecosystems we need for their services vs. land and water needed for human activities
What is the best estimate for human carrying capacity?
7.7 billion
When are we expected to exceed this carrying capacity?
2024
How many people will their be by 2085?
10 billion people
Developed countries
high-income nations
Developing countries
middle- and low-income nations
What does Human Development Index measure?
general well-being
What is well-being/Human Development Index based on?
Life expectancey, education, per capita income
Human Poverty Index
literacy and iing standards directly measure poverty
Population growth in rich nations
Rich nations = 0.1% per year
Population growth in middle and low income nations
1.5% per year
Where is growth rate lowest?
uper income nations
What kind of nations have larger populations and higher birth rates?
Developing nations
Total fertility rate (TFR)
average number of kids each woman has over her lifetime
Replacement-level fertility
fertility rate that replaces the parent’s population
Fertility rates have dropped…
globally
Where have fertility rates dropped the most?
developed countries
What is the I=PAT formula?
Environmental Impact = Population x Affluence and Consumption x Level of Technology of the Society
What does the I=PAT formula describe?
human factors that contribute to environmental deterioration and resource depletion
How can developed nations severely impact the environment?
High A and T, but a small P
Environmental impacts are not always experienced at the same place where…
the resources are consumed
Some high-density places have healthy, long lived people, but…
these places can be so crowded because they use resources over a much wider area (their impact is far-reaching)
Ecological (environmental) footprint
estimate of the amount of land and ocean required to provide resources and absorb wastes
What can help estimate an environmental footprint?
IPAT formula
The GINI Index
measures inequality in nations
What county has the lowest inequality?
Sweden (23)
What country has the highest inequality?
South Africa (65)
Where does the U.S. lie in the measurement of inequality?
(45), the top 1% own 47% of the wealth
What can the technology part of IPAT be lowered by?
Stewardship (I=PAT/S)
What may offset the negative impact of a consumer lifestyle?
- attention to wildlife conservation
- pollution control
- energy conservation and efficiency
- recycling
What three things must happen to transition to a sustainable future?
- populations must stabilize (birth control)
- consumption must decrease
- stewardly action must increase
Five options for nations with high population growth
- Intensifying cultivation
- Opening up new lands
- Illicit activities
- Migration between countries
- Migration to cities
Intensifying cultivation
highly productive crop varieties produce more food
Opening up new lands
most good land is already in producion
- conversion of forests to ag. space
- Ex. slash and burn in the rainforest to create ag. and grazing land
Illicit activities
desperate people break the law
- joblessness results in growing drug-related crops and poaching wildlife
Migration between countries
to improve well-being
- 35% of immigrants in the U.S. have entered illegally
- escape civil wars or ethnic persecution
Migration to cities
for jobs and a better life
- by 2050, 70% of pop. will live in cities
- pop. growth and migration to cities are outpacing economic growth
- rapic growing cities can’t provide basic services
What problems do rich nations face?
- they develop the most pollution
- the world’s richest 20% are responsible for 76% of all consumption and 80% of trade
- transfer waste to distant locations and don’t see the negative impacts
What does wealth allow for?
Conservation, management, better agriculture, pollution control
What caused the reduced growth rates and fewer people added?
Lower fertility rates
What was the TFR in the 1960’s and what is it now?
Then: 5.0
Now: 2.6
What affects population growth?
the age at which a woman first reproduces (earlier reproduction results in higher growth)
When will populaion level off?
the 22nd century
What must people do to reach “only” 93 billion?
purposefully reduce their fertility at a rate we are not yet seeing
Population profile
shows the number of people (males and females) at each age for a population
Age structure
the number of people in each age group at a given date
Projections
using clear assumptions about fertility, mortality, and migration
What does a graying population have
a high proportion of elderly (possible to have a net population decline)
What are fertility rates in graying populations?
less than 2
What will European countries have to do to help their culture survive?
- Encourage more children
- offer child allowances, tax credits, large-family discounts - Be open to immigration
Highly developed countries ith lower FR’s are facing the problems of…
a graying nation
What would an ideal population age structure have?
- An equal number of people in each 15-year age group
2. a life expectancy of 75 years
Declining fertility rates in developing countries are still well above what?
Replacement level fertility
What is the average TFR in developing countries?
3.2
With a TFR of 6.3, Burkina Faso’s populaton will increase from ______ to _____
15.3 to 25.4 million
What percentage of the population is younger than 15 in many developing nations?
40-50%
Population momentum
the effect of current age structures on future populations
When will a stable population be obtained?
When the population has been at replacement levl fertility for decades
Demographic transition
a shift in birth and death rates from the primitive to the modern societies
Modern societies
lower birth rates, lower death rates, and are industrialized
Primitive:
high birth rates being offest by high death rates
Crude birth rate (CBR)
the number of births per thousand people per year
Crude death rate (CDR)
number of deaths per thousand people per year
CBR - CDR =
natural increase (decrease) per 1,000 per year
% increase (decrease) =
natural increase (decrease)/10
Zero growth
CBR and CDR are equal and no migraition
Epidemiologic transition
the pattern of change in mortality factors (disease, etc.)
Fertility transition
crude birthrates have declined in developed countries
- didn’t happen at same time as eidemiologic transition
- was delayed until decades after the eidemiologic transition
When CBR and CDR are out of phase…
rapid population growth occurs
Pases of the demographic trasition
Phase I
Phase II
Phase III
Phase IV
Phase I
primitive stability (high CBR is offset by high CDR)
Phase II
Epidemiologic transition due to medical revolution
- declining CDR
- High CBR results in rapid population growth
Phase III
Fertility rates declining, population growth is still significant
Phase IV
Modern stability is reached, CDR and CBR are both low
What phase are developed countries in?
Phase IV
What phases are developing countries in?
Phase II and III
