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_________ _____________ DYNAMICS
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Is the World Overpopulated?
Much of the world’s population ________ occurs in developing countries like ______ and _______. The world’s population is projected to increase from ___ billion to ____ billion by _______. Fig. 6-1, p. 125
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______ Most Populous Countries, 2010 and 2050
Figure 6.4: This chart shows the populations of the world’s five most populous countries in 2010 and 2050 (projected). In 2010, more than one of every three persons on the earth lived in China (with 19% of the world’s population) or India (with 17%). (Data from United Nations Population Division) Fig. 6-4, p. 127
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Is the World Overpopulated?
Some argue that the planet has _____ many people. Some feel that the world can support _______ of more people due to _____________ advances. Constant _______ over the need to reduce population growth. Must consider _______, __________, and ________ freedom. Do not know how long we can continue increasing the earth’s carrying capacity for humans. Likely to be between ________ billion people on earth by 2050. ______% of growth in developing countries living in acute ________.
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_______ on Population Growth
No population can increase its size ___________. As the human population ______, so does the global total human _________ footprint _________ ________ __________ Total ________ of people who could live in ___________ freedom and comfort __________, without _________ the ability of the earth to sustain ______ generations
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Population Growth Cycle
______ ________– a populations capacity for growth As a population levels off, it fluctuates slightly _____ and ______ the carrying capacity. Biotic Potential ex. Housefly can lay 120 eggs in each generation. If nothing hurt the eggs or the flies, in 7 generations there would be 6,182,442,727,320 flies.
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Humans Are Not Exempt from Nature’s Population Controls
________ Potato crop in 1845 ________ _________ Fourteenth century ______ Global epidemic
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Exceeding Carrying Capacity: Move, Switch Habits, or Decline in Size
Over time species may _______ their carrying capacity by developing __________. Some species maintain their carrying capacity by _________ to other areas. So far, technological, social, and other cultural changes have _________ the earth’s carrying capacity for humans.
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Features of Populations
Populations are dynamic and exhibit attributes that are not shown by the individuals themselves. These attributes can be measured or calculated and include: _____________: the total number of organisms in the population. ____________: the number of organisms per unit area. ________________: the location of individuals within a specific area.
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Features of Populations
Population composition provides information relevant to the ________ of the population, i.e. whether the population is _________ or __________. Information on population composition (or structure) includes: __________: the number of organisms of each sex. __________ (fertility): the reproductive capacity of the females. ___________: the number of organisms of different ages.
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Population ___________
The study of _________ in the size and composition of populations, and the ________ influencing these changes, is population dynamics. Key factors for study include: Population _______ rate: the change in the total population size per unit time. __________:(birth rate): the number of individuals born per unit time. __________ :(death rate): the number of individuals dying per unit time. __________:the number moving into or out of the population. Population size is influenced by births… …and deaths
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Migrating species may group together to form large mobile populations
____________ Migration is the _________ of organisms into (___________) and _____ of (___________) a population. It affects population attributes such as age and sex structure, as well as the dynamics of a population. Populations _______ individuals through deaths and emigration. Populations _______ individuals through births and immigration. _____ Migration = Immigration – Emigration Net Migration _____ = Number of Immigrates/ Number of people in population. Wildebeest - land based migration Canada geese - aerial migration Migrating species may group together to form large mobile populations
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Population ___________
Population Density - _______ of individuals per unit ______ or ________. Can affect how rapidly a population can grow or decline. Ex. _______ factors like disease. Some population control factors are not affected by population density. Ex. ________ factors like weather. At _____ densities, individuals are spaced well apart. Exs: territorial, solitary mammalian species such as tigers. At ______densities, individuals are crowded together. Examples: colonial animals, such as rabbits, corals, and termites. Low density populations ( population ) = Population Density area High density populations
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Population Distribution
A _______ measure of population density tells us nothing about the ________ distribution of individuals in the habitat. The population distribution _________ the location of individuals within an area. Distribution patterns are determined by the habitat ___________ (distribution of resources) and _________ of the organisms themselves, such as territoriality in animals or autotoxicity in plants. Individuals in a population may be distributed __________, ___________, or in _________. Clumped distribution in termites More uniform distribution in cacti
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__________ Distribution
A population’s distribution is considered _________ if the position of each individual is ____________ of the others. Random distributions are ____ common; they can occur only where: The environment is ________ and resources are equally available throughout the year. There are ____ interactions between individuals or interactions produce no patterns of avoidance or attraction. Random distributions are seen in some ___________ populations, e.g. spiders and clams, and some trees. Spider populations appear to show a random distribution
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__________ Distribution
________ or regular distribution patterns occur where individuals are more _______ spaced than would occur by chance. Regular patterns of distribution result from ____________ competition amongst members of a population: Territoriality in a relatively _____________ environment. Competition for root and crown space in forest trees or moisture in desert and savanna plants. ____________: chemical inhibition of plant seedlings of the same species. Saguaro cacti compete for moisture and show a uniform distribution
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__________ Distribution
_________ distributions are the _______ common in nature; individuals are clustered together in groups. Population clusters may occur around a ________ such as food or shelter. Clumped distributions result from the responses of plants and animals to: _________ differences Daily and seasonal changes in ________ and environment ____________ patterns ________ behavior Sociality leads to clumped distribution
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Density ___________ Factors
Density dependent factors exert a ________ effect on population growth at _______ population densities. At high densities, individuals: Compete ______ for resources. Are more _______ located by predators and parasites. Are more ___________ to infection and disease. Density dependent factors are _________ factors such as food supply, disease, parasite infestation, competition, and predation. Competition increases in crowded populations The intrinsic rate of increase (r) is the rate at which a population would grow if it had unlimited resources. Carrying capacity (K): the maximum population of a given species that a particular habitat can sustain indefinitely without degrading the habitat. Parasites can spread rapidly through dense populations
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Density ___________ Factors
The effect of density independent factors on a population’s growth is not dependent on that population’s density: ________ (or abiotic) factors temperature precipitation humidity acidity salinity etc. ____________events floods and tsunamis fire drought earthquake and eruption Factors that are not a part of the growing population. These factors are beyond the control of the organism and are usually result of the environment.
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(Births – Deaths) + (Immigration – Emigration)
Population ________ Population growth _________ on the number of individuals added to the population from ________ and ________, minus the number _____ through ________ and _________. This can be expressed as a formula: _______ birth and ______ death rates used which is #live births per ______ per year and # of deaths per _______ per year Population growth = (Births – Deaths) + (Immigration – Emigration) (B) (D) (I) (E)
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Growth rate ________population growth rate
(______ rate-_______ rate)/10 _________ population growth rate (______ rate-______ rate) + (_________ – ____________) / 10 If a population of 10,000 experiences 100 births, 40 deaths, 10 immigrants and 30 emigrants in a year, what is the national population growth rate?
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________ Rate of _______ Population Change (%)=
Birth rate – Death rate ______ people x ____
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Rates of Population Change
Ecologists usually measure the rate of population change. These rates are i_________ by ____________ factors and by the __________ of the organisms themselves. Rates are expressed as: _________per unit time, e.g live births per year _____ _______ ______(number per head of population), e.g. 122 live births per individuals (12.2%) Many invertebrate populations increase rapidly in the right conditions Large mammalian carnivores have a lower innate capacity for increase
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Colonizing Population Population numbers (N)
___________ Growth Populations becoming established in a new area for the first time are often termed ________ populations. They may undergo a rapid ___________ (logarithmic) increase in numbers to produce a ___-shaped growth curve when plotted over time. ___________ growth- growth that increases at a constant rate per unit of time. Ex. - the growth sequence 2, 4, 8, 16, 32, 64 and so on In __________ populations, population growth rarely continues to increase at an exponential rate. _________ in the environment, such as available food or space, act to _______ population growth. Colonizing Population Here the number being added to the population per unit time is large. Exponential (J) curve Exponential growth is sustained only when there are no constraints from the environment. Population numbers (N) For example the common housefly can lay 120 eggs in each generation. If nothing hurt the eggs or the flies, in 7 generations there would be 6,182,442,727,320 flies. Here, the number being added to the population per unit time is small. Lag phase Time
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_________ Growth Model
As a population _____ and it encounters _____________ resistance, its increase will slow, and it will stabilize at a level that can supported by the environment. This type of ___________ growth (___) produces the logistic growth curve when plotted over time. Established Population The population encounters resistance to exponential growth as it begins to fill up the environment. This is called environmental resistance. Carrying capacity (K) The maximum population density that can be supported by the environment on a long term basis. Environmental resistance increases as the population overshoots K. Logistic (S) curve As the population grows, the rate of population increase slows, reaching an equilibrium level around the carrying capacity. Population numbers (N) Populations grow rapidly with ample resources, but as resources become limited, its growth rate slows and levels off. As a population levels off, it often fluctuates slightly above and below the carrying capacity. The intrinsic rate of increase (r) is the rate at which a population would grow if it had unlimited resources. Carrying capacity (K): the maximum population of a given species that a particular habitat can sustain indefinitely without degrading the habitat. Environmental resistance decreases as the population falls below K. The population tends to fluctuate around an 'equilibrium level'. The fluctuations are caused by variations in the birth rate and death rate as a result of the population density exceeding of falling below carrying capacity. In the early phase, growth is exponential (or nearly so) Lag phase Time
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Exponential and Logistic Population Growth: J-Curves and S-Curves
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Population overshoots carrying capacity Carrying capacity
2.0 Population overshoots carrying capacity Carrying capacity 1.5 Population recovers and stabilizes Population runs out of resources and crashes Number of sheep (millions) 1.0 Exponential growth .5 Figure 5.15: This graph tracks the logistic growth of a sheep population on the island of Tasmania between 1800 and After sheep were introduced in 1800, their population grew exponentially, thanks to an ample food supply and few predators. By 1855, they had overshot the land’s carrying capacity. Their numbers then stabilized and fluctuated around a carrying capacity of about 1.6 million sheep. Populations grow rapidly with ample resources, but as resources become limited, its growth rate slows and levels off. 1800 1825 1850 1875 1900 1925 Year Fig. 5-15, p. 115
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______ Tables Numerical ______ collected during a population study can be presented as a table of figures called a _____ table. Life tables provide a summary of _______ for a population. The basic data are the number of individuals surviving to each age interval. This gives the ages at which most mortality occurs in a population. Life table for a population of the barnacle Balanus Age (yr) No. alive at the start of the age interval Proportion of original no. surviving at the start of the age interval No. dying during the age interval Mortality (d) 142 1.000 80 0.563 1 62 0.437 28 0.452 2 34 0.239 14 0.412 3 20 0.141 5 0.250 4 15 0.106 0.267 11 0.078 0.454 6 0.042 0.667 7 0.014 0.000 8 9 0.0 –
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Number of survivors (log scale)
_____________ Curves The _____structure of a population can represented with a __________ curve. Survivorship curves use a semi-log plot of the number of individuals surviving per 1000 in the population, against age. Because they are standardized (as number of survivors per 1000), species with different life expectancies can be easily compared. The _______ of the curve reflects where __________ mortality occurs: Type I: late loss large mammals Type II: constant loss small mammals, songbirds Number of survivors (log scale) Type III: early loss oysters, barnacles Relative age
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Type ____ Survivorship Curves
Species with Type I or _____ loss survivorship curves show the heaviest mortality _____ in life. Mortality is very low in the juvenile years and throughout most of adult life. Late loss curves are typical of species that produce _____ young and care for them until they reach _____________ age. Such species are sometimes called ____- selected species and include elephants, humans, and other large mammals. Mortality is very low in early life Mortality increases rapidly in old age
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Type ____ Survivorship Curves
Species with Type II or ________ loss survivorship curves show a relatively ________ mortality at all life stages. Constant loss curves are typical of species with ____________reproductive strategies. Populations face loss from __________ and _________throughout life. Examples include some many types of songbirds, some annual plants, some lizards, and many small mammals. Constant mortality. No one age class is any more susceptible than any other.
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Type _____ Survivorship Curves
Species with Type III or ______ loss survivorship curves show the highest mortality in _______ life stages, with low mortality for those few individuals reaching a certain age and size. Early loss curves are typical of species that produce _______ number of offspring and ______ parental care. Such species are ___- selected species (____________), and include most annual plants, most bony fish (although not mouth brooders), and most marine invertebrates. Population losses are high in early life stages Mortality is low for the few individuals surviving to old age
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‘____’ and ‘____’ Selection
Two parameters govern the logistic growth of populations. The __________ rate of natural increase or biotic potential. This is the ___________ reproductive potential of an organism, symbolized by the letter r. The _________ density or carrying capacity of the environment, represented by the letter, K. We can characterize species by the relative importance of __ and __ in their life cycles. K-selected species These species exist near asymptotic density (K) for most of the time. Competition and effective use of resources are important. Population numbers (N) r-selected species These species rarely reach carrying capacity (K). Their populations are in nearly exponential growth phases for much of the year. Early growth, rapid development, and fast population growth are important. Time
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___-Selected Species Correlates of K-selected species Species that are K- selected exist under ________ competition and are pushed to use available resources more ___________. These species have _______ offspring and longer lives. They put their energy into _________ their young to reproductive age. ____-selected species include most large mammals, birds of prey, and large, long-lived plants. Climate Fairly constant and/or predictable Mortality Density-dependent Survivorship Usually types I and II (late or constant loss) Population size Fairly constant in time. Near equilibrium with the environment. Competition Usually keen. Specialist niche. Selection favors Slower development, larger body size, greater competitive ability, delayed reproduction, repeated reproductions Length of life Longer (> one year) Leads to: Efficiency
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____-Selected Species
Species with a high intrinsic capacity for population increase are called r- selected or __________ species. These species show certain life history features and, to survive, must continually ________ new _______ to compensate for being displaced by more competitive species. ____________ include algae, bacteria, rodents, many insects, and most annual plants. Correlates of r-selected species Climate Variable and/or unpredictable Mortality Density-independent Survivorship Often type III (early loss) Population size Fluctuates wildly. Often below K. Competition Variable, often lax. Generalist niche. Selection favors Rapid development, high rm, early reproduction, small body size, single reproduction (annual) Length of life Short, usually less than one year Leads to: Productivity
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____________ Demography is the ______ of human populations, their characteristics and changes. Demographics will measure: Statistics about people, such as _______, ______, and where they _______ as well as total population _____. GO TO census.gov and obtain the current world population and the current US population.
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Science Focus: Projecting Population Change
Why range of billion for 2050? _____________ must: Measure _________ about people, such as birth, deaths, and where they live as well as total population size. Determine ________ of current estimates. Make assumptions about ________ trends. Deal with different ___________ and sets of ____________.
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Human Population Growth
The world population, now over ____ billion, is growing at the rate of about million per year. Projections put the world population at between ___ and ___ billion in 2050, with nearly all of this growth expected in the developing world. ___________ countries include: Africa, Asia, Latin America, the Caribbean, and regions of Melanesia, Micronesia, and Polynesia. The human population has grown rapidly because of the expansion of ___________ and _________ production and ______ death rates from _________ in hygiene and medicine. The debate over interactions among population growth, economic growth, politics, and moral beliefs is one of the most important and controversial issues in environmental science. Developing countries grew at ___% (15 times faster) Developed countries grew at ____%
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Growth Rate and percent change
_______ rate includes the birth rate, death rate, immigration and emigration. Usually calculated using the __________: _______ in pop = (B+I) – (D+E) ___ ________ = change in value/old value x 100% If a population of 10,000 experiences 100 births, 40 deaths, 10 immigrants and 30 emigrants in a year, what is the annual percentage growth rate? ( ) – ( ) = 40 40/10,000 x 100% = 0.4%
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_________ Time: Rule of ___
_________ time is the _____ it takes for the population to ________ the number of people in the current population. Calculated as __ / % growth rate ____/ growth rate = doubling time If a population of a country grows at a rate of 5% a year, the number of years required for the pop to double is what?
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Doubling Time: Rule of 70 Growth Rate (% per year)
Doubling Time in years 700 0.5 140 1 70 2 35 3 23 4 18 14 6 12 7 10
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______ Population Growth
Estimates of likely ______ growth of the world human population are highly uncertain and projections for 2050 range from a low of ____ billion to a high of _____ billion. Global Human Population Growth High fertility rate: 11.2 billion Medium fertility rate: 9.4 billion Low fertility rate: 7.7 billion North America Latin America & Caribbean Europe Asia & Oceania Africa Note: The latest ‘medium variant’ U.N. projection of 9.37 billion is nearly 500 million (4.7%) lower than the 9.83 billion projected in 1994.
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___________ Transitions
__________where countries become ___________ developed then their birth and death rates begin to decline. In the past this was referred to as “_____” and “______” world countries or “__________” and “___________”. Currently this process is described by the different stages according to population growth: _____________ stage shows little population growth due to high birth rate with high death rate. ____________stage is where industrialization begins, death rates drops and birth rates remain high. Rapid population growth occurs. __________ stage is birth rate dropping and approaching death rate. Population growth slowly declines. ___________ stage are birth rate and death rate become similar and population growth slows or declines. Post-industrial: 37 countries have reached this stage. (mainly in W. Europe) To most population experts, the challenge is to help the remaining 88% of the world to get to this stage.
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Demographic Transition
97% of growth in developing countries living in acute poverty usually occurs during the transitional stage. What is the optimum sustainable population of the earth based on the cultural carrying capacity? Generalized model of demographic transition shows that the total ________ of a society _________ as the society progresses through the demographic transition. Some _______ countries may have difficulty making the demographic transition.
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Demographic Transition
Post-industrial: 37 countries have reached this stage. (mainly in W. Europe) The challenge is to help the remaining 88% of the world to get to this stage. initially birth rate and death rate are both high, birth rate remains high, death rate declines (because of better health care, etc.), birth rate declines and approaches death rate (mention of postindustrial phase with explanation is acceptable).
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Size/age classes in fish
_____ __________ Age structure refers to the _________ of organisms of different _____. Populations can be broadly grouped into those individuals of: _____________ age ____________ age ______ ___________ age ________ of the age structure of populations can assist in their management because it can __________ where most population __________ occurs and whether or not _____________ individuals are being _________. Size/age classes in fish
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Human _____ Structure Human age structure varies from country to country. Number of people younger than age ___ is the major factor determining a country’s population ________. In __________ countries age structure tends to be in favor of younger individuals with a large proportion being _______ 15 years. In _________ nations, age structure is relatively _______ throughout the age groups. Age Structure in Human Populations Changes in distribution of a country’s age groups have long-lasting ___________ and _______ impacts.
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Determining Population Growth
The ______ at which a population grows or declines depends on its _____ structure. Age structure diagrams show the ________ of different age groups. These groups are further broken into cohorts: ____________ age (____) are persons who are not mature enough to reproduce ___________ age (_____)are those persons that are capable of reproduction. _______________ age (____) are those persons too old to reproduce.
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Age Structure Diagrams: Histograms
Populations with a large proportion of its people in the preproductive ages 1-14 have a large potential for rapid population growth. Those with a large proportion of people in reproductive age are experiencing rapid population growth.
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Age Structure Since age structure diagrams are broken down by age, demographers can obtain: ______ rate ________ rate ______ rate of an entire population. These diagrams are usually broken down by ________ and divided into ________. ____% of the people in developing countries were under 15 years old in 2012 versus only ____% in developed countries. Changes in the distribution of a country’s age groups have long-lasting economic and social impacts.
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Age Structure: United States
Today, baby boomers make up nearly half of all adult Americans and dominate the populations demand for goods and services. Because of ______ boom, the US has a bulge(yellow) in the pyramid with people in their ________. There are ______ women than men in the older group because of differences in ___________ between sexes.
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_______ Growth Diagram
A relatively large segment of the population of the country is currently in the prereproductive/reproductive years and will soon begin having children (giving the population momentum). _________ shaped histograms have a birth rate that ________ the death rate. Lower cohorts have more males and females. Population growth is ______ in countries that have a pyramid shape. Current modern examples include Africa, Asia, and Latin America
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____________ Growth Diagrams
Birth rate exceeds the death rate. Population is getting larger. Pyramid shaped histogram. In contrast, the prereproductive cohorts in county Y are about equal in size to the reproductive and postreproductive cohorts. When the histogram shape is “_____”-like, then stable or slow growth is represented. Birth rate is ________ equal to death rate. Sometimes called _______ growth. Current examples of slow growth: USA, Australia, & Canada Current examples of stable growth: Denmark, Austria, & Italy
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_________ Growth Diagrams
Birth rate exceeds the death rate. Population is getting larger. Pyramid shaped histogram. If there is __________ or _________ growth, then the birth rate with be _____ than the death rate. Pyramids with declining populations tend to show _______ numbers of ________ persons in their population. Current examples: Germany & Japan
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______ decline manageable
Some Problems with Rapid Population Decline Can threaten economic growth ______ decline manageable ______ decline causes severe ________ and _______ problems. How do we pay for services for elderly? Labor shortages Less government revenues with fewer workers Less entrepreneurship and new business formation Less likelihood for new technology development Figure 6.15: Rapid population decline can cause several problems. Question: Which three of these problems do you think are the most important? Increasing public deficits to fund higher pension and health-care costs Pensions may be cut and retirement age increased Fig. 6-15, p. 138
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Developing vs. Developed
_____________ (Transitional, _______ World): _______ infant mortality rate because of a shortage in prenatal and pediatric care. Thus, they have _______ children to ensure some survive. ____________societies need children to help in the _______ force. Lower per capita income or poorer countries need children to provide an ______ and sometimes contraceptives are not affordable. Women ______education and _____ opportunities. ___________ (Industrial, ______ World): Usually don’t have population problems but can be linked to ______. Educated and working women tend to ________ childbearing. ________ systems support people as they age. ________ _________ and the ability to control fertility. Higher ______ of raising children causes people to have smaller families. Abortion is _______. Infant mortality higher in a country due to, for example, - contaminated drinking water - poor nutrition - poor health care- few or no educational opportunities for women.
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Where Population Growth Occurred, 1950-2010
Figure 6.3: Most of the world’s population growth between 1950 and 2010 took place in the world’s less-developed countries. This gap is projected to increase between 2010 and (Data from United Nations Population Division, The 2008 Revision and Population Reference Bureau, 2010 World Population Data Sheet) Fig. 6-3, p. 123
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_____________ Urbanization is the movement of people from ______ areas into ______ Urban areas must ______ most of its food, water, energy, minerals, & other resources because of _______ populations Large populations _________ and ________ enormous quantities of resources that can pollute the air, water & land. ________ can easily spread in urban areas because of the high density population. ____% of world’s people live in urban areas that occupy only ___% of world’s land and they consume ____% of the world’s resources. 50% of the world’s people live in urban areas that occupy only 5% of the world’s land & they consume 75% of the world’s resources.
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_____________ Environmental pressures of urbanization from population growth are reduced because _____ rates in urban areas usually are _____x’s lower than in _____ areas because cities provide ________ opportunities. Some countries, including China, ________ couples who have more than one or two children by: Raising their _______ Charging other _____ Eliminating _________ tax deductions for a couple’s third child ______ of health-care benefits, free education, food allotments and job options Thomas Malthus - “diminishing returns” He argues that rising wages and improved well-being would lead to excess reproduction among the working class. A labor surplus would then cause wages to fall below subsistence levels, resulting in starvation, disease and crime. In his view, land for food production was the limiting factor in both population growth and economic development.
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________ and _________
_______ mortality rate: The number of child and/or infant deaths. If a mother lives in an area with a ______ infant mortality rate she will tend to have _____ of children to ensure some will make it to adulthood. This ensures care for ________ parents and a ________ force. Infant mortality rate is _______ in developing countries than in developed countries. Along with life expectancy, the infant mortality rate is a good indicator of the ___________ of life of a country ___________level fertility: the number of children a couple must bear to replace _____________. Slightly higher than two children per couple. (____ in developed countries and _____ in some developing countries.) Infant mortality higher in a country due to, for example, - contaminated drinking water - poor nutrition - poor health care- few or no educational opportunities for women.
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________ Fertility Rates
__________ rate – number of children born to a woman during her ________. _______ fertility rate (_____): the average number of children a woman has during __________ years. In _______, the average global Total Fertility Rate was ____ children per woman. _____ in developed countries (down from 2.5 in 1950.) _____ in developing countries (down from 6.5 in 1950). If fertility rate drops to replacement level fertility but the population continues to grow, this is called population ___________ and can be seen in __________ shaped age structure diagrams. Birth rates and fertility rates have been _______ or ________ because: Cultural/religious practices __________ birth control. Cultural/religious practices ________ large families. Education/Employment/Status of women is ______ Reasons for decline from 1950 to present: increased/improved family planning shows fewer pregnancies, control of fertility, and choice in # of children. Increased education of women/social status shows a delay in having children. Women enter the workforce and delay having children. Reduced need for children in the workforce because of industrialization and urbanization. Improved health care allows for more children to survive.
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_______ Rates Based on current trends, it is assumed that human fertility rates will continue to ________ and life expectancy will continue to ___________. Developing countries are expected to broadly follow these demographic trends. Trends in Fertility Rates South & Central America Africa Asia Developing Developed
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Where are we going? 11 10 World population (in billions) 9 8 7 6 2010
UN high-fertility variant (2008 revision) U.S. Census Bureau (2008 update) 10 UN medium-fertility variant (2008 revision) IIASA (2007 update) UN low-fertility variant (2008 revision) World population (in billions) 9 8 7 Figure 6.A: This graph shows world population projections to 2050 from three different organizations: the UN, the U.S. Census Bureau, and IIASA. Note that the upper-most, middle, and lower-most curves of these five projections are all from the UN, each assuming a different level of fertility. 6 2010 2020 2030 2040 2050 Year Fig. 6-B, p. 130
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______ Affecting Birth Rates and Fertility Rates
The number of children women have is affected by: The _____ of raising and educating them. Availability of _________. __________. __________ and ____________ opportunities. Infant _______. Child _______ ___________ age. __________ beliefs, _________, and __________ norms Availability of _____________ and _________.
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_______ Affecting Death Rates
Death rates have _________ because of: __________ food supplies, better _______ due to Green Revolution Advances in ________. (Antibiotics and vaccines) ___________ in prenatal or neonatal care Improved __________, safer water supplies and personal hygiene due to Industrial Revolution. U.S. infant mortality is _______ than it could be (ranked ___th world-wide by CIA and ____th by Save the Childeren) due to: _________ pre- and post-natal care for poor. _______ addiction. High _________ birth rate. Fertilizers and pesticides increased crop yields More children live past childbirth
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Infant Mortality Rates, 1950-2010
Figure 6.10: This graph tracks the infant mortality rates for the world’s more-developed countries and less-developed countries, 1950–2010, with projections to 2050 based on medium population projections. (Data from United Nations Population Division) Fig. 6-10, p. 129
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Populations Can _______ from a Rising Death Rate: The _____ Tragedy
____ million killed: Many young adults die: ____ of most productive ______ Sharp drop in _____ expectancy _________ community Reduce the spread of HIV through _________ and ______ care Financial _________ and _________ Fig. 6-15, p. 134
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Population _____________
Human population growth is _______ than predicted but because of the large and increasing population size the world population is still expected to _________ substantially ________ stabilizing. Progress Towards Population Stabilization South & Central America Africa Asia Developing Developed
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Demographics in the USA
The baby ______ that followed the baby _____ was largely due to _______ marriage, ____________, and _________. Now becoming senior citizens (_________ of America) In ________, the total fertility rate in the United States was slightly > _____
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Demographics in the USA
Nearly ____ million people were added to the U.S. in _______: ___% occurred because of births outnumbering deaths ___% came from illegal and legal immigration. Population increase in recent years has been because of immigration _____ in U.S. dropped Rate of population growth has ______. Current US Population: _____________
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Legal Immigration to the U.S. between 1820 and 2006
Figure 6.11: This graph shows legal immigration to the United States, 1820–2006 (the last year for which data are available). The large increase in immigration since 1989 resulted mostly from the Immigration Reform and Control Act of 1986, which granted legal status to certain illegal immigrants who could show they had been living in the country prior to January 1, (Data from U.S. Immigration and Naturalization Service and the Pew Hispanic Center) Fig. 6-11, p. 135
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20th Century Lifestyle Changes in the U.S.
Figure 6.7: This chart lists some major changes that took place in the United States between 1900 and Question: Which two of these changes do you think were the most important? (Data from U.S. Census Bureau and Department of Commerce) Fig. 6-7, p. 132
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_________ Countries High rates of ________ use because of the availability of resources, production, and waste. Result in high levels of _________ and environmental degradation per person because of control methods, clean up, and education. The _________ of a country’s _________ growth is the Gross _________ Product (GNP) or the Gross _________ Product (GDP). The Human Development ______ is also commonly used to determine development. It is estimated that a US citizen consumes 35 X’s as much as the average citizen of India and 100 X’s as much as the average person in the world’s poorest countries. (What if everyone in the world lived like we do?) Then, poor parents in a developing country would need kids to have the same lifetime environmental impact as 2 US children. Most developed countries have a GDP that is high and a population growth rate that is low.
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__________ Countries _____, the largest, has taken drastic population control methods. By ____, _______ is predicted to pass China. __________ is projected to become 3rd (the ____ is 3rd now.) _______ is losing 600,000 people a year, after being the 4th largest country in 1950 due to pollution, crime, corruption, hyperinflation, disease, and despair. Environmentalists are concerned about _________ use because developing countries are increasing their __________ of living. Russia’s declining population is because of environmental pollution, hyperinflation, crime, corruption, disease and despair.
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Environmental Impact Equation (Paul Ehrlich Formula)
Population X affluence X technology = __________________ Estimated that a US citizen consumes ___x’s as much as the average citizen of India and ____x’s as much as the average person in the world’s poorest countries. Thus, poor parents in a developing country would need _________ kids to have the same lifetime environmental impact as ___ typical US kids.
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______ Population Control
______ has tried population control methods with modest success. Poor ________, bureaucratic inefficiency, ____ status of women and lack of support have led to ____ success. The family planning method calls for: __________ of women including basic literacy. Encouraged education of ____________ use among women & birth spacing. Possible problems include: _________/________ issues. ______ of programs.
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China’s Population Control
China has used a government-enforced program, “One-Child Policy”, to reduce the fertility rate. The One-Child Policy includes: Paid leave to women for fertility operations. Monthly Subsidy to one-child families. Tuition and job priorities for only children. Housing preferences. Additional food rations. Monetary compensation. Problems include: Preference toward gender Increase in orphans Consequences or punishment for multiple births Since 1970, China has used a government-enforced program to cut its birth rate in half and sharply reduce its fertility rate. - paid leave to women for fertility operations - monthly subsidy to single-child families - job priorities for only children - housing preferences for single-child families - additional food rations for one-child families - monetary compensation for single-child families
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Core Case Study: Slowing Population Growth in _______: A Success Story
____ billion people Currently, China’s TFR is ____ children per women. China has moved ____ million people out of poverty. China’s policy ______ couples who have more than one or two children by: Raising their taxes, charging other fees, eliminating income tax deductions for a couple’s third child, and loss of health-care benefits, food allotments and job options
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Illiteracy (% of adults) 47% 17% 36% Population under age 15 (%) 20%
Percentage of world population 17% India 20% China 1.1 billion Population 1.3 billion Population (2050) (estimated) 1.4 billion 1.6 billion Illiteracy (% of adults) 47% 17% 36% Population under age 15 (%) 20% 1.6% Population growth rate (%) 0.6% 2.9 children per women (down from 5.3 in 1970) Total fertility rate 1.6 children per women (down from 5.7 in 1972) 58 Infant mortality rate 27 Figure 9.15 Global connection: basic demographic data for India and China in (Data from United Nations and Population Reference Bureau) 62 years Life expectancy 70 years Percentage living below $2 per day 80 47 $3,120 GDP PPP per capita $5,890
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1994 Global (Cairo) Conference: Population & Development
The ________ at Cairo, Egypt, encouraged action to stabilized the world’s population at ____ billion by 2050, instead of the projected _______ billion. Provide _________ access to family-planning services Improve the ______ care of infants, children & pregnant women and improve the _______ of women by expanding education & job opportunities Encourage development of _________ population policies Increase _______ involvement in child- rearing responsibility & family planning and increase access to education for ______ Take steps to eradicate ________ STOP Describe one incentive that the government of a country could offer its citizens that would favor a reduction in the growth rate of its population. Explain how this incentive would work, and describe one possible drawback.
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INFLUENCING POPULATION SIZE
The _____ way to slow population growth is: Investing in family _________(has reduced number of _______ and ________ throughout world). Reducing _________. _________ Elevating the ________ of women by not suppressing their human rights and having paying job outside of home. Family planning in _____-developed countries Responsible for a ____% drop in TFRs Financial ________: money spent on family planning saves far more in health, education costs Women Do most of the domestic work and child care Provide unpaid health care 2/3 of all work for 10% of world’s income Discriminated against legally and culturally
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Global Contraceptive Usage
____ problems ___% pregnancies unplanned, ___% end with abortion Many couples do not have ______ to family planning
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Thomas _______ 1798 Problems with a Growing Population
“_________ ________” – Human population increases exponentially while food supplies increase at a slower linear rate Argued rising ______ and improved well-being would lead to ______ reproduction among the working class. A labor ______ would then cause wages to _____ below subsistence levels, resulting in starvation, disease and crime. Argued, land for food production was ______ factor in both population growth and economic development.
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__________ with a Growing Population
_________ for World Hunger Issues Unequal __________ of available food Loss of _______ land Increasing _________ growth rate Increasing _________ in developing countries ____________ for ensuring adequate nutrition for a growing population: Increase the number of new food ______ from a diversity of plant species Distribute food more __________ Increase land are that is dedicated to _______ production rather than _______ production Assist developing countries in efficient crop _________ systems.
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Environmental ________
____________ destroys habitats and reduces biodiversity: Farming and the creation of monocultures, housing or development projects that cause urbanization, fuel from wood, and fossil fuel recovery from mining. ________ fuel burning releases CO2: Results in climate change, change in temperature and precipitation patterns changing habitats. _________ fishing and _____ farming: Spreads disease to native fish and causes unsustainable fish populations. _________ and _________ of water: For agricultural, municipal, and industrial use reduces water supplies. Building __________: To accommodate increased amounts of trash.
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HUMAN ASPECTS ON NATURAL SYSTEMS
We have used __________ to alter much of the rest of nature in ways that threaten the _______ of many other _____ and could reduce the quality of _____ for our own _______.
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