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 serious food crisis in the Horn of Africa and to be answeredimmediately. " Therefore, the Spanish Red Cross is strengthening its humanitarian intervention, in  collaboration with the International Red Cross and RedCrescent, fundamentally, with the Red Cross in Ethiopia, Kenya RedCross and Red Crescent Somalia. To date, the Spanish Red Cross has allocated 100,000 euros of itsemergency fund to support the Red Cross has redirected these countries and their delegations work in the  field to tackle the crisis , while maintaining involvement through programs food security  and early warning. || [] || Alyson || At the global level, human population growth is //one// significant cause of environmental problems, for two reasons. First, Population growth has necessitated global increase in food production. More and more land has been taken over for food production to feed the growing population, to provide housing and infrastructure for that population and now, to provide land for energy crop production. And oceanic fishing has increased in intensity. Second, much attention has been given to the high per capita levels of consumption and waste production in industrial countries, leading to increased climate changing emissions. But the fact is that the massive population increase in these countries has greatly increased this harmful effect. || [] || Winniver || Globally, the growth rate of the human population has been declining since peaking in 1962 and 1963 at 2.20% per annum. In 2009, the estimated annual growth rate was 1.1%. The CIA World Factbook gives the world annual birthrate, mortality rate, and growth rate as 1.915%, 0.812%, and 1.092% respectively. The last one hundred years have seen a rapid increase in population due to medical advances and massive increase in agricultural productivity made possible by the Green Revolution. || [] || Anthropologists believe the human species dates back at least 3 million years. For most of our history, these distant ancestors lived a precarious existence as hunters and gatherers. This way of life kept their total numbers small, probably less than 10 million. However, as agriculture was introduced, communities evolved that could support more people. World population expanded to about 300 million by A.D. 1 and continued to grow at a moderate rate. But after the start of the Industrial Revolution in the 18th century, living standards rose and widespread famines and epidemics diminished in some regions. Population growth accelerated. The population climbed to about 760 million in 1750 and reached 1 billion around 1800. || [] || The recent rapid increase in human population over the past two centuries has raised concerns that humans are beginning to overpopulate the Earth, and that the planet may not be able to sustain present or larger numbers of inhabitants. The population has been growing continuously since the end of the [|Black Death], around the year 1400; at the beginning of the 19th century, it had reached roughly 1,000,000,000 ( [|1 billion] ). Increases in medical technology have led to rapid population growth on a worldwide level. Current projections show a steady decline in the population growth rate, with the population [|expected] to reach between 8 and 10.5 [|billion] between the year 2040 and 2050. In May 2011, The United Nations increased the medium variant projections to 9.3 billion for 2050 and 10.1 billion for 2100. || [] || Anyone who examines world population growth over the past two centuries certainly must be astounded, and quite possibly alarmed. The global population reached one billion in 1804. In 1927, some 123 years later, it passed two billion. Sixty years later, in 1987, the world population was five billion, and 12 years later, in October 1999, it is estimated to have passed six billion. Small wonder that many are concerned about what this bodes for our future. Due to the momentum represented by steeply pyramidal age distributions, population growth surely will continue for one to several generations. Most of that growth will occur in developing nations. An eventual world population of 8-12 billion is expected by the end of the century. But estimates change frequently. || [|http://www.globalchange.umich.edu/globalchange2/current/lectures/human_pop/human_pop.html#Past] || Alyson || As of October 21, 2011, the United States has a total resident population of 312,421,000, making it the third most populous country in the world. It is a very urbanized population, with 82% residing in cities and suburbs as of 2008 (the worldwide urban rate is 50.5%. The total fertility rate in the United States estimated for 2009 is 2.01 children per woman, which is below the replacement fertility rate of approximately 2.1.However, U.S. population growth is among the highest in industrialized countries,since the vast majority of these have below-replacement fertility rates and the U.S. has higher levels of immigration. The United States Census Burea shows population increases ranging between 0.85% and 0.89% for the twelve-month periods ending in 2009. Nonetheless, though high by industrialized country standards, this is below the world average annual rate of 1.19% || [] || Birth rate (b) − death rate (d) = rate of natural increase (r).birth rate expressed as number of births per 1000 per year (currently 14 in the U.S.);death rate expressed as the number of deaths per 1000 per year (currently 8 in the U.S.);So the rate of natural increase is 6 per thousand (0.006 or 0.6%).Although the value of r is affected by both birth rate and death rate, the recent history of the human population has been affected more by declines in death rates than by increases in birth rates. The graph shows birth and death rates in Mexico since 1930. The introduction of public health measures, such as better nutritiongreater access to medical careimproved sanitationmore widespread immunizationhas produced a rapid decline in death rates, but until recently there was no corresponding decline in birth rates. In 2010, r is 1.4%. (Data from the Population Reference Bureau.)Although death rates declined in all age groups, the reduction among infants and children had — and will continue to have — the greatest impact on population growth. This is because they will soon be having children of their own. This situation, resulting in a rapid rate of population growth, is characteristic of many of the poorer regions of the world. || [] || In previous lectures, we have described how human cultural development was closely tied to changes in the natural environment. Successive cultural revolutions, such as the agricultural revolution, have led to surges in population. Figure 1 summarizes again the historical record, typical of a "J-shaped" growth, with humans filling new niches and (perhaps) not yet reaching a limiting carrying capacity. One feature to note in this plot is the lack of huge fluctuations associated with famines or wars. In fact, the nature of J-shaped (exponential) growth is such that episodic reductions due to such catastrophes usually do not affect the inexorable and overpowering upward acceleration in population size. An exception is the period of the "[|black death]" in Europe, which produced a noticeable but small downward spike in the curve. The wholesale loss of life due to world wars of the 20th century produced only small perturbations to the upward trend. || [] || Jackeline || media type="custom" key="10997530" || [] || Winniver || As the world population continues to grow geometrically, great pressure is being placed on arable land, water, energy, and biological resources to provide an adequate supply of food while maintaining the integrity of our ecosystem. According to the World Bank and the United Nations, from 1 to 2 billion humans are now malnourished, indicating a combination of insufficient food, low incomes, and inadequate distribution of food. This is the largest number of hungry humans ever recorded in history. In China about 80 million are now malnourished and hungry. Based on current rates of increase, the world population is projected to double from roughly 6 billion to more than 12 billion in less than 50 years. As the world population expands, the food problem will become increasingly severe, conceivably with the numbers of malnourished reaching 3 billion. || [] || Alyson || The increase in the average length of a human life affected the amount of children they could reproduce during their reproductive years. In addition, improvements in basic health meant that many, if not all, of the offspring would survive until they too could have children. Whereas many babies used to die as infants, modern medicine coupled with better nutrition during pregnancy made it possible for a mother to give birth to many healthy children. It became common to see multi-generational families, with grandparent and great grandparent surviving to see their descendants. The population growth occurred quite rapidly because people had more children and survival until old age became common. However, as Western nations were just beginning to realize it was time to have fewer children, less developed countries began to pick up on many of these advances, and their populations exploded in growth as well. || [] || Of the 6 billion people, about half live in poverty and at least one fifth are severely undernourished. The rest live out their lives in comparative comfort and health. The factors affecting global human population are very simple. They are fertility, mortality, initial population, and time. The current [|growth rate] of ~1.3% per year is smaller than the peak which occurred a few decades ago (~2.1% per year in 1965-1970), but since this rate acts on a much larger population base, the absolute number of new people per year (~90 million) is at an all time high. The stabilization of population will require a reduction in fertility globally. In the most optimistic view, this will take some time. ||  || Yordelis || Global Trends in Natural Population Increase A “natural population increase” occurs when the birth rate is higher than the death rate. While a country’s population growth rate depends on the natural increase and on migration, world population growth is determined exclusively by the natural increase. Around the world, death rates gradually decreased in the late 19th and the 20th centuries, with death rates in the developing world plummeting after World War II thanks to the spread of modern medicine. In much of the developing world the decline in death rates preceded the decline in birth rates by 20 years or more, resulting in record-high rates of population growth of 3 percent or even 4 percent a year. Since the 1960s birth rates have also been declining rapidly in most developing countries except those in Sub-Saharan Africa and the Middle East. This trend in birth rates in the developing world is comparable to what took place in Europe and the United States in the 19th century. || [] || Winniver || China’s slowing population growth is a product of its family planning system and the policy of limiting urban residents to one child per woman, Ma Jiantang, head of the National Statistics Bureau, told reporters in Beijing yesterday. Annual population growth was 0.57 percent between 2000 and 2010, half a percentage point lower than the 1.07 percent annual growth between 1990 and 2000, according to the census figures. The one-child policy, which has resulted in millions of aborted female fetuses, has led to men making up 51.3 percent of the population, with 34 million more men than women. Most countries have more women than men, including the U.S., where 50.3 percent of the population was female in 2010, according to U.S. census data. || [] || Alyson || In a demographic shift touching every corner of the U.S., the Hispanic population grew faster than expected and accounted for more than half of the nation's growth over the past decade, with the group's increase driven by births and immigration. The Census Bureau in its first nationwide demographic tally from the 2010 headcount said Thursday the U.S. Hispanic population surged 43%, rising to 50.5 million in 2010 from 35.3 million in 2000. Latinos now constitute 16% of the nation's total population of 308.7 million. The Hispanic population is under-represented in the electorate and politically because of demographic factors," including the high share under age 18 and the high number of immigrants, said Jeffrey Passel, a demographer at the Pew Hispanic Center. "Their presence in the electorate will increase over time. || [] || Dayan || media type="youtube" key="Jn_yeVeEI70" height="315" width="420" || [] || In the developing world, not only are there many females capable of reproduction, but there are many more young females who are of potential mothers. Thus, the shape of the population-age pyramid for the developing world indicates that the population will continue to grow aggressively for the near future as the cohort of fertile females gets larger each year, fed from the lower parts of the pyramid. It takes many tens (perhaps hundreds) of years to steepen the slopes of the population-age pyramid. Such a steepening is essential before populations can become stable. Intensive efforts to control population have been implemented in various countries. In China, aggressive population control via a one-child family policy is bringing remarkable change to age structure and population size. Click here for a short case study and dynamic graphic representation of China's future population and food security. As can be seen, the aggressive population planning policies in India (discussed further in the next lecture) have served to steepen the pyramid - but only marginally so. The pyramid for 1991 has a long way to go before it resembles the stable structure seen in the developed world. || [] || Winniver || media type="youtube" key="KbwNgI_gFMI" width="425" height="350" || [] || Alyson || media type="youtube" key="mWHo_ega0RU" width="425" height="350" || [] || Dayan || media type="youtube" key="BVw181tlSMk" width="425" height="350" || [] || Yordelis || May 11 2011 The world population has grown tremendously over the past two thousand years. In 1999, the world population passed the six billion mark. Latest official current world population estimate, for mid-year 2010, is estimated at **6,852,472,823**.The chart below shows past world population data back to the year one and future world population projections through the year 2050. || [] || Dayan || Population growth did not become exponential until around 1750. Before that, high mortality counterbalanced the high fertility needed by agrarian parents. Death rates were high and life expectancy was low; life expectancy at birth was in the range of twenty to forty years (most likely around thirty years) until the middle of the eighteenth century. This high mortality was a function of several factors, including poor nutrition, which led directly to deaths through starvation and indirectly through increasing susceptibility to disease; epidemics; and, quite possibly, infanticide and geronticide, especially during times of food shortage.
 * **Name** || **Information** || Link ||
 * Solis, Jackeline || <span class="hps" style="font-family: 'Comic Sans MS',cursive;">Food, water and sanitation, health and shelter are basic needs of peopleaffected by
 * **Gil,**
 * Yordelis** || Especially since 1960, several developments have dramatically reduced infant and child mortality throughout the world: the use of DDT to eliminate mosquito-borne malaria; childhood immunization programs against cholera, diphtheria and other often-fatal diseases; and antibiotics. During the same period, the "Green Revolution" greatly boosted food output through the cultivation of new disease-resistant rice and other food crops, and the use of fertilizers and more effective farming methods. These changes have contributed to a dramatic increase in human population growth rates. The Earth's population reached 6 billion in September, 1999 ([|Updated total]). It will increase this decade by another billion, the fastest population growth in history. It was only 2 billion in 1930, so today's older generation was the first in history to see a tripling of the Earth's population during their lifetimes! Every **second**, three people are added to the world; every **day** a quarter of a million (2 times the population of the city of Irvine) are added. Every **year**, about 87 million people (about the population of Mexico, or 3x the population of California, or the combined populations of the Philippines and South Korea) are added to the world. During the next **2.5 years**, the equivalent of the U.S. population will be added to the planet. During the coming **decade** the increased population of one billion people is the equivalent of adding an extra China to the world's population. A recent joint statement by the U.S. National Academy of Sciences and the British Royal Society finds that population is growing at a rate that will lead to **doubling by 2050**. || [] ||
 * Dominguez,
 * Morales,
 * <span style="font-family: 'Comic Sans MS',cursive;">Solis, Jackeline || <span style="font-family: 'Comic Sans MS',cursive;">The **world population** is the total number of living [|humans] on the planet [|Earth], currently estimated to be **6.97 billion** by the [|United States Census Bureau] as of October 15, 2011. [|[1]] The world population has experienced [|continuous growth] since the end of the [|Great Famine] and [|Bubonic Plague] in 1350, when it was about 370 million. [|[2]] The highest rates of growth—increases above 1.8% per year—were seen briefly during the 1950s, for a longer period during the 1960s and 1970s; the growth rate peaked at 2.2% in 1963, and declined to 1.1% by 2009. Annual births have reduced to 140 million since their peak at 173 million in the late 1990s, and are expected to remain constant, while deaths number 57 million per year and are expected to increase to 80 million per year by 2040. Current projections show a continued increase of population (but a steady decline in the population growth rate), with the global population expected to reach between 7.5 and 10.5 [|billion] by the year 2050. || [] ||
 * **Gil,**
 * Yordelis** || For the last 50 years, world population multiplied more rapidly than ever before, and more rapidly than it is projected to grow in the future. In 1950, the world had 2.5 billion people; and in 2005, the world had 6.5 billion people. By 2050, this number could rise to more than 9 billion (see chart "World Population Growth, 1950-2050").
 * Solis, Jackeline || **Overpopulation** is a condition where an [|organism] 's numbers exceed the [|carrying capacity] of its [|habitat] . The term often refers to the relationship between the [|human population] and its [|environment], the Earth. [|Steve Jones] , head of the biology department at [|University College London] , has said, "Humans are 10,000 times more common than we should be, according to the rules of the animal kingdom, and we have agriculture to thank for that. Without farming, the world population would probably have reached half a million by now." The world’s population has significantly increased in the last 50 years, mainly due to [|medical advancements] and substantial increases in [|agricultural] productivity.
 * Morales, Winniver || === Future Global Population Growth ===
 * Dominguez,
 * **Gil,**
 * Yordelis** || Human Population Growth The Rate of Natural Increase (r)
 * **Ana Pedreschi** || ===** Past Human Population Growth **===
 * Solis,
 * Morales,
 * Dominguez,
 * Ana Pedreschi || The human population growth of the last century has been truly phenomenal. It required only 40 years after 1950 for the population to double from 2.5 billion to 5 billion. This doubling time is less than the average human lifetime. The world population passed 6 billion just before the end of the 20th century. Present estimates are for the population to reach 8-12 billion before the end of the 21st century. During each lecture hour, more than 10,000 new people enter the world, a rate of ~3 per second!
 * Gil,
 * Solis, Jackeline || media type="custom" key="11031996" || [] ||
 * Morales,
 * Dominguez,
 * Ruiz,
 * Ana Pedreschi || The top figure shows the population-age pyramid for the developed world and the bottom figure is for the developing world. The figure illustrates the pyramids for the years 1975 (pink) and 2000 (blue). The population/age structure of the developed world represents that of a stable (or nearly stable) population. Here, the pyramid is more rectangular than for a rapidly growing population (bottom) where there is a much larger number of young people. The bottom figure (typical for countries like Mexico, Malaysia, India, etc.) is more triangular and shows how a rapidly growing population is dominated by young people. The female side of the diagram is particularly important in understanding future growth. This is because fertility is largely controlled by the number of females in their reproductive years (roughly ages 15 - 40).
 * Morales,
 * Dominguez,
 * Ruiz,
 * Gil,
 * Ruiz,

|| [] || Anyone who examines world population growth over the past two centuries certainly must be astounded, and quite possibly alarmed. The global population reached one billion in 1804. In 1927, some 123 years later, it passed two billion. Sixty years later, in 1987, the world population was five billion, and 12 years later, in October 1999, it is estimated to have passed six billion. Small wonder that many are concerned about what this bodes for our future. Due to the momentum represented by steeply pyramidal age distributions, population growth surely will continue for one to several generations. Most of that growth will occur in developing nations. An eventual world population of 8-12 billion is expected by the end of the century. But estimates change frequently. According to a report from the United Nations Population Fund, based on 1998 analyses (see [|The State of World Population 1999)], projections for the future global population are being revised downward. The projection for 2050 now is 8.9 billion (medium variant), substantially lower than the 1996 projection of 9.4 billion. The major reason for the lower projection is good news: global fertility rates have declined more rapidly than expected, as health care, including reproductive health, has improved faster than anticipated, and men and women have chosen to have smaller families. About one-third of the reduction in long-range population projections, however, is due to increasing mortality rates in sub-Saharan Africa and parts of the Indian subcontinent. The most important factor is HIV/AIDS, which is spreading much faster than previously anticipated. The HIV/AIDS epidemic is having a devastating effect on Africa. Estimates released in 1998 by UNAIDS and the World Health Organization indicate that global HIV infections increased 10 per cent in 1998 to 33.4 million people worldwide. In 1999 alone, an estimated 5.8 million people contracted the virus that causes AIDS. Fig. 8 shows the likely impact of AIDS in Sub-Saharan Africa, comparing population projections with and without AIDS in the 29 most-affected countries, 1980-2050. || Dayan || The world's current (overall as well as natural) growth rate is about 1.14%, representing a doubling time of 61 years. We can expect the world's population of 6.5 billion to become 13 billion by 2067 if current growth continues. The world's growth rate peaked in the 1960s at 2% and a doubling time of 35 years. Most European countries have low growth rates. In the United Kingdom, the rate is 0.2%, in Germany it's 0.0%, and in France, 0.4%. Germany's zero rate of growth includes a natural increase of -0.2%, without immigration, Germany would be shrinking, like the Czech Republic. Many Asian and African countries have high growth rates. Afghanistan has a current growth rate of 4.8%, representing a doubling time of 14.5 years! If Afghanistan's growth rate remained the same (which is very unlikely and the country's projected growth rate for 2025 is a mere 2.3%), then the population of 30 million would become 60 million in 2020, 120 million in 2035, 280 million in 2049, 560 million in 2064, and 1.12 billion in 2078. || [] || Dayan || The human population will top seven billion this year—more than double what it was just 50 years ago, experts say. And these next 39 years are expected to bring about some big shifts among the biggest countries. By 2050, India will have surpassed China as the world’s largest population, growing from 1.24 billion to 1.69 billion as China shrinks from 1.35 billion to 1.3 billion. And Africa’s population will likely have more than doubled by then, with Nigeria slated to catch up to the U.S. numbers. The figures are described in a new report published in the July 29 issue of //Science//. Along with sheer numbers, global life expectancy is projected to rise as well: from age 69 worldwide this year to 76 in 2050. By then, nearly a quarter of the world’s population is expected to be over 60—which is about double the proportion that it is today. || [] || Populations in certain regions will grow; elsewhere, human numbers will stabilize or even decline. Within countries, populations will continue to shift from rural to urban areas, while becoming increasingly older and better educated. Migration between countries will be an increasingly important factor in international relations and the composition of national populations. Fig 7 shows the regional make-up of the world population, 1950-2050. Clearly, the fraction that lives in less-developed regions will dominate, continuing a trend that already is well underway. In 1960, 70 per cent of the global population lived in less-developed regions. By late 1999, the less-developed regions had grown to comprise 80 per cent. Of the projected growth of the world population by 2025, 98 per cent will occur in these regions. Africa, with an average fertility rate exceeding five children per woman during the entire period, has grown the fastest among regions. There are almost three times as many Africans alive today (767 million) as there were in 1960. Asia, by far the most populous region, has more than doubled in size (to over 3.6 billion), as has Latin America and the Caribbean. In contrast, the population of Northern America has grown by only 50 per cent, and Europe’s has increased by only 20 per cent and is now || [] ||
 * Ana Pedreschi || === Future Global Population Growth ===
 * // Figure 8. //** ||  || [] ||
 * Ruiz,
 * Ruiz,
 * Ana Pedreschi || === Changing Distribution of World Population  ===