There should be one child policy worldwide like in China.
Scary how much the population has exploded!
La población humana ha aumentado exponencialmente y en poco tiempo alcanzará limites muy altos haciendo que el planeta no de abasto para tanta gente. esto empezó a notarse desde la época de los 50 en el siglo pasado.
Population dynamics is a complex system of physical statistics.
What are human principles?
Population growth shares complex ties to poverty and inequality, exacerbating the gap between the wealthy and the poor, and complicating access to Earth's finite resources.
A population is a group of individuals living together in a given area at a given time. Changes in populations are termed population dynamics. The current human population is made up of all of the people who currently share the earth.
Every birth and death is a part of human population dynamics. Each time a person moves from one location to another, the spatial arrangement of the population is changed, and this is an element of population dynamics. While humans are unique in many ways as a species, they are subject to many of the same limiting forces and unexpected events of all populations of organisms.
In 1999, the human population crossed the six billion mark. At current growth rates, the population will double within 50 years. Long ago, when the human population was small, the doubling of the population had little impact on the human population or its environment. However, with the size of today's population, the effect of doubling the population is quite significant.
Already, most of the people of the world do not have adequate clean water, food, housing and medical care, and these deficiencies are at least partially the result of over-population. As the population continues to grow, competition for resources will increase. Natural disasters and political conflicts will exacerbate the problems, especially in the more stressed regions of developing nations. The survivors of this competition will likely be determined by factors such as place of birth and educational opportunities.
Human populations are not stagnant. They naturally change in size, density and predominance of age
groups in response to environmental factors such as resources availability and disease, as well as social and cultural factors. The increases and decreases in human population size make up what is known as human population dynamics.
If resources are not limited, then populations experience exponential growth. A plot of exponential growth over time resembles a "J" curve. Absolute numbers are relatively small at first along the base of the J curve, but the population rapidly skyrockets when the critical time near the stem of the J curve is reached.
For most of the history of modern humans (Homo sapiens), people were hunter-gatherers. Food, especially meat from large mammals, was usually plentiful. However, populations were small because the nomadic life did not favor large family sizes. During those times, the human population was probably not more than a few million worldwide. It was still in the base of the J growth curve.
With the end of the last Ice Age, roughly 10,000 years ago, the climates worldwide changed and many large mammals that had been the mainstay of human diet became extinct. This forced a change in diet and lifestyle, from one of the nomadic hunter-gatherer to that of a more stationary agricultural society. Humans began cultivating food and started eating more plants and less meat.
Having larger families was possible with the more stationary lifestyle. In fact, having a large family increasingly became an asset, as extra hands were needed for maintaining crops and homes. As agriculture became the mainstay of human life, the population increased.
The next big influence on the human population occurred with the start of the Industrial Revolution in the late 18th century. With the advent of factories, children became valuable labor resources, thereby contributing to survival, and family sizes increased. The resulting population boom was further aided by improvements in agricultural technology that led to increased food production. Medical advancements increased control over disease and lengthened the average life-span.
By the early 19th century, the human population worldwide reached one billion. It was now in the stem of the J curve graph. As the world approached the 20th century, the human population was growing at an exponential rate.
During the 20th century, another important event in human population dynamics occurred. The birth
rates in the highly developed countries decreased dramatically. Factors contributing to this decrease included:
• a rise in the standard of living,
• the availability of practical birth control methods
• the establishment of child education and labor laws.
In contrast, the populations in less well-developed countries continue to soar. Worldwide, the human population currently exceeds six billion and continues to grow exponentially. How much more the world population will grow is a topic of intense speculation. One thing is certain: exponential growth cannot continue forever, as earth's resources are limited.
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