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P About H E M The H To And

HOW MANY PEOPLE ON EARTH?

On 1 January 2010 the population of the Earth was approximately 6.9 billion people. Mark 6 billion was completed in 1999. According to scientists, the level of 7 billion will be eliminated at the end of 2010.

Now how did the growth of the population of our planet:

The end of the Paleolithic period (about 15 thousand years BC) 3 million
The late Neolithic (2 thousand years BC) 50 million
The beginning of our era 230 million
The end of the 1st Millennium A.D. 275 million
1800 1 billion
1900 1.6 billion
1960 3 billion
1993 5.5 billion
1999 6 billion
2003 6.3 billion
2006 6.5 billion

...

The forecast for 2050

 

9.2 billion

Graphically it looks like this:

The population on Earth

As can be seen from this graph, somewhere 8-10 thousand years ago there was a jump in the growth rate of the number of people on the planet. And in the XVIII century there was another pull, the population growth rate was much higher than before. What explains these races?

The main factor that determines the population on Earth is human activities. Up to 10 thousand BC people were mostly engaged in gathering and hunting. The population then was about 10-15 million people (the number of large modern cities, such as new York or Moscow). Many scientists believe that the primitive people was very high fertility - 35-55 people in the year 1000 and the same high mortality. During his life, the woman had about 5-10 children, many of whom died in childhood. The average life expectancy was only 30 years.

About 10 thousand years BC was an important event - the agricultural revolution: people have domesticated some animals and learned to grow some plants. The man moved to the production of products. And it is possible to increase consumption, and made possible a higher population density than in the aggregate economy. Happened the first surge of population, and the population gradually increased several times - about 50 million.

The population on the Earth and human activities

Several thousand years on Earth there was a relatively stable population size. People could not control the weather, and therefore population growth in the productive years were destroyed by famine in the lean years. The population was often reduced as a result of wars, epidemics and famine.

In the XVIII century there was another major event - the industrial revolution: manual labor was gradually supplanted by the work of machines. It was possible to produce much more benefits with lower costs. In addition, there was a leap in the development of medicine, which helped to reduce mortality from many diseases. The world's population has been increasing rapidly - there has been a population explosion.

Before the 70-ies of XX century the population grew very quickly (as mathematicians would say - according to the hyperbolic law, that is, when the growth rate of population is proportional to the square of its number). Then the rate of population growth has decreased. Now the population growth is happening in other law - logistics:

The logistic curve

We make such a model, in which population growth is approximately equal to the death rate, and the total population remains stable. The reason for this phenomenon scientists believe the fertility decline that occurred first in economically developed countries, but now in the Third world countries. Parents in the modern world prefer "high quality" to grow 1-2 children than to pump a lot of children. The death rate in modern world, too, reduced: thanks to the development of medicine increase life expectancy. The transition from high fertility and mortality to low has called demographic transition.

Now we can confidently say that most people in the twenty-first century will live in cities. The average life expectancy of close to 90 years, and the maximum, it will probably be for 130 years. Older people on the planet will be two times more than children.

By the way...

• How many people can feed the Earth? There are many opinions, from the most pessimistic (1 billion or less) to very optimistic. Academician Sergey Kapitsa believes that "under reasonable assumptions, the Earth can sustain for a long time up to 15 - 25 billion people."

• ...Until you read this page (20 minutes, no more, huh?) on Earth was added 4.5 thousand people. This is a whole village!


 


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Total votes: 1083

Your comments:

Lera
2014-03-21 16:26:09
And people still say that abortion is bad. India on abortion ahead of the rest. Imagine if all women would be at least 2 children. This is natural selection
Rus
2014-03-18 07:54:29
No one will be able to read, this is not the correct statistic may be somewhere 3 billion, not 7. The census is a political question if economic.
Xena
2014-03-12 16:06:06
nevernice soon the Earth will soon newcommit all of us
Sanya
2014-03-12 16:03:16
very best ,and I didn't know that 20 minutes is born as many children
I
2014-02-20 22:50:19
needed urgently sweep, the earth will not endure so much..
Thomas
2014-02-08 21:19:16
...and how to cut sharply?
Vita
2014-01-29 20:39:13
class
^^^Mahongo
2014-01-04 14:30:18
Lev Andreevich, I don't understand! Everything was as it is written!
And in GENERAL... and why would anyone on the ears to go
Anna
2013-11-27 12:38:27
class
Lev Andreevich
2013-10-22 06:48:24
Pay attention to the first table in this article between -60 1900's, this surge simply could not be with all the world warriors, revolutions and disasters data is highly questionable and not anyone else has fixed this heresy I's ears anybody, Nevermind))

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