Organisation at Population Level 45
Table 3.2 juxtaposes global population in some characteristic dates with
the average yearly increase rate in the intermediate periods, based on an
exponential model. It also shows the theoretical times of population doubling for each intermediate period, which constitute a characteristic index
of the increase.
According to archaeological findings, agricultural communities had
begun to function in several sites around 10,000 BC. With the beginning of
the agricultural period, the increase of human population was accelerated,
mainly due to a decrease of mortality. The development of agriculture gave
man enough food and allowed him to settle in one place. It also gave to
members of the rural society the possibility to turn to other activities that
assisted the rise of the general life standard. Thus, the natural dangers and
other negative factors for human life were eased off; as a result, the average life expectancy rose above the initial level of 20–25 years. According
to other views, the increased acceleration is rather due to the increase of
natality than to the decrease of mortality. Man, as a moving hunter and
fruit gatherer, left perhaps long time intervals between births, which were
imposed by the mother’s inability to carry along more than one child as
well as by the need for nursing for at least 3 years, since the available hard
food was unsuitable for very small children. Therefore, one of the most
“human” characteristics, birth control, probably appeared many thousands
Table 3.2 Global Population and Increase Percentages
Date
Population
(millions)
Mean Yearly
Increase
(percentage %)
Doubling Time
–8000
5
0.0477
1453
1650
500
0.3466
200
1850
1000
0.916
76
1950
2500
1.880
37
1975
4000
1.887
37
1988
5112
1.433
49
2000
6071
0.787
88
2050 (prob.)
9000
Source: Hadjibiros, K. (2007). Ecology. Ecosystems and Environmental
Protection, 3rd edition. Symmetria, Athens (in Greek). With permission.
Table 3.2 juxtaposes global population in some characteristic dates with
the average yearly increase rate in the intermediate periods, based on an
exponential model. It also shows the theoretical times of population doubling for each intermediate period, which constitute a characteristic index
of the increase.
According to archaeological findings, agricultural communities had
begun to function in several sites around 10,000 BC. With the beginning of
the agricultural period, the increase of human population was accelerated,
mainly due to a decrease of mortality. The development of agriculture gave
man enough food and allowed him to settle in one place. It also gave to
members of the rural society the possibility to turn to other activities that
assisted the rise of the general life standard. Thus, the natural dangers and
other negative factors for human life were eased off; as a result, the average life expectancy rose above the initial level of 20–25 years. According
to other views, the increased acceleration is rather due to the increase of
natality than to the decrease of mortality. Man, as a moving hunter and
fruit gatherer, left perhaps long time intervals between births, which were
imposed by the mother’s inability to carry along more than one child as
well as by the need for nursing for at least 3 years, since the available hard
food was unsuitable for very small children. Therefore, one of the most
“human” characteristics, birth control, probably appeared many thousands
Table 3.2 Global Population and Increase Percentages
Date
Population
(millions)
Mean Yearly
Increase
(percentage %)
Doubling Time
–8000
5
0.0477
1453
1650
500
0.3466
200
1850
1000
0.916
76
1950
2500
1.880
37
1975
4000
1.887
37
1988
5112
1.433
49
2000
6071
0.787
88
2050 (prob.)
9000
Source: Hadjibiros, K. (2007). Ecology. Ecosystems and Environmental
Protection, 3rd edition. Symmetria, Athens (in Greek). With permission.