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■ The determination of the age at death is still in the low sample size (Frohlich 1983). Although a

high sub-adult mortality is present, there is no
D progress on the Saar material. Because of the gen­ evidence of an increase in female skeletons when
eral poor condition of the skeletal remains, mic­
l order to increase the number of individuals which compared to the male skeletons. This can be partly
roscopical age at death determination is applied in
explained by an assumed higher life expectancy.
Further samples will hopefully clarify these prob­
can be included in the life table calculations. My lems.
l present estimaton is a life expectancy between 35 This leads me to discuss the average size of the
and 40 years at birth including several individuals
□ with a relative high age at death (55 to 65 years). population occupying Bahrain Island during the
Thus the life expectancy for the Bahrain third mil­ third millennium. Two methods can be applied :
l lennium population may prove to be significantly (1) An estimation of the number of people living

higher than in other contemporary populations in the known settlements, together with those
individuals living outside the settlements in order
in the Near East, e.g. Mesopotamia, Egypt,
l Palestine, and Anatolia. to supply the former with food and other neces­
sities. Larsen (1980) estimates the Barbar period
i Life table calculations have their disadvantages, settlement at Qalat al Bahrain to have included
however. By using this technique, it is assumed some 7000-8000 individuals, not including a pos­
that the population is stationary with no fluctua­
I tion in the birth rate, unchanging male to female sible significantly large number of individuals liv­
ratio, and with no major changes in the variability ing outside the settlement. And (2), an estimation
2 during a defined time span. Thus, the values must of the number of people necessary to produce a
I be considered with these disadvantages in mind. given number of dead in a specified time period.
The first method cannot be successfully applied
i. The life tables are, however, an important tool in to Bahrain, at present, because of the lack of data
the reconstruction and interpretation of the
i biological history, and may, in connection with the concerning settlement structures and their dis­
tribution on the island. Furthermore, the lack of
cultural finds, significantly improve the under­
i-
standing of a population represented by skeletal data and research concerning the carrying capacity
of the island in the third millennium prohibits a
i remains. successful estimation of the population size. The
The excavations at Saar, and the later excava­
tions at Hamad Town suggest a sub-adult mortal­ second method however, is applicable to the data
r ity rate similar to that found in other pre- available at the present time. In order to estimate
i industrialised societies. Hassan (1981) estimates the average number of people necessary to
produce a given number of dead, three factors are
r the sub-adult mortality rate to be between required : the total number of dead persons, the
45%-50% including an infant mortality rate of
life expectancy of the population, and the time
I about 10%. Ortner (1981) reports a 39% sub­ span.
mortality rate including a 9% infant mortality rate
j Table 1 shows the calculated population sizes
at the early Bronze Age cemetery at Bab edh- when using different life expectancies and time
i Dhra in Jordan. The similar data for the Saar mat­ periods, but keeping the maximum number of
erial is a 37.3% sub-adult mortality rate and a
10.7% infant mortality rate (Frohlich 1983). This dead persons constant (150,000). The table shows
that the required average population size
high sub-adult mortality rate means that the
i female has to produce an average of four children decreases when the time span increases and the life
expectancy decreases, thus taking an average
in her lifetime in order to maintain a stable popula­
population of 4,500 with a life expectancy of 30
tion size since almost half of her offspring will die
years at birth 1000 years to produce 150,000 dead
before reaching maturity. With a short life expec­
l tancy, she may not have adequate time for persons. Furthermore, it is seen that the required
) recuperating between the demanded number of average population increases when the time span
decreases and the life expectancy increases taking
childbirths, thus increasing the frequency of mor­ an average population of 24,000 with a life expec­
I ween births. This should result in a significantly tancy at birth, 250 years to produce 150,000 dead
tal diseases caused by the short interspacing bet-
persons. If we select a tentative life expectancy of
higher number of deceased females in the cemet­ 40 years at birth and a time span of 700 years, it
i ery with a possible influx of females from other takes an average population of 8,571 to produce
geographical areas into the society.
150,000 dead persons. :■
However, the distribution of males and females Considering the present know third millennium
I is equal in the Saar material. The slight inbalance B.C. settlement distribution and the required '
found in the preliminary data is possibly caused by
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