Exploration of population dynamics and characteristics

Biology

Exploration - Populations

Population pyramids symbolize graphically the age/gender arrangement of a population. Basically is shows how many men and women of a given age or age group are present in the population. They are detailed kinds of histograms, in which the male population is displayed on the left side of the graph, and the female population on the right; the youngest are the base of the pyramid, and the oldest are at its top. The very oldest are generally absent from the representation of the pyramid because it is unfeasible to depict this open-ended interval that includes a few of the oldest-old. Percentages are figured using both sexes combined or the total population as the denominator. A lot can be read from population pyramids as they can trace the history of a populace, as well as project its prospect. In particular, one can deduce the likelihood of population increase from a population pyramid (Population Pyramids, n.d.).

The humps in age pyramids contain the traces of precedent events such as wars, epidemics or economic depressions. The impact of these events highlight the interrelationships amid population change and financial, social, political, and health elements. By evaluating population pyramids, one can also evaluate the prospective for future growth of a population. The age pyramid of a country that has a wide base has a lot of prospective for future population growth. If the death rates go down, more and more of the numerous children in the population will live to the age of childbearing (Population Pyramids, n.d.).

This is tremendously useful information. If one can project what proportion of the U.S. population will reach retirement age in 2020 or in 2050, then they can get a sense of the troubles that face social security. If one can project how fast the quantity of people living in areas where malaria is widespread, then they can predict the augments in budget allocated to fighting malaria that will be necessary to avoid growing transmission rates. Demographic data and projections are therefore a crucial part of decision making in public health (Population Pyramids, n.d.).

If a pyramid is broad-based, it means that there is a big proportion of young people and fewer adults, which leads to a rapidly increasing population. This type of pyramids will taper very quickly towards the top to represent the older age groups, and is very narrow at the top. Developing countries normally have high birth rates or wide bases due to things such as:

lack of contraception or family planning, or religions that do not permit contraception having a lot of children in a family augments the chance that some will survive until adulthood and then can care for their parents when they are old, and children can work on family farms or earn revenue for the family if a child dies, the mother may then have another replacement child which is both harmful to the health of the mother and the new child

Developing countries have narrow tops because less people live until old age, due to a lot of conditions associated with developing countries, such as: