Humans have developed the capacity to expand into habitats and climate zones that were once uninhabited and increase the carrying capacity of the environment
Ecological Footprint: impact imposed on the environment by the demand for natural resources
A Brief History:
- world grew slowly in response to the density dependent environmental factors, such as availability of food, water, and shelter
- however world population has increased exponentially
Demographers have identified four ways that humans have avoided the effects of density-dependent regulating factors:
- Expanded Geographic Range: alleviating competition for space. Life has been dispersed
- Increased Carrying Capacity: due to a shift from hunting and gathering to agriculture
- Fossil Fuels: marked the beginning of industrialization
- Advances in Public Health: reduced effects of critical population limiting factors such as malnutrition, contagious diseases and poor hygiene
Domestication Of Plants and Animals
- increase in agriculture
- raising livestock- gave food in areas that were not good for producing crops (such as rocky or steep ground)
- populations were transformed from small mobile-groups of hunter gatherers into societies in permanent towns and villages
- these people modified their natural environment through irrigation and specialized crop cultivation
- led to development of food storage practices and technologies, which resulted in surplus food production
Influence of Science, Technology, and Medicine
Human Demographics
- demographers often interested in age structure of a population
- differences in age structure are a major determinant of differences in population growth rates
Population Pyramid: tool that shows the distribution of ages among the males and females in a population
Relationship between population growth and economic development in many countries can be represented by the demographic transition model (a diagram that illustrates changes in how people live to explain shifts in population sizes)
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