population dynamics

Examples of population dynamics in the following topics:

• Introduction

  • Demography is the study of human population dynamics.
  • It encompasses the study of the size, structure and distribution of populations, and how populations change over time due to births, deaths, migration, and aging.

• Population Demography

  • Demography is the study of population dynamics, using statistical and mathematical tools.
  • Understanding the population dynamics of the carp will help biologists develop and implement measures that reduce its population, allowing scientists to model the statistics of carp populations.
  • Populations are dynamic entities, consisting of all of the species living within a specific area.
  • Demography, the statistical study of population dynamics, uses mathematical tools to investigate how populations respond to changes in their biotic and abiotic environments.
  • The term "demographics" is often used in discussions of human populations, but demographic approaches can be applied to all living populations.

• The Study of Population Dynamics

  • Demography, or the study of population dynamics, is studied using tools such as life tables and survivorship curves.
  • Population size, density, and distribution patterns describe a population at a fixed point in time.
  • To study how a population changes over time, scientists must use the tools of demography: the statistical study of population changes over time.
  • Biological features of the population also affect population changes over time.
  • The demographic characteristics of a population are the basic determinants of how the population changes over time.

• Age Structure, Population Growth, and Economic Development

  • The variation of populations over time, also known as population dynamics, depends on biological and environmental processes that determine population changes.
  • With knowledge of this age structure, population growth can be more accurately predicted.
  • Some developed countries, such as Italy, have zero population growth.
  • The stable population diagram is rounded on top; the older part of the population is a larger proportion of the population than in the other age diagrams.
  • Explain how age structure in a population is associated with population growth and economic development

• Ecosystem Dynamics

  • Ecosystems are dynamic entities controlled both by external and internal factors.
  • In 1993, a change in ecosystem dynamics caused a disease outbreak in a human population.
  • The higher population of deer mice meant more mouse droppings and more opportunities to transmit hantavirus to humans.
  • In early 1993, the rainfall caused an increase in vegetation, which caused an increase the local deer mice population.
  • Hantavirus infected the high deer mouse population and was quickly transmitted to humans via aerosolized mouse droppings.

• Population Growth

  • Population growth can be modeled by an exponential equation.
  • ${\Delta}P$ denotes the change in population.
  • As such, another variable is important when studying population demographics and dynamics.
  • It is the Population Growth Rate ($PGR$).
  • A positive growth rate indicates an increasing population size, while a negative growth rate is characteristic of a decreasing population.

• Three Demographic Variables

  • Demography is the statistical study of human populations.
  • It can be a very general science that can be applied to any kind of dynamic living population, or one that changes over time or space.
  • (Births - Deaths) +/- ((In-Migration) - (Out Migration)) = Population Change.
  • This basic equation can be applied to populations and subpopulations.
  • For example, the population size of ethnic groups or nationalities within a given society or country is subject to the same sources of change as the national population.

• Predation, Herbivory, and the Competitive Exclusion Principle

  • The most-often-cited example of predator-prey dynamics is seen in the cycling of the lynx (predator) and the snowshoe hare (prey), which is based on nearly 200-year-old trapping data from North American forests .
  • When the lynx population grows to a threshold level, they kill so many hares that the hare population begins to decline.
  • The cycling of lynx and snowshoe hare populations in Northern Ontario is an example of predator-prey dynamics.
  • As hare populations increase,the lynx populations also increase due to increased food supplies.
  • This results in a decrease in the lynx population.

• The Dynamics of Poverty

  • Poverty operates in a dynamic cycle, with the effects of poverty increasing the likelihood that it will be transferred between generations.
  • The basic premise of the poverty cycle the idea that poverty is a dynamic process—its effects may also be its causes.
  • Slum-dwellers, who make up a third of the world's urban population, live in poverty no better, if not worse, than rural people, who are the traditional victims of poverty in the developing world.

• Predator-Prey Systems

  • The predator–prey equations are a pair of first-order, non-linear, differential equations frequently used to describe the dynamics of biological systems in which two species interact, one a predator and one its prey.
  • The food supply of the predator population depends entirely on the prey populations.
  • The rate of change of population is proportional to its size.
  • In the predator equation, $\delta xy$ represents the growth of the predator population.
  • The predator population follows the prey population.