How would you describe a stable population?
How would you describe a stable population?
The term stable population refers to a population with an unchanging (but possibly nonzero) rate of growth and an unchanging age composition (i.e., the population pyramid does not change in shape) as a result of age-specific birth rates and age-specific death rates that have remained constant for a sufficiently long …
What factors stabilize population size?
The environment is the ultimate cause of population stabilization. Two categories of factors are commonly used: physical environment and biological environment. Three subdivisions of the biological environment are competition, predation, and symbiosis.
Are population sizes stable?
Stable populations are theoretical models widely used by demographers to represent and understand the structure, growth and evolution of human populations. By definition, stable populations have age-specific fertility and mortality rates that remain constant over time.
What is the difference between a stable population and a stable age distribution?
What is the difference between a stable population and a stable age distribution? When the structure of a population is not changing over time, we say it has a stable age distribution. A cohort life table follows a group of individuals born at the same time from birth to the death of the last individual.
What does stationary population mean?
A population is considered stationary if the growth rate is zero and the age structure is constant. It thus follows that a population is considered non-stationary if either its growth rate is non-zero and/or its age structure is non-constant.
What causes population size to fluctuate?
Most major hypotheses link regular fluctuations in population size to factors that are dependent on the density of the population, such as the availability of food or the activities of specialized predators, whose numbers track the abundance of their prey through population highs and lows.
What is population growth explain factors responsible for fluctuating population density?
The density of a population in a given habitat during a given period, fluctuates due to changes in four basic processes, two of which (natality and immigration) contribute to an increase in population density and two (mortality and emigration) to a decrease.
What are the methods of estimating population size?
Ecologists often estimate the size and density of populations using quadrats and the mark-recapture method. A population can also be described in terms of the distribution, or dispersion, of the individuals that make it up. Individuals may be distributed in a uniform, random, or clumped pattern.
