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Question
Answer the following question.
"The size of a population for any species is not a static parameter." Justify the statement with specific reference to fluctuations in the population density of a region in a given period of time.
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Solution
The size of a population of any species is not a static parameter. It keeps changing in time, depending on various factors including food availability, predation pressures, and weather.
The population density in a given period can fluctuate due to the following four factors:
- Natality: It refers to the number of births during a given period in the population that are added to the initial density.
- Mortality: It refers to the number of deaths during a given period that reduced the size.
- Immigration: It is the number of individuals of the same species that have come into the habitat from elsewhere during the given period.
- Emigration: It is the number of individuals who left the habitat and have gone elsewhere.
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