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population cycle

In biology, regular fluctuations in the size of a population, as seen in lemmings, for example. Such cycles are often caused by density-dependent mortality: high mortality due to overcrowding causes a sudden decline in the population, which then gradually builds up again. Population cycles may also result from an interaction between a predator and its prey.

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São Tomé and Príncipe flag

São Tomé and Príncipe Flag
The stars stand for the two islands. Red recalls the struggle for independence. Yellow is said to represent the country's cocoa plantations. Effective date: 12 July 1975.

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