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The population of an insect species shows an explosive increase in numbers during rainy season followed by its disappearance at the end of the season. What does this show ?
The food plants mature and die at the end of the rainy season.
Its population growth curve is of $J$-type.
The population of its predators increases enormously
$S$-shaped or sigmoid growth of this insect
Solution
(b) : $J$-shape of growth pattern can be easily observed in algae blooms, some insects, annual plants and the lemmings of Tundra. In the beginning density of the population increases rapidly in compound interest fashion and then stops abruptly as the environmental resistance or other limiting factors become effective. These factors may be food, space, seasonal (frost, excessive rain etc.) or the termination of reproduction session.