What is the difference between primary succession an secondary succession

Primary succession occurs following an opening of a pristine habitat, for example, a lava flow, an area left from retreated glacier, or abandoned strip mine.

In contrast, secondary succession is a response to a disturbance, for example, forest fire, tsunami, flood, or an abandoned field.

because they are eaten by the frog and the frog getseaten by the snake and the snake by the eagle

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