4. Is predation a density-dependent or density-independent factor?

The correct answer is density-dependent factor.

Explanation:

The factors whose influences on the growth or size of the population changes with the density of the population are known as the density-dependent factors. The availability of food, disease, predation, and migration are some types of density-dependent limiting factors.  

One of the density-dependent factors in nature is predation, predation confines various populations. The population of the prey and the predator encircle towards each other, with the population of the predator somewhat lagging behind the population of the prey.  

With the increase in the population of the prey, the predator gets more to eat, and thus the population of the predator increases. With the increase in the predator population, pressure imparts on the prey population and it starts to decline. The decline in the availability of the food eventually makes the population of the predator to decline. Therefore, it can be seen that both the population of the prey and the predator are affected by predation, that is, a density-dependent factor.  

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