What are the three types of struggle for existence?

Explanation

**Step-by-Step Text Solution:**

1. **Identify the Concept**: The question asks about the three types of struggle for existence that organisms face.

2. **Define Intraspecific Struggle**: The first type is called intraspecific struggle, which refers to the competition among individuals of the same species for resources such as food, mates, and territory.

3. **Define Interspecific Struggle**: The second type is interspecific struggle, which involves competition between individuals of different species for similar resources, leading to interactions such as predation, competition, and symbiosis.

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