Why is preservation of wild varieties of plants and animals necessary?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Importance of Wild Varieties:**
- Wild varieties of plants and animals are crucial for biodiversity. They contribute to the overall health of ecosystems and play a vital role in maintaining ecological balance.

2. **Gene Banks for New Varieties:**
- Wild varieties serve as gene banks. They provide genetic material that can be used to breed new varieties of plants and animals. This is essential for agricultural development and improving food security.

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