What is the estimated number of species present on the earth?

Explanation

### Step-by-Step Solution:

1. **Understanding Species**: Begin by defining what a species is. A species is a group of organisms that are similar and can breed to produce fertile offspring. This concept helps us understand biodiversity.

2. **Estimating Total Species**: Scientists have conducted research to estimate the total number of species present on Earth. This includes both plants and animals.

3. **Current Estimates**: According to the latest scientific data, the estimated number of species on Earth is approximately 8.7 million. This figure encompasses a wide variety of organisms, including those that are yet to be discovered.

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