What is meant by the term extinction ?

Explanation

**Step-by-Step Solution:**

1. **Definition of Extinction**: Extinction refers to the process through which a species, family, or group of organisms ceases to exist. This means that there are no living members of that species left on Earth.

2. **Understanding Extant**: The term "extant" is used to describe species or groups that are still in existence. In contrast, when a species is extinct, it means that it is no longer extant.

3. **Causes of Extinction**: Extinction can occur due to various factors, including environmental changes, loss of habitat, climate change, human activities, or competition with other species.

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