The scientist believe that evolution is gradual. But extinction, part of evolutinary story, are ' sudden ' and 'abrupt' and also group-specific. Comment whether a natural disaster can be the cause for extinction of species.

Explanation

**Step-by-Step Solution:**

1. **Understanding Evolution and Extinction**:
- Evolution is generally a gradual process where species change over time through natural selection and adaptation. In contrast, extinction can occur suddenly and is often specific to certain groups of organisms.

2. **Definition of Extinction**:
- Extinction refers to the complete disappearance of a species from Earth. When a species is extinct, it means that there are no living individuals left.

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