# Explain why fossils are important as evidence for the theory of evolution by natural selection. Include in your answer a reason why the fossil record is incomplete.

> AQA GCSE Biology (8461) — 4.6.3 The development of understanding of genetics and evolution · Explain · 4 marks

## Mark scheme (4 marks)

1. Fossils show the remains of organisms that lived millions of years ago
2. Fossils show how organisms have changed / evolved over time
3. Many organisms did not form fossils because soft-bodied organisms decay completely / do not leave hard remains
4. Because the fossil record is incomplete, it is difficult to trace the full evolutionary history of all species / some transitional forms are missing

## Key terms

- [fossil](https://www.gradenine.co.uk/glossary/fossil)
- [evolution](https://www.gradenine.co.uk/glossary/evolution)
- [natural selection](https://www.gradenine.co.uk/glossary/natural-selection)
- [fossil record](https://www.gradenine.co.uk/glossary/fossil-record)

## Related

- [Revision notes for AQA GCSE Biology (8461)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-why-fossils-are-important-as-5a02608d) · Published by Druglandscape Ltd.