# A population of moths lives in a woodland area. Some moths have a pale wing colour and some have a dark wing colour. Over several generations, the proportion of dark-winged moths in the population increases. Explain how natural selection could account for this change in the population of moths.

> WJEC GCSE Biology (Wales) — 2.4.2 Evolution and natural selection · Explain · 4 marks

## Mark scheme (4 marks)

1. There is variation in wing colour within the moth population (pale and dark)
2. Dark wing colour is an advantageous phenotype / dark-winged moths are better suited to the environment (e.g. better camouflaged from predators)
3. Dark-winged moths are more likely to survive and reproduce, passing the advantageous allele on to offspring
4. Over many generations, the frequency of the advantageous allele (dark wing colour) increases in the population

## Key terms

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

## Related

- [Revision notes for WJEC GCSE Biology (Wales)](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/a-population-of-moths-lives-in-af895a06) · Published by Druglandscape Ltd.