A researcher studied variation in adult height. The people in each pair were the same age and sex. Identical twins have the same genome.
| Pairs compared | Mean difference in adult height in cm |
|---|---|
| Identical twins raised in different homes | 4.6 |
| Unrelated people raised in the same home from birth | 7.8 |
What do the results suggest about the causes of variation in adult height? Explain your answer.
80 exam-style questions on AQA GCSE Biology 6.2 Variation and evolution, covering 6.2.1 Variation, 6.2.2 Evolution, 6.2.3 Selective breeding, 6.2.4 Genetic engineering, and 6.2.5 Cloning. Each one has a worked solution and a mark scheme showing where the marks go.