A population of frogs has inherited variation in tolerance to low temperatures. After winters became colder, scientists recorded the percentage of frogs with low-temperature tolerance.
| Generation | Percentage of frogs with low-temperature tolerance |
|---|---|
| 0 | 18% |
| 5 | 35% |
| 10 | 57% |
| 15 | 74% |
The winters remain cold.
Explain the change shown in the table and predict what is likely to happen to the percentage in later generations.
85 exam-style questions on Edexcel GCSE Biology 4.1 Evolution and natural selection, covering 4.1.1 Work of Darwin and Wallace and 4.1.2 Resistant organisms and evolution. Each one has a worked solution and a mark scheme showing where the marks go.