A population of seed-eating mice has inherited variation in jaw muscle size. A long dry period leaves mainly large, hard seeds as food. Several generations later, the allele associated with larger jaw muscles is more common in the population.
Which statement describes how the allele for larger jaw muscles became more common?
Mice with larger jaw muscles survived longer, but both jaw types produced the same number of offspring.
Both jaw types obtained enough food, so the two alleles were passed to offspring at the same rate.
The mouse population increased in size, so the larger-jaw allele automatically formed a greater proportion of its alleles.
Mice with larger jaw muscles obtained more food, so they produced more offspring that inherited the allele.
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.