Swallows fly from the UK to southern Africa each autumn and return each spring. Which type of environmental change causes this change in distribution?
A geographic change in the distance between the two continents
A change caused by human interaction with the birds' habitat
A seasonal change in temperature and in the supply of insects
A genetic change in the alleles carried by the swallow population
38 exam-style questions on AQA GCSE Biology 7.2 Organisation of an ecosystem, covering 7.2.1 Levels of organisation, 7.2.2 How materials are cycled, 7.2.3 Decomposition, and 7.2.4 Impact of environmental change (HT only). Each one has a worked solution and a mark scheme showing where the marks go.