A mole uses its forelimbs to dig and an otter uses its forelimbs to swim. Each forelimb contains one upper bone, two lower bones, a group of wrist bones and five digits, arranged in the same order. Which statement about the forelimbs of these two animals is correct?
They are homologous structures with the same basic structural origin.
They show that moles and otters belong to the same species.
They have separate structural origins because they are used for different functions.
They show that moles and otters have faced the same selection pressures.
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.