Two scientists disagree about how a group of extinct reptiles should be classified. Scientist 1 uses the shape of the fossil bones. Scientist 2 wants to use DNA taken from the fossils.
Give one reason why DNA evidence is usually more reliable than evidence from the shape of bones.
Suggest two reasons why scientist 2 will not be able to use DNA evidence for most extinct species.
Explain why the fossil record does not give a complete evolutionary tree for these reptiles.
Suggest why the two scientists may still classify the reptiles differently even when they use the same fossils.
40 exam-style questions on AQA GCSE Biology 6.4 Classification of living organisms, covering 6.4 Classification of living organisms. Each one has a worked solution and a mark scheme showing where the marks go.