A study of three living alpine gentian species produced an evolutionary tree. In the tree, the branch leading to species M diverges from the lineage leading to N and O 15 million years ago. The lineages leading to N and O diverge from each other 6 million years ago.
What does the tree show about M?
M is more closely related to O because M and O diverged from each other 6 million years ago.
M is equally closely related to N and O because their lineages meet M's at the same branching point.
M is more closely related to N because N and M share an ancestor more recently than O and M.
M is an ancestor of N and O because its lineage diverges before theirs.
81 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.