Fossils in three undisturbed rock layers have the following features.
Table
| Rock layer | Age / million years | Typical number of toes |
|---|---|---|
| Lowest | 50 | 4 |
| Middle | 30 | 3 |
| Highest | 10 | 1 |
Which conclusion is supported without assuming that every fossil is a direct ancestor of the next?
Toe number decreased over time, although the fossils alone cannot establish direct ancestry.
Toe number increased over time, although the fossils alone cannot establish direct ancestry.
Toe number decreased over time, so each fossil must represent the next direct ancestor.
Toe number increased over time, so each fossil must represent the next direct ancestor.
37 exam-style questions on AQA GCSE Biology 6.3 The development of understanding of genetics and evolution, covering 6.3.1 Theory of evolution, 6.3.2 Speciation, 6.3.3 The understanding of genetics, 6.3.4 Evidence for evolution, 6.3.5 Fossils, 6.3.6 Extinction, and 6.3.7 Resistant bacteria. Each one has a worked solution and a mark scheme showing where the marks go.