Ecologists sampled freshwater invertebrates at four ponds in disused gravel pits. Some freshwater invertebrates need high concentrations of dissolved oxygen. At each pond, the ecologists recorded the dissolved oxygen concentration and the number of invertebrate species found.
The results are shown in the table.
| Pond | Dissolved oxygen concentration in mg/L | Number of invertebrate species |
|---|---|---|
| A | 3.2 | 2 |
| B | 4.8 | 4 |
| C | 7.1 | 8 |
| D | 9.0 | 11 |
An ecologist claims that dissolved oxygen concentration alone determines how many invertebrate species are found in a pond. Evaluate this claim.
109 exam-style questions on OCR GCSE Biology 6.1 Monitoring and maintaining the environment, covering 6.1.1 Field investigation of distribution and abundance, 6.1.2 Human interactions and biodiversity, 6.1.3 Maintaining biodiversity, and 6.1.4 Environmental change and distribution of organisms. Each one has a worked solution and a mark scheme showing where the marks go.