Scientists recorded the species living in two green-roof ecosystems. The same species of moss grew on both roofs.
The table shows the results.
| Green roof | Number of plant species | Number of animal species | Number of microorganism species | Number of animal species using the moss for food or shelter |
|---|---|---|---|---|
| R | 8 | 6 | 4 | 3 |
| S | 18 | 20 | 12 | 4 |
During a long period of dry weather, the population of the moss declined sharply on both roofs.
Calculate the percentage of animal species that used the moss for food or shelter on each green roof.
Using the data and your answer to part (a), explain which green-roof ecosystem is likely to remain more stable after the moss population declines.
84 exam-style questions on AQA GCSE Biology 7.3 Biodiversity and the effect of human interaction on ecosystems, covering 7.3.1 Biodiversity, 7.3.2 Waste management, 7.3.3 Land use, 7.3.4 Deforestation, 7.3.5 Global warming, and 7.3.6 Maintaining biodiversity. Each one has a worked solution and a mark scheme showing where the marks go.