Blue tits feed on both aphids and caterpillars in a local woodland. An insecticide was sprayed to control the aphids.
| Organism | Number | Mean biomass of each organism (g) | Biomass of population (g) |
|---|---|---|---|
| Oak trees (leaves) | 12 | 18,000 | 216,000 |
| Caterpillars | 450 | 0.5 | ? |
| Aphids | 9,000 | 0.003 | 27 |
| Blue tits | 15 | 11.5 | 172.5 |
Explain how killing the aphids would affect the population of caterpillars in this woodland.
