IB skill practice

Evaluate ecology, conservation, and ecosystem change

Paper 1, Paper 2 5 marks Difficulty 5

Evaluate trophic cascade

A food-web study in a Auckland HL data-response class shows predator removal followed by herbivore increase and plant biomass decline. Explain the ecosystem change. Enter the answer and choose the interpretation that best matches the HL Biology evidence.

Worked practice: biological evidence and answer

Use the labelled biological evidence first, then connect it to the final answer.