IB skill practice

Analyse molecular evolution and phylogenetics

Paper 1, Paper 2 5 marks Difficulty 5

Distinguish homologous and analogous evidence

A comparison in a Melbourne HL genetics workshop shows two vertebrate forelimbs with the same bone arrangement but different functions. Explain why this is evidence for common ancestry. Use the diagram labels, data values, or inheritance pattern before writing the answer. 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.