Same answer chain

Use this to connect the question's starting point to the final result.

Use parent genotypes to identify possible gametes

Combine gametes to derive offspring genotypes

Map each offspring genotype to the affected or unaffected phenotype

State a probability that matches the derived offspring outcomes

Current question

Figure 3 shows one species of bird on a bird feeder. The birds use their beaks to reach nuts inside the bird feeder. Figure 4 shows the mean beak length of this species of bird in the UK. This species of bird often visits bird feeders.

Birds of this species are found in different parts of the world. Describe evidence that would show two individual birds are the same species.

Use after you understand the chain

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Show model answer Open mark checklist

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Why this earns marks

1 Use parent genotypes to identify possible gametes.
2 Combine gametes to derive offspring genotypes.
3 Map each offspring genotype to the affected or unaffected phenotype.
4 State a probability that matches the derived offspring outcomes.

Common weak answer: Names the topic but skips the middle reasoning links.