Practice IB Biology Topic A4.1 Evolution and Speciation with authentic exam-style questions for both SL and HL students. This question bank focuses on the exact syllabus content for A4.1 Evolution and Speciation and mirrors Paper 1A, 1B, 2 style where relevant.
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The diagram shows forelimbs adapted for different movements. Which interpretation is best supported by their bone arrangement?
What happens to global species diversity during a speciation event?
DNA sequencing reveals a 98.8% similarity in gene sequences between humans and chimpanzees.
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Species P and R share a similar body form. Which relationship is most strongly supported?
| Species pair | Differences among homologous DNA sites |
|---|---|
| P–Q | 4 |
| P–R | 18 |
| Q–R | 17 |
Which process contributed to the divergence of bonobos and common chimpanzees?
Analogous; similar selection produced the same bone sequence
Homologous; shared bone topology supports common ancestry
Vestigial; reduced bones show loss of limb function
Artificially selected; humans fixed the different proportions
It decreases, because one species becomes extinct
It remains the same, as one species is replaced by another
It increases, due to the formation of two or more new species
It fluctuates randomly due to genetic drift
P and R; similar morphology is more objective evidence
P and R; more differences indicate recent divergence
Q and R; their site differences are intermediate
P and Q; fewer differences indicate recent common ancestry
Artificial selection
Interspecific hybridization
Geographic isolation caused by a river
Convergent evolution in similar environments
