IB Biology SL A4.1.7 Reproductive isolation & differential selection
IB Biology SL A4.1.7 Reproductive isolation & differential selection

IB Biology syllabusFirst assessment 2025
Practise how reproductive isolation and different selection pressures can separate gene pools and lead populations towards speciation.
How this is tested
- explain how geographical, temporal or behavioural barriers prevent gene flow
- link different environments to selection for different traits in separated populations
- interpret data on breeding, barriers or trait distributions to support speciation claims
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