Reproductive isolation — Science definition
Any barrier — geographic, behavioral, temporal, or biological — that prevents two populations from interbreeding, allowing them to evolve independently.
Where it is taught
- Speciation & Mechanisms of Evolution — Evolution, Ancestry & Biodiversity, Life Science: Biology, Grade 10
In use
The key ingredient is reproductive isolation — some barrier that stops two groups from interbreeding.
Speciation & Mechanisms of Evolution
Questions using reproductive isolation
Problem 1
Explain why gene flow between two populations tends to work against speciation, while reproductive isolation allows it to happen.
Answer and explanation
Gene flow moves alleles between populations and keeps their gene pools mixed and similar, so they can't diverge into separate species. Reproductive isolation stops that exchange of genes, letting mutation, drift, and selection push each population's gene pool in its own direction until they become separate species.