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SABiologyQuick questions

Topic 4: Evolution

Quick questions on Genetic drift and gene flow (SACE Stage 2 Biology)

1short Q&A pairs drawn directly from our worked dot-point answer. For full context and worked exam questions, read the parent dot-point page.

What is a small founding group?
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Because only a few birds founded the island population, they carry just a small, random sample of the mainland gene pool. By chance, some alleles common on the mainland may be rare or absent on the island, and some rare alleles may be over-represented. So the island population's allele frequencies differ from the mainland's right from the start - the founder effect - even before any natural selection acts.

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