Practice question

Allopatric speciation occurs when geographic barrier such as mountain range, river or canyon splits population preventing gene flow, allowing independent accumulation of mutations, drift and local adaptation. Over time reproductive isolation evolves via Dobzhansky-Muller incompatibilities. Grand Canyon squirrels and Darwin's finches illustrate. Geographic isolation is primary requirement, contrasting with sympatric mode. Hence Geographic isolation is essential condition initiating allopatric divergence and biodiversity. This concept integrates genetics, ecology and molecular evidence, frequently tested in NEET, GATE and CSIR-NET, highlighting links between genotype, phenotype and environment.