Geographical isolation is important in assisting the process of A - VCE - SSCE Biology - Question 16 - 2003 - Paper 1

Geographical isolation plays a crucial role in the process of speciation by preventing gene flow between populations. When a population is divided by geographical barriers such as mountains, rivers, or distances, the separated groups can evolve independently. This independent evolution can lead to the development of distinct species.

In contrast, adaptation relates to how organisms adjust to their environments, and gene flow refers to the transfer of genetic material between populations, which would be reduced by geographical barriers. Fossilisation is a process entirely separate from the reproductive isolation required for speciation.