Why are geographical barriers significant in population biology?

Geographical barriers are significant in population biology because they prevent gene flow between populations. When a physical barrier, such as a mountain range, river, or ocean, exists, it restricts the movement of individuals from one population to another. This limitation on interaction means that distinct populations can evolve independently over time, leading to the development of unique genetic traits as they adapt to their respective environments.

As gene flow decreases, populations may experience different selective pressures based on their specific habitats. This process can enhance the likelihood of speciation, where one population evolves into a separate species. The genetic differences can accumulate over generations due to mutation, natural selection, and genetic drift. The absence of gene flow reinforces the divergence and adaptation of populations to their local environments.

Understanding the role of geographical barriers is crucial for studying biodiversity, conservation efforts, and predicting the outcomes of environmental changes on species distribution and evolution.