During 1912–1923, biogeography shifted toward landscape-scale analysis, revealing how elevational zonation, habitat heterogeneity, and landscape connectivity shape species distributions across regions. Researchers integrated ecological, geographic, and stratigraphic perspectives to uncover patterns of distribution that transcend local communities and to lay groundwork for macroecology and island-like dynamics. Historical Significance: The period's work established core paradigms that link habitat structure to biogeographic patterns, unified montane and continental biogeography, and foreshadowed cross-regional faunal correlations and the emergence of species–area concepts that would guide future conservation and biodiversity studies.