Abstract

Understanding the distribution of life on Earth remains a central challenge in biodiversity science, with implications for conservation in an era of rapid global change. This review synthesizes current knowledge on global patterns of insect and animal diversity, examining the ecological drivers, biogeographical mechanisms, and conservation challenges shaping contemporary biodiversity distributions. The latitudinal diversity gradient—increasing species richness toward the tropics—represents a pervasive macroecological pattern, although emerging evidence suggests that small-bodied invertebrate taxa may exhibit weaker or even inverse gradients, challenging long-held generalizations. Topographic heterogeneity and climatic stability interact to generate pronounced altitudinal gradients and concentrations of endemism, particularly in tropical montane systems that function as both biodiversity cradles and museums. Ecological drivers including climate energy, productivity, habitat heterogeneity, and disturbance regimes operate across scales to regulate species richness, while evolutionary processes—speciation, extinction, and dispersal—determine the biogeographic imprint visible today. Anthropogenic pressures, particularly land-use change, climate change, invasive species, and pollution, are driving unprecedented biodiversity loss, with insects experiencing substantial but poorly documented declines. International policy frameworks, including the Kunming-Montreal Global Biodiversity Framework, provide mechanisms for coordinated conservation action, yet transformative change in biodiversity governance remains urgently needed. This review identifies critical knowledge gaps, particularly regarding insect diversity in tropical systems, and emphasizes the need for integrated approaches combining remote sensing, biodiversity modeling, and community-based monitoring to inform effective conservation strategies.