Phylogeny is the study of the evolutionary history and relationships among different species or groups of organisms. It often involves constructing a phylogenetic tree, which visually represents these relationships based on shared characteristics and genetic information. This helps scientists understand how species have evolved over time and how they are related to one another. By analyzing traits and genetic data, researchers can trace the lineage of organisms back to common ancestors. This process is essential for fields like taxonomy, which classifies living things, and conservation biology, which aims to protect biodiversity by understanding evolutionary connections.