Phylogenetics is the study of the evolutionary history and relationships among different groups of organisms. It uses various methods, such as molecular sequences, morphological traits, and fossils, to infer the patterns of descent and divergence among taxa. Phylogenetic trees are graphical representations of these relationships, showing the branching order and relative time of speciation events. Phylogenetics has many applications in biology, such as understanding the origin and diversity of life, reconstructing the ancestral features of organisms, and testing hypotheses about adaptation and coevolution.