Final answer:
Taxonomists group organisms based on similar DNA sequences, focusing on homologous structures and genes to determine evolutionary relationships and construct a phylogenetic hierarchy.
Step-by-step explanation:
Taxonomists today tend to group organisms into the same category based on similar DNA sequences. This approach stems from a desire to make evolutionary connections among organisms using both morphologic (form and function) and genetic evidence. Homologous structures are physical features that imply a shared evolutionary history, providing insights into their phylogeny. The bones in the wings of bats and birds serve as an example of homologous structures, showcasing that these organisms may have evolved from a common ancestor. Taxonomy today relies on morphologic and molecular data to organize living organisms. Phylogenetic classification uses a hierarchical model based on evolutionary relationships determined by homologous characteristics and genes.