Because if we only classify animals by morphology, many animals have the same describable traits and physical structures. Genes helped taxonomy better classify and aggregate animals. Molecular genetics is scientific study of composition of genes. This field is a subcategory of biology and heredity which is responsible for unearthing and delving the anatomy and physiology of the genes. This field helps us to understand and find evidence in the compounds, substances and elements found and synthesized in our genes and what contains in our nucleic acides –RNA and DNA –framework of our chromosomes. And also the origin and history of how genes came to be. These are codes and like-signals that makes us who we are in a macro-perspective.
There is a common misconception that traditional taxonomy is based on morphology, while cladistics is based on genetic data. How is this misconception incorrect?