Answer:
Advances in the study of phylogeny led to a classification system based on evolutionary relationships. This new system is based on the concept of a clade which contains a single common ancestor that all species within that clade descended from.
Step-by-step explanation:
After Darwin's evolutionary studies, the scientists looked for a way to classify organisms on the basis of phylogeny. A phylogeny depicts the relationship between organisms based on the common ancestors that they might have. A phylogeny can be shown in a diagram like a cladogram. This diagram shows branches known as clade for each particular organism that might have evolved from a particular common ancestor.