Final answer:
Phylogenetic trees and cladograms are the diagrams used to show evolutionary relationships between organisms, with each representing a hypothesis of evolutionary connections based on genetic and physical similarities and differences.
Step-by-step explanation:
The diagrams we use to show evolutionary relationships are known by two names: phylogenetic trees and cladograms. These graphical representations serve as models to depict the evolutionary history of organisms and are used by scientists to hypothesize how different species are related based on evidence such as genetic and physical traits. A phylogenetic tree consists of branches and nodes, with each node representing a common ancestor from which two new species diverged. Cladograms are similar visual tools that show relationships between organisms based on shared characteristics.