These diagrams may or may not be accompanied by time scales. The time scales may or may not be linear. This type of diagram reflects the evolution relationships of organisms based on the distance from common ancestors. Again, they may or may not give an indication of time. Cladograms are often constructed on the basis of biochemical evidence, these days DNA homology is the most useful.
Cladograms take one of two forms, but each shows essentially the same information.
If you look closely you can see that they are sometimes similar to pedigree diagrams in construction. However the branches of a cladogram represents the development of a new species, not just a new generation. This more complex cladogram shows not only the relationships between bears, panda and dogs, but it gives an idea of time since these animals shared common ancestors. Time scales are often included on evolution diagrams. Take care with the interpretation of these.