The scientists arranged the branches into groups made up of one ancestral variant and all of its descendant, mutated variants. they are color-coded in the tree. do all of the groups have the same number of branches or branch tips? what does this result indicate?

The evolutionary tree is used by the scientists to explain the evolutionary relationship between the organisms. The tree is prepared on the basis of molecular evidence and phylogeny relationships.

The same number of branches is not present in all groups. This might occur become some groups has high mutation rate than the other groups. This results shows that the different groups has accumulated the different types of mutation under the specified period of time.    

ya the other dude is right