They use people.
It is true that scientists determine evolutionary relationships by looking at breeding behavior, geological distribution, and structural similarities between organisms. Scientists can use other criteria to determine evolutionary relationships.
so they can find out which organism is which (identify organisms.)
behavior, embryology, and DNA.
They see similarities with structures between modern day organisms and older organisms.
They are classified according to the DNA they share with other organisms.
Scientists classify organisms by the dichotomous key. They classify by looking at if it moves or not, then they look at characteristics, then they can see what they are.
Organisms that are closely related usually have very similar chromosomes numbers and a large degree of homology (similarity) beween their chromosomes (but the chromosomes are different enough to maintain genetic isolation).
scientists use taxonomy to classify and separate them into different groups
Scientists refer to organisms by using bynomial nomiclature also known as "King Phillip Came Over For Ginger Snaps"
either one of these...a diagram showing how scientists think different groups of organisms are related.b.A branching tree is a diagram that shows how scientists think different groups of organisms are related. It is a metaphor used to describe the relationships between organisms, both living and extinct. Its use dates back to at least the early 1800s.