Who said they haven’t changed in millions of years. They may be similar, but we see a lot of speciation within all the groups that you describe. There may have been birds (for example) millions of years ago, but we are seeing countless more variants evolved now than we are aware of that existed millions of years ago.
So, basically you are saying that your family tree is a record of evolution and each individual on it (ancestors and descendants) are sub-species of humans? That does put a new twist on things. That would equate to about 6.8 billion human sub-species now living and a total of over 15 billion since time began? If we evolved from apes, why are each line of apes not evolving still?