We have seen that the Senter scatterplot completely contradicts the standard dinosaur to bird idea. The supposed path from dino to bird wanders all over the place between unconnected groups.
So how does the scatterplot relate to the ideas that I have been presenting?
First we would remove the Tyrannosaur cluster since it is not related at all to the origin and development of birds. We are left with the "Birdlike cluster" and an assortment of other unconnected groups.
According to the hypothesis I have been presenting, the Birdlike cluster developed from the pterosaurs, which unfortunately are not shown on the chart. So we cannot analyze that aspect of the subject.
But we can consider the relationship of the Birdlike Cluster to the other groups such as the Oviraptors, Alvarezsaurids, Therizonosaurids etc.
What I have been presenting is the idea that these groups developed from the flying birds within the Birdlike cluster. They are SECONDARILY flightless.
The reason that they appear morphologically unconnected in terms of the scatterplot is that they are as different as flightless birds are from flying birds. And there is no way in practice to distinguish intermediates because if a bird fossil is found - it is identified as either one or the other.
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