Tuesday, February 8, 2011

Analyzing the three major branches

Working with the idea that very early on, three major branches of birds formed (water birds, shorebirds, and land birds), we can look at the landbirds.
As we have seen the chart shows them as green.
But we can also see that the birds in brown are a subgroup of the landbird major branch.
So we see landbird subgroups in green and others in brown.
Turning to the birds in red, we note that they are in two distinct groups labeled Anseriformes and Galliformes. The Anseriformes are clearly waterbirds and the Galliformes are secondarily weak-flying landbirds.
Also, including the purple group, we see that they are secondarily flightless landbirds. So we can add them to the summary:

landbirds - green, brown, red (Galliformes), purple (Ratites)
shorebirds - gold (Charadriiformes/Charadrii)
waterbirds - blue, gold (Charadriiformes/Lari), red (Anseriformes)

All that is left are the grey and black groups, which as we have seen are still unsettled. So their lineages are unclear, but in time may become clearer. .
Everything we have seen, that is clear, supports the idea of a very early divergence into the three major branches, with subbranches stemming from each major branch.

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