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Re: Campbell's even crazier than a MANIAC? (archeopteryx



Michael Habib wrote:

<I'm glad that you brought this up - there is a common misconception
that galliforms and similar groundbirds are "poor" flyers. Galliforms,
in particular, are not "poor" flyers, but instead are burst
specialists. Galliforms fatigue rapidly in flight, an thus have poor
sustained flight ability, but that isn't the same as being bad at
flight. In fact, burst launching requires a range of highly derived
morphological traits. Tinamous do not have the burst power of
galliforms, but they are also short-ranged, acceleration specialists.
Not sure what the launch angle is on tinamous, but galliforms can
manage a nearly 90 degree launch angle.>

Perhaps you are right in this, but i think we can see it other way,
without the derogatory word "poor". It seems that galliforms and
tinamous share a short-range flight. Thus, we should hypothesize that
to be the basal condition based on parsimony alone (I'm basing this
reconstruction of basal character states in Livezey and Zusi, 2007).
The Galliformes may later get special adaptations while maintaining
the plesiomorphic short-range flight.

However, I know, Anseriformes, which seem to be the sister-group of
Galliformes, can engage in sustained flight, so the Galliform
short-range flight can be an apomorphic reversal. But, according to
the EPB, we should posit that sustained flight may be a sinapomorphy
of Neognathae (with an apomorphic reversal in galliforms), as only
short-range fliers or non-fliers are found basal to Neognathae (i.e.,
Palaeognathae). Alternatively, sustained flight should independently
appear in Anseriformes and the sister group of Galloanserae, which
however also indicates sustained flight has to be inferred as being
restricted to the Neognathae.

Reference:

Livezey, B. C. and Zusi, R. L. 2007. Higher-order phylogeny of modern
birds (Theropoda, Aves: Neornithes) based on comparative anatomy. II.
Analysis and discussion. Zoological Journal of the Linnean Society
149: 1–95.