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RATITES AND BROODING



"Matthew Troutman" <m_troutman@hotmail.com> sent this to me alone.  However,
that was an accident, since he wanted to post it to the whole of the list.
At his request, then, here are some more details concerning brooding
distribution as mapped onto a variety of different bird phylogenies:

>Tom Holtz wrote:
>
><<Might I suggest that you actually employ the appropriate test for 
>this? That is, map this trait on a bird phylogeny (or multiple bird 
>phylogenies) and find out its distribution? That way you can find out if 
>it is basal for Neornithes, at least.>>
>
>What avian phylogenies?  :-)
>
>Seriously though, there aren't really that many acceptable avian 
>phylogenies available for scruntiny that are 1) widely accepted; 2) have 
>not been shown to be totally wacko; 3) look good but there are better 
>ones out there.  I personally don't know whether or not brooding is 
>plesiomorphic for Neornithes because ratites and tinamous have a weird 
>male parental care system not really found in any other avian orders.
>
>Hopp lists in another post the various birds that he found photos on 
>with the theropod brooding style: flamingos, ratites, ducks and ?gulls 
>all are relatively colonial birds with the exception of ratites.  
>Ratites are problematic because of the male parental care system and the 
>others are possibly closely related.  
>
>For one, Per Ericson argues that the avian orders Charadriiformes 
>(shorebirds, gulls), Ciconiiformes (storks, ibies, and possibly 
>flamingos) and Anseriformes (ducks) are all closely related.  The 
>brooding seen in these birds could just be a plesiomorphic feature of 
>these three groups.  
>
>For another, phylogenies by Cracraft show that anseriforms are related 
>to galliforms (fowl; whose brooding habits do not show much parental 
>care) but that ciconiiforms and charadriiforms are related.  (One note: 
>flamingos as I, Darren, and Ron have pointed out many times on this list 
>are possibly related to the recurvirostrid shorebirds.)  
>
>And moreover, Brad Livezey believes that anseriforms and galliforms are 
>related but expresses doubt (but not complete denial) on the 
>relationship of charadriiforms and ciconiiforms.
>
>Storrs Olson and Alan Feduccia believe that the anseriforms are related 
>to charadriiforms and that ciconiiforms are polyphyletic with herons 
>being close to gruiforms (cranes), ibies being close to gruiforms and 
>charadriiforms, and storks being related to New World vultures.  
>
>Avian phylogenies provide ambiguous support for plesiomorphy of brooding 
>behavior in neornthines.  As I pointed out above, most of these birds 
>are highly colonial and that may have something to do with sheltering.  
>Obviously, we need more evidence.
>
>Matt Troutman 
>m_troutman@hotmail.com
>
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Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:tholtz@geol.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661