Is all structure in food webs phylogenetic? Phylogenetic Correlations (III)

Dear List Members,

in a paper published last year, Williams and Martinez
[http://www.foodwebs.org/index_page/Williams2008JAE.pdf] put the
single "'niche dimension'" of their classical niche model
[http://www.foodwebs.org/index_page/Williams2000Nature.pdf] into
apostrophes, and explained that the model would actually "simulate
[...]  phylogenetic aspects" of food-web structure.  I agree (see
http://axel.rossberg.net/paper/Rossberg2006a.pdf).

The argument by which they arrive at this conclusion is as follows:
related species can have high trophic similarity, the niche model
produces species pairs with high trophic similarity, and therefore the
niche model simulates phylogenetic aspects.  Obviously, this argument
is stringent only when phylogenetic correlations are not only
contributing to, but the dominating cause for high trophic similarity
between species pairs (otherwise, high trophic similarity in the niche
model could reflect other structuring mechanisms).

This is the third part of a tutorial on phylogenetic correlations in
food-webs.  Here, I investigate how far this kind of reasoning can be
taken.  That is, I discuss the question how much of the structure we
see in food webs (all of it?) can be explained phylogenetically.

For parts I and II of the tutorial, please see

 http://permalink.gmane.org/gmane.science.biology.foodwebs/31


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