An armchair tick from the new C&B

Subject: An armchair tick from the new C&B
From: Andrew Taylor <>
Date: Fri, 25 Jan 2008 12:58:46 +1100
On Fri, Jan 25, 2008 at 10:06:32AM +1100,  wrote:
> A phylogenetic tree may be constructed as a binary tree, but it
> isn't an arbitrary binary tree so the worst case scenarios for
> viable alternatives doesn't occur.

I was pointing how many taxonomic sequences are consistent with a
single phylogenetic tree.  The number of possible phylogentic tree is
larger still.  If my arithmetic is right there are 10^2212
possible phylogentic trees for Australia's 800 birds.  Checking these
tree one-by-one isn't feasible but as you say - you can look at subparts
of the tree and incremently build a tree  using on the evidence
we have.  But when even if you decide on a single tree, there are still
10^240 possible taxonomic sequences consistent with the tree.

So choosing a single atom from all 10^80 in the universe would be much
easier than what C&B have done.


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