[R] Mixed effects model with a phylogenetic tree/ distance matrix as a random effect

[Roey Angel]

Hi,
I'm trying to build a mixed-effects model in which I'd like to include 
either a distance matrix or a phylogenetic tree as a random effect.
The troubles I've had are that:
1. Function lmer() in package lme4 only accepts a data frame column as a 
random factor and not a distance matrix.
2. Function MCMCglmm() in package MCMCglmm only accepts a rooted and 
ultrametric phylogenetic tree as a pedigree argument while my tree is 
neither (and for various reasons I cannot construct one or coerce mine 
to be a rooted, ultrametric tree).

Is there any way around it?
I'd appreciate mostly a solution to problem 1.

Roey

-- 
Dr. Roey Angel

Max-Planck-Institute for Terrestrial Microbiology
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