RSS 2.0 Feed

» Welcome Guest Log In :: Register

    
  Topic: Incongruence in phylogenetic trees, post and ref archive< Next Oldest | Next Newest >  
niiicholas



Posts: 319
Joined: May 2002

(Permalink) Posted: Jan. 18 2003,23:54   

I noticed Charlesbois's article also, comments are here:

Re-evolution of complex characters

IMO this quote is the key one for putting some balance into discussions where Woese, Doolittle, etc. are cited:

Quote

We and others have been exploring 'whole-genome trees' as a means of overcoming the noise and bias of single-protein analyses, to extract the bulk phylogenetic signals that are inherent in genomes. The input data for genome trees can be the proportions of genes or proteins that genomes hold in common, or (as we prefer) the mean pairwise similarities between shared proteins. Despite some early indications to the contrary, whole-genome trees have now largely converged on the rRNA-sequence tree.

For us as, presumably, for the verticalists this convergence means that lateral gene transfer has not undermined descent with modification as the default explanation for microbial biodiversity, nor (as recently suggested by Ford Doolittle) has it thrown microbial classification into disarray. Lateral transfer is not both quantitatively important and directional. One of the few widely accepted instances of lateral gene transfer the origin of chloroplasts from relatives of cyanobacteria is clearly visible in our whole-genome trees, and even more so in 'sub-genome trees' based on functional subsets of genomes.


nic

Edited by niiicholas on Jan. 18 2003,23:54

  
  3 replies since Dec. 23 2002,23:39 < Next Oldest | Next Newest >  

    


Track this topic Email this topic Print this topic

[ Read the Board Rules ] | [Useful Links] | [Evolving Designs]