Grey Thoughts
6.5.05
 
Evolution - The Phylogenic Tree Rots
Earlier, I posted on the supposed scientific progress made due to the Theory of Evolution. One of the claims made was "Data that reveals relationships among organisms" which closely relates to the claim that evolution is obvious because we can create a phylogenic tree relating all life and the claim that genetic analysis strongly supports the phylogenic tree.

A recent paper in Current Biology shows quite clearly that these claims are over-confident, uninformed or dishonest.

The traditional view of animal evolution is one of gradually increasing complexity.... This hierarchical view [of flatworms] was shaken in the mid 1990s by a phylogenetic study of small subunit ribosomal (r)RNA genes. This work elevated the acoelomate flatworms to a close relationship with the coelomate annelids and molluscs, in a group called the Lophotrochozoa, and pseudocoelomate nematodes moved close to the coelomate arthropods, creating a group called the Ecdysozoa.
Opposing the ‘new animal phylogeny’, as this new scheme has been called, are several analyses of huge numbers of genes – close to 800 in the most recent – sampled from the few animals with completely sequenced genomes: fruitfly, nematode and various vertebrates. These multigene analyses are unanimous in grouping coelomate arthropods and vertebrates to the exclusion of the pseudocoelomate nematodes, so reverting to traditional views of their relationships.
The overwhelming number of genes supporting the old scheme might suggest that the new animal phylogeny was finished – an artefact of a small data set. New work, however, suggests this conclusion is premature, and that the multigene result might itself be based on an artefact called long branch attraction

To unpack this, it is essentially saying that creating phylogenic trees is difficult and complex because some gene's indicate certain relationships and other gene's indicate different relationships.

A "Long Branch" is a term used when they decide that a species has evolved faster than other species. I.e. They assume evolution is true, and so when species A and species B do not fit their expected phylogenic tree, they assume that species Amust have evolved faster than species B because the genetic structures do not fit the normal pattern.

Long Branch attraction describes how using all methods of tree construction, long branched species tend to be grouped together as close relations
In common with previous studies Philippe et al. found that, using yeast as an outgroup, nematodes are located at the base of the tree with high statistical support. The flatworms are long branched too, and they are also found at the base of the tree. The change when short-branched Hydra is used instead of yeast is dramatic: both nematodes and flatworms jump up from the root of the tree to a position adjacent to the arthropods, strongly suggesting it was long branch attraction that placed them at the base.
But this result is troubling, as there is now an unexpected close association between nematodes – which, as presumed ecdysozoans are appropriately close to the arthropods – and flatworms which, according to the new animal phylogeny ought to be grouped with annelids and molluscs in the Lophotrochozoa

Yep. Even with all the wiggle room and ad hoc explanations, evolutionists are still having trouble making a phylogenic tree that fits the data. Next time some uninformed priest of evolution pushes the phylogenic tree line, point them to this article and see just how strong and blind their faith is...

(HT: Creation-Evolution Headlines)
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