Evolution of complexity in a parasite

A nematode that parasitizes May beetles, potato beetles, and dung beetles has proven to have more genes than the model organism/nematode Caenorhabditis elegans.  This is an interesting development, given that so many parasites end up with a reduced number of genes, as their hosts supply many functions and substances that a parasite can simply take in, rather than expending the energy to make them.  A nematode parasitizing humans exhibits the commonly expected gene reduction.

The great number of toxins the beetles produce is thought to be the reason for Pristionchus pacificus‘s relatively large number of genes.  Here is the most data-rich paragraph from the article:

The sequencing of the genome of Pristionchus pacificus has now confirmed this suspicion: the genome, consisting of around 170 megabases, contains more than 23,500 protein-coding genes. By comparison, the model organism of Caenorhabditis elegans and the human parasite Brugia malayi (whose genome was sequenced in 2007) only have about 20,000 or 12,000 protein-coding genes, respectively. “The increase in Pristionchus is partly attributable to gene duplications,” explained Ralf Sommer. “These include a number of genes that could be helpful for breaking down harmful substances and for survival in the complex beetle ecosystem.”  Source

In addition, here is another example of how gene duplications have been instrumental in the evolution of complexity, something that Behe denies on the basis of one example of a yeast species in Edge of Evolution.  He certainly fails to understand science and, oh, logic, sense, reasoning ability, or anyhow he makes an exceedingly great facsimile of intellectual failure in his books.

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