I just can’t help it. Not even PZ Meyers over at Pharyngula has posted this one yet! Although he’d be able to explain the science better then I can, I want to beat this guy to the punch.

It seems the IDers are going to have to find a new example for their supposed ‘irreducible complexity’ rants and raves. For quite awhile now the structure and function of the bacterial flagellum has been the poster ‘child’ for irreducibly complex structures. That is, a structure that could not have evolved part by part. It is argued that the flagellum only function as a whole. Its individual parts or subgroups are outside the realm of natural selection – they had no function. Without function, it is argued, they could not have been selected for during evolution. We’ve know for awhile that some of the motors in the flagellum are used elsewhere but this new research suggest quite a bit more.

It seems that 50 genes are responsible for controlling the building and operation of a flagellum. This study shows that 24 of these genes are highly conserved between bacterial species harbouring flagellum and have arisen through successive duplications throughout evolutionary history. Working in reverse, they most likely arose from a single ancestral gene via duplication. The scientists I read are able to show the actual phylogenetic development of the successive duplications and how they occurred lock step with the assembly of the flagellar structures.

I’m not surprised by this research. I try to repeat a simple theme to my AP biology students. Duplication, redundancy, specialization – over and over!! We see it from endosymbiotic theory (redundancy in vesicles), to organism segmentation, to genes. The question I’m asking is, what will IDers use/say about this? I KNOW it will be spun by the discovery institute [DI]. I should link them but I cannot force myself to make it easier for you to find that FUD (fear, uncertainty, doubt).

As a note, I really like PZ’s blog. Its informative about evolutionary developmental biology and attacks IDers rabidly. I’m not sure his style, not quite as venomous as Dr. Dawkins, moves us forward but you’ll be hard pressed to find a site that makes evolutionary developmental genetics, like Hox genes, more accessible to the population.

Linzel

P.S. You think PZ would grace me with a comment? And let me know if you think anything I’ve posted if inaccurate – or if you can increase my accuracy.

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