May 06, 2011

NEWS: Insect Has Third Pair of 'Wings'

I found this recent news article quite funny and interesting:
In 250 million years of insect evolution, the appearance of new wings is unprecedented. Transformations and losses of wings, yes, but additions, never. A team from the Institut de Biologie du Développement de Marseille-Luminy (CNRS/Université Aix-Marseille 2) has shattered this belief by providing proof that the exuberant helmet of Membracidae, a group of insects related to cicadas, is in fact a third pair of profoundly modified wings. . . .

How could a new pair of wings appear in Membracidae? "In insects, wing formation is normally repressed on all segments by Hox genes, except on the second and third thoracic segment," explains Gompel.
So, strange stuff. 

There are several peculiarities about these insects.  They supposedly originated 40 million years ago, but the primary thing that changed was this “helmet”?  The main thing that changed was: shape, color, and size.  The purpose seems to have remained unchanged for 40 million years.  It was probably used for camouflage.  I’m presuming without further info that different camouflage features were used for different environments, each helmet custom tailored for particular needs.  That shows surprisingly efficient adaptation.  One might even think it was designed adaptation (sarcasm).

The article implies that major additions to insect designs are rare.  Why?  It seems that the insect designs have become mostly “locked” in place and immune to evolution.  For some reason, these particular insects allowed for major changes in the helmets, but little else.  How does Darwinian evolution explain this?  I explain it by saying that macro-evolution has virtually ended, since all the new genetic information has become expressed and unused information has been mostly obliterated in genomes.

Let’s talk information and complexity for a second.  The helmets were apparently derived from the genetic information for wings, but retooled for a different purpose.  Now, wings are much more complex than these strange helmet outgrowths.  So, the helmet features are actually nothing more than a recycled wing design but turned into something with a different purpose—in this case something less impressive and less useful.  In my view, created evolution works that way: it takes existing designs (whether latent, unexpressed codes or expressed codes) and tweaks them without adding new information.

Modern adaptation consists mostly of changing body parts’ size, shape, or color.  This is precisely what happened to these helmets on these insects.  No new information came into being, but only a reuse of a body part blueprint, and size, shape, and color changes.  Keep in mind that size, shape and color changes can’t explain much of the history of evolution.  Totally new designs had to come into existence, which could not form from such simple modification of existing parts.

[Edit: Recent information has come to light that throws the whole study sited above into suspicion and shows some of the study contained incorrect information. See for more info.]

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