The Redundancy in Genes (and Musician’s Brains)


Redundant networks

The latest issue of my favorite magazine, Nautilus, has an interesting article by Philip Ball entitled “The Strange Inevitability of Evolution,” in which the author explores the “creative” mechanisms that enable evolution to occur.

Pivotal to genetic innovation, it turns out, may be structures of redundancy, which we’ve explored here before as a critical aspect of resilient ecosystems.

The structure of redundancy can be viewed in the “RNA sequence space”:

First, there are many, many possible sequences that will all serve the same function. If evolution is “searching” for that function by natural selection, it has an awful lot of viable solutions to choose from. Second, the space, while unthinkably vast and multi-dimensional, is navigable: You can change the genotype neutrally, without losing the all-important phenotype. So this is why the RNAs are evolvable at all: not because evolution has the time to sift through the impossibly large number of variations to find the ones that work, but because there are so many that do work, and they’re connected to one another.

This redundant structure can also be viewed, according to the article, in proteins and gene circuits. In fact, evolutionary biologist Andreas Wagner of the University of Zurich and “his coworkers have discovered that this “evolvable” (they call it a robust) structure is a common feature of biological complexity.”

This helps to explain a puzzling aspect of gene circuits: their robustness. . . . You can obliterate many of their individual genes to no obvious effect. But this is no surprise if there are plenty of similar gene circuits that do much the same job as the original one. Looked at this way, robustness is complementary to innovation: Any network that can evolve new features and forms among a vast array of alternatives must necessarily be robust against small changes, because it almost certainly has an alternative on hand that performs equally well. This realization offers an antidote to an excessively deterministic view of genes: Exactly which genes you have may not matter so much (within reason), because the job they do is more a property of the network in which they are embedded.

Again, this feature of “robustness” is another aspect we’ve explored as a facet of resilient systems facing complexity.

As the article notes, this is not solely a feature of biological systems:

Karthik Raman, a former postdoc in Wagner’s lab, now at the Indian Institute of Technology Madras, has studied much the same issues of functional equivalence of different circuits not for genes but for electronic components that carry out binary logic functions. By randomly rewiring circuits of 16 components and figuring out which of them will perform particular logic operations, Raman found that they too have this evolvable topology.8 But crucially, this property appeared only if the circuits were complex enough—if they had too few components, small changes destroyed their function. “The more complex they are, the more rewiring they tolerate,” says Wagner. Not only does this open up possibilities for electronic circuit design using Darwinian principles, but it suggests that evolvability, and the corollary of creativity or innovability, is a fundamental feature of complex networks like those found in biology. [bold added]

This is an interesting point. If a system is not deeply interconnected, then it is more fragile and susceptible to change. This is a feature, it turns out, of our brains.

Learning—and Playing Music—Makes Our Brains More Resilient

This reminds me of a study that I posted about back in 2012, in which we learned that workers with more education proved more resilient when faced with exposure to toxic chemicals.

Interestingly enough, in the same issue of Nautilus as the one explored above, there’s an article by Brian Gallagher entitled “Brain Damage Saved His Music,” which also extends this idea. The article refers to jazz guitarist Pat Martino, who had a large chunk of his left temporal lobe removed. To the surprise of neuroscientists and physicians, Pat demonstrated a remarkable recovery when he picked up his guitar again—which somehow restored some of his memory, as well as his gift for virtuoso jazz guitar playing.

Diana Omigie, lead author of the study, and a research fellow at the Max Planck Institute, explained that larger gray matter volumes in motor and auditory regions in musicians than in non-musicians would create a brain reserve,” which “in turn might be enough to fuel relearning or recovery of a musical function.” . . . 

Omigie echoes the point that Martino’s brain, long before it hemorrhaged or Martino even knew about his tangled veins, reorganized itself in a way that might shield it from damage. “In our review,” Omigie said, “we observed that musicians who underwent surgery for early lesion, cerebral malformations, or slow growing tumors, showed a larger likelihood of recovering cognitive function than those who, for instance, had a stroke and therefore suddenly lost a large amount of healthy normally functioning tissue. The reason is that in the case of slow-forming lesions, some reorganization might have occurred such that over time, the musical function was able to transfer to other parts of the brain and leave the damaged portions less necessary.” [bold added]

We can see here the ecological principles of interconnectedness and redundancy.

Learning, especially the sort of learning that occurs when pushing the boundaries of improvisation and creativity such when playing jazz music, builds redundant connections in the brain that creates resiliency and robustness when faced with volatility.

Back to Public Education

So what might be some possible lessons for schools and school systems?

  • Build and reinforce connections within schools
    • Interdisciplinary connections between content areas
    • Physical connections between classes and common areas
    • Consistent and regular meetings of both grade-level and departmental teams (professional learning communities, what-have-you)
    • Many different extracurricular opportunities (arts, music, robotics, dance, etc) for students
    • Invest in staff members who perform “auxiliary” functions that may seem “redundant,” such as literacy specialists, librarians, data specialists, lunch aides, and so on
  • Build and maintain connections between schools
    • Cross and inter- district collaboration
    • Engagement with online learning communities and content for cross state and national alignment
  • Build meaningful bridges with scholars, researchers, and policymakers
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