From: Jeff Davis (jrd1415@yahoo.com)
Date: Fri Jul 11 2003 - 03:36:22 MDT
--- Spike <spike66@comcast.net> wrote:
> From: Damien Broderick ...irrascible immunologist,
> Malcolm Simons, now
> dying of cancer who decided years ago that `junk
> DNA' (introns) couldn't
> possibly be junk, because it'd have been darwinnowed
> out...Damien
> Broderick
>
>
> This irrascible immunologist clearly was
> never a programmer. Had he been a software
> developer, it would be clear to him how it
> happens that pieces of dead code can remain
> in the final product, even after many versions
> of the software. There would need to be some
> evolutionary pressure to reduce or darwinnow
> the dead code, which there evidently isn't.
>
> But how does one achieve the title irrascible?
> Must one have a rascer or rascist attempt to
> rasc one and find it difficult or impossible?
I'm with Simons on this one. Ever since the term
"junk dna" gained currency, I've wondered why someone
hasn't challenged the notion. Breathtakingly arrogant
if you ask me. Just because someone came up with the
idea and coined the phrase, hardly makes it true. Can
it really be said--having barely embarked on the
journey of discovery-- that we know enough about the
function of dna to declare the apparent 'excess' to be
junk. This is way way over the top presumptuous.
Nature 'believes' in efficiency. Fitness and
efficiency go hand in hand. It took an awful lot of
energy to make all that 'junk'. Another organism
looking to compete for a given niche would have a
serious advantage when not burdened by the need to
synthesize and carry around all that 'junk'. I'm not
buyin' it.
My money's on Occam's razor. The simplest--and
glaring-- explanation by far is human ignorance and
overreaching. The utility of the 'extra' dna awaits
the gradual elaboration of the grand scheme.
I've heard tell that for birds, evolution winnowed the
cargo of dna, the better for the birdies to get and
stay airborne. Or so the theory goes. If indeed
evolution trimmed their dna, then we have a proof of
principle re dna trimming for fitness purposes. The
profligate and wasteful production of 'junk' dna
similarly seems an idea too heavily freighted to get
off the ground.
I don't have much in the way of fact here, to back up
my objection, so shoot me down if you will.
Some time ago, when I first got annoyed at the seeming
presumptuousness of the 'junk' dna concept, I wondered
if perhaps the 'junk' might be preferentially
distributed in the outer layers of the nuclear
package, providing a 'shield' for the really vital
'inner' bits. You know. Whatever nasty dna-degrading
agencies--free radicals, mutagenic compounds, ionizing
radiation--runnin' around loose in the cytosol, would
have to get past the protective/sacrificial outer
layers before thay could do any 'real' damage. Just
an idea.
Best, Jeff Davis
"When I am working on a problem I never think about
beauty. I only think about how to solve the problem.
But when I have finished, if the solution is not
beautiful, I know it is wrong."
- Buckminster Fuller
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