Curiouser and Curiouser
In his awesome
book, Labyrinths
of Reason, William Poundstone describes the generally accepted criteria
to truly “know” something:
1)
Belief: You must believe what you think you know
(e.g. “We wouldn’t say a flat-earther knows the earth is round”);
2)
Justified: There must be a valid reason why you think you know something. This is to rule out
lucky guesses;
3)
True: This feels circular, but it means that
you can’t know something unless it really is true in the first place.
Consider the topic
of antibiotics-resistant bacteria. An antibiotic resistant strain called MRSA
has been the posterchild for just that trend. It certainly feels like something
we “know”, right? Over/mis-use of antibiotics caused the bacteria to mutate and
become resistant, thereby making the antibiotic useless for further use. It
sounds right and logical.
And yet, as Ed
Yong writes,
the story of MRSA is far more complicated:
1)
The
three initial strains of MRSA were detected in patients who had never been
given the antibiotic;
2)
MRSA
appeared in India and Europe before
these countries started using the antibiotic in question!
So how could
bacteria mutate to fight an antibiotic they had never encountered?!
As researchers dug
into this cart-before-the-horse question, they sequenced the DNA of MRSA
collected between 1960 and 1989. Their stunning finding?
“By comparing these strains and
reconstructing their evolutionary history, the team calculated that they all
descended from a common ancestor that first acquired the ability to resist
methicillin in 1946 — 13 years before people
started using the drug to treat infections.”
The answer was
mind-blowing: the mecA gene that
provides immunity to the bacteria from MRSA was already out there before the antibiotic was used! But the mecA gene had its disadvantages for the
bacteria, so it didn’t spread across the bacteria population. Until, that is,
use of the antibiotic started. Because, from that point onwards, the upside of
the mecA gene outweighed its downside
for the bacteria!
The takeaway from
all this? Hsu Li Yang puts it perfectly:
“Antibiotic resistance is a web of
unintended consequences, rather than a simplistic cause-effect model that we
often find (too much) comfort in.”
The world is a
complicated web of links. With feedback loops. It is almost impossible to
“know” what impacts what else…
Interesting. This blogger seems to discuss anything under the sun - maybe far beyond the sun too, once in a while in by chance astrophysics is taken up!
ReplyDeleteOne can see the important point about "The world is a complicated web of links. With feedback loops. It is almost impossible to “know” what impacts what else…" See, even the less complicated man-made 'internet web of countless links' is mind boggling - what to speak of nature's own, which is infinite compared to human digital technology. :-0
This blog triggers another question in me. Let me introduce my point this way: Physics today has rendered the implication of Time enormously complicated. Relativity makes time a relative flow depending on the observer, in which no observer is static with respect to an absolute standard of rest. This is sufficient headache for anyone who wants to take up physics seriously! Another bewildering complication occurred in quantum physics. In the particle world, they played with an interaction with a particle which, in normal understanding, has no way of affecting another particle which has already beyond the influence of this interaction in any way. But in the weird world of quantum mechanics what happens 'now', can affect that which has already happened! This is the Hollywood-Terminator story in physics, and it is no less dramatic. The scientists actually found that future affects the past! Unbelievable but true. Introduction over - I am on to my point now.
It appears that even in biology, the future seems have a way of mingling with the past. To quote blog's lines, "...MRSA appeared in India and Europe before these countries started using the antibiotic in question! So how could bacteria mutate to fight an antibiotic they had never encountered?!" In some strange way, the bacteria seems ready right in the past to mutate in order to counter a future antibiotic. I may be putting it somewhat crudely but this could well be a valid layman doubt.
I know the scientists have their clever ways to avoid such interpretations in order to "preserve their sciences from laymen views corrupting them". Well, I look forward to the day when the biologists too admit that their own science confounds understanding and logical bounds - in the same way mathematicians and physicists had to eat their humble pies in the last century.