Wednesday, September 4, 2013

Vertical vs horizontal resistance. Co-evolution

Picture from here

The rabbits get faster and the fox gets faster.

This guy "gets" it.  He is writing about securing your garage but his methods and perspective can apply to many venues.
"None of these things are absolute defenses, but each one involves a layer of time and hassle – for the thief. The greater the time/hassle factor involved, the less appealing your stuff is to thieves."


Imagine a plant (the rabbit) that develops a mutation that causes the leaf to repel water, thus making it difficult for a disease organism (the fox) to gain entry.
Droplets with silvery under-sheen are perched on tiny hairs.  Darker green where no water is beaded up is where droplets finally overcame hairs.  Dwarf Siberian Kale leaf, picture taken September 16, 2013 about 14 hours after rain fall.

The plant now possesses a huge competitive advantage relative to its neighbors and soon dominates the scene.  Given enough time, a disease organism will develop a mutation that impairs its waste product elimination such that it produces soapy wastes.  This "defect" allows the disease organism to overcome the plant's defenses.

The plant went from a single defense that conferred absolute immunity to a defense that may have slowed down the disease organism but no longer stops it.  The plant exhibited "vertical resistance" when the single defense was 100% effective.  The defense still offers partial protection so it is likely to manifest in the majority of the population...but it is no longer a slam-dunk defense.

In time, an individual plant may develop a mutation where it has "dirty" metabolic processes or inefficient waste elimination.  That will allow a build up of phenolic compounds called tannins.  Those tannins will stymie the disease until it evolves a counter-measure.

The plant and the disease co-evolve.  The rabbits get faster and the fox gets faster.  The plants, as a population, develop a portfolio of defense strategies.  The accumulation of partially effective, overlapping defenses are called "horizontal resistance" and are much more difficult to defeat, in total, than vertical resistance.

Much of the science of modern crop breeding involves identifying ancillary defenses to bolster well documented "vertical" resistance.  Because when "vertical" resistance collapses the result can be a spectacular failure.

The concept of vertical vs horizontal resistance is a theme I intend to revisit on a regular basis.

In human affairs:

It is likely that villages always had a ghetto that housed human "waste".  That is where the damaged people went.  The embarrassments.  The products of rape by invaders, the mentally ill, the people born with birth defects, the "monsters", albinos and other mutations.

The ghettos supplied the people to perform unclean jobs...the untouchables.  They likely housed the brothels and were a place that criminals could hide.  For the Biblically literate, it is possible that the Samaritan woman in John 4 lived in such a ghetto...she was a despised minority who killed off her husbands faster than Typhoid Mary.

These ghettos provided a place where inbreeding could become quite intense.   They were a place where rare, recessive genes could find each other and reinforce each other.  Those ghettos were places where the evolutionary stepping stones for proto-porcupines could survive long enough create true porcupines.

Those albinos provided the break-through that allowed humans to wear heavy clothing, live in dark dwellings in Northern regions much deficient in light....and still synthesize enough Vitamin D to thrive.  The ghetto was the salvation.

Referring back to our plant example;  there may have been a smoldering population of the plant with the defective metabolic process and waste elimination process all along.  Those plants would be crippled by the toxic effects of the tannin and would struggle to compete head-to-head with the taller plants that did not have the burden of the toxins.  They would struggle until the challenge from the disease flipped the selection process on its head.  After that, the high tannin plants would have a huge reproductive advantage over the yummy plants with the "pure" processes.


One of the elegant features of the Internet is that many small communities can share ideas, can hone and refine concepts.  The whack-job with the tinfoil hat may start the ball rolling.  Recursion and "playing with" by good minds test everything and keep what is good.

The universe is a chaotic and messy place.  It is not well behaved.

Many can end up standing atop "the highest mountain" and have it all to themselves.  It simple depends on where they started.  The bottom of the Pacific Ocean, Asia, Alaska, Chile, or the Martian plains of Tharsis.

Picture from here.

One's starting point matters hugely.

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