Adaptive plasticity, or why I can't find anyone.

Phenotypic plasticity is a common occurrence in biological systems, and can be defined as a single genetic "type" (population, species) exhibiting an array of phenotypes (physical forms), often in response to their environment.  Examples abound - grow Daphnia (water flea) in the presence of predators, and they develop a pronounced head spike.  Maples turn color in the fall as the colder temperatures trigger them to break down their chlorophyll, leaving other pigments to become visible.  And so on.

I have an interest in phenotypic plasticity, using snails as my model system.  One question that remains unanswered in snails and other mollusks is "why do shells have colors and patterns?"  There are two easily understood explanations.  One is camouflage; the color pattern allows the shell to blend into its environment, thus protecting it from attack or predation.  The other is the breaking of a search pattern.  Predators learn what prey/food looks and acts like.  So, if every individual prey item looks different, the predator can't key in on what is edible and moves on.  Sort of anti-camouflage.

I bring this up because I recently went to the casino in Milwaukee with my parents.  We had been there a few hours, and I went looking for them because I was ready to go and needed to see what they were up to.   My dad wears clothes that accentuate his Japanese eggplant shape, my mom loves her pull-on knits; both of them wobble when they walk after the accident.  I mention this not to criticize my parents, but to point out that they have an obvious phenotype.  When we are walking around the casinos in Vicksburg and Shreveport, they are easy to spot.  However, on their home turf, they blended right in.

 Another form of plasticity is mimicry, where one organism models their appearance after another.  This is meant to confuse predators by tricking them into thinking a harmless individual is actually very dangerous.  As I wandered around the casino, I fell for no fewer than 10 "parent mimics" - similar clothes, similar gaits, etc.  Luckily I didn't actually interact with any of them, but it was a little more than frustrating to wade through a sea of elderly smoking women precariously hooked to oxygen tanks just to find that the person you thought was your mom is actually someone else's mom who looks scornfully at you for potentially breaking their mojo on a slot machine.

This continued for over an hour; at least I got some exercise that day.  Just as I rounded a corner for the last time, I heard my name being paged.  I met my parents at the valet area.  Supposedly they had been sitting in spot X for most of the afternoon, and I of course just walked by them 4 bazillion times.  Adaptation at it's finest - we will only be found when we want to be.  And all other times, we will fade into our surroundings like so many peppered moths.

Next time I will plan ahead, ether by attaching a bell to their waists, or by implanting small GPS antennas in their shoes or something.  I will not again be foiled by two sixty-year old adults confusing me like a robin is fooled by the lovely viceroy.  Well, at least I hope my parents don't want me to think they are trying to poison me.