Field Report to the Academy of Natural History on Evolutionary Behaviour
of Sciurus carolinensis
the squirrel crossed the road.
We are in
the middle of the peak months for squirrel road fatalities again. The
body count is high. Small carcasses dot the asphalt. Ravens use these
little grey road bumps much like social clubs, catching up on avian gossip
and exchanging jokes while snacking on crêpe d asphalte. Hey,
know why the chicken crossed the road?
.to show the squirrel it could
actually be done!
A wet summer
here in the east has caused the trees to convert most of their sun-produced
sugars into growth as opposed to a hefty crop of nuts and berries.
This dictates that the common gray squirrel, Sciurus carolinensis, must
travel further distances to gather acorns for the upcoming winter. There
are those squirrels lucky enough to live in a territory uncrossed by pavement.
Their evolution is left unchecked by human interference. Others are confined
to territories where squirrel-v-tread tragedies are played out on an hourly
basis. Their evolution is an ongoing process dictated by speed signs,
tire width, number of axles and their own reaction times.
I have documentation
that proves squirrels living in high traffic areas can be classified into
Crossers - Those who run across the road, totally indifferent
to any threat.
No-Crossers - Those who, prior to setting foot on the asphalt,
change their minds in the face of an oncoming automotive threat and flee
in a direction away from the road. They are on the opposite end of the
spectrum from the Bold Crossers.
Mid-Roaders - Those who change their minds while on any
part of the street and reverse their direction (this group also includes
those squirrels who zig-zag across lanes or run parallel with traffic
while the decision-making part of their little brain randomly fires left-right,
stop-go signals to their little legs).
our understanding, I began to tally these three groups to see if an underlying
commonality could be deduced. For a period of roughly two weeks I classified
187 squirrel encounters as I made routine trips through town:
1 - 129 squirrels or 68.9% of the sampleThe
No Crossers/Group 2 - 49 squirrels or 26.2% of the sampleThe
Mid-Roaders/Group 3 - 9 squirrels or 4.8% of the sample. **
** I personally
ran over two of these. The first was a halfback (got halfway across and
decided to go back) the other was a zig-zagger (far less common).
If you are
a statistician or are familiar with standard deviations the percentages
should be very familiar.
The population of Group 1 closely corresponds in number to the One-Sigma
standard deviation grouping of 68.6% of a total population of 100%. Group
2 corresponds likewise with the Two-Sigma grouping of 26.8% and Group
3 corresponds with the Three-Sigma grouping of 4.6%.
From these numbers and my own personal observation it can be surmised
that the Three-Sigma group is slowly and un-naturally being eliminated
from the population.
In addition, the One-Sigma group is suffering a higher attrition rate
than the Two-Sigma as the Two-Sigs, being asphalt shy, will not be found
in any road fatality group (off-road fatalities are beyond the scope of
this report). I would venture to guess that the vast number of squirrel
fatalities were from the Three-Sigma group with a few from the One-Sigma
Trapping, tagging and observation is required to verify this hypothesis.
I presently have a number of research grant applications submitted.
fatalities are inducing genetic drift in the general squirrel population
that counters 100 million years of natural selection based. Is not the
unpredictability of a squirrels retreat its sole defense against
predators? Is not the inability of a squirrel to decide which way to flee
the single characteristic that saves it from death by jaws or talons?
It seems that the evolutionary roadmap is being redrawn to eliminate that
group of individuals from which ancient squirrels obtained their best
This has artificially induced an instance of Punctuated Equilibrium- that
evolution occurs in huge and sudden jumps.
generations, being a Three-Sig squirrel placed you in the top echelons
of the breeding population. You were a stud. You were a playa
in the squirrel hood. I can only guess how the Three-Sig label might translate
to social interaction of squirrels in this generation.
Would it be a badge of honor or of disrepute? The Three-Sigma grouping
of any population includes actually two groups: those on the very upper
end of the bell curve AND those on the very lower end.
The fastest and the slowest, the heaviest and the lightest, the happiest
and the saddest.
Putting it in terms of I.Q., the Three-Sigma sample of a population includes
the 2.4% of the population that is in the genius range on the high end
of the bell curve and also the 2.4% of the population that is in the comatose/brain-dead
range on the low end.
This leads to an observation that directly applies to most any animal
Whether you are a genius squirrel or a squirrel who does not know which
end of the nut to crack first, your average life expectancy will be the
same bleakly low number.
Brains dont count diddly.
Your longevity is inversely proportional to the distance your behavior
lands you from the statistical mean.
In present times, inability to make a decision will increase the likelihood
of getting flattened, of going from vertebrate to invertebrate in the
squeal of a tire.
In the midst of traffic the genius squirrel in the Three-Sigma group -
the Mr. Spock of the squirrel world - is logically deducing the safest
course of action, all variables considered in the calculation, the instant
it is run over. The stupid one, the Dumb and the Dumber, is just screaming
Yet, they both run identical patterns directly to their little chalk outlines
on the pavement.
age group must be a determining variable of social labeling. In all populations
the youngsters equate danger with a positive labeling while the adults
equate it with negative. I can imagine the juveniles hanging out on the
power line one day.
One juvenile points to his erratic uncle on the pavement below and proudly
proclaims: MY Uncle Chip is a THREE-SIGMA. All the other juvies
go Oooooooo as Chip disappears under a car.
Or, when saying their prayers at night: Bless Barky, bless Wire
Runner, bless Grey Jumper
.and please let me grow up to be a Three-Siggie
so Ill be cool and everyone will like me.
the parents are saying in their nightly prayers:
over Little Grey Paws.
Make him a Two-Sigma.
Dont kill him in some senseless nut-gathering accident. I
strongly suspect that there is remedial schooling for young squirrels
identified through testing as being outside the Two-Sigma grouping.
Squirrel parents send their One and Three Siggies off to military convents
If the training is not successful, are the Three-Sigmas stigmatized as
not the kind of material suitable for raising pups?
Are they pushed into lower social classes? I have observed and documented
groups of squirrels spending their days eating fermented acorns and playing
Black Wire Roulette at the local transformer.
Come on Scruffer
one more nibble on the black wire
us all you can do it
Bite! Bite! Bite! Bite! Bite!
bookies handicap bets on street crossing based on a Sigma Rating of the
Do the Three-Siggies earn higher odds? Can a shy Two-Sigma squirrel be
intimidated into throwing a bet? Gee
didnt make it across.
The racing sheet says he was a Two-Sig non-crosser but you know these
numbers can be wrong sometimes.
Is there a wall of honor in some hollowed-out tree in some ancient forest
where the engraved names of all past Three-Siggies hang on little wooden
The St. Andrews of tree dwellers?
I came across
an anomalous squirrel the other day that defied any label I was familiar
The I-240 Loop around town is one of those brainchild highway projects
that is the product of an over-funded State Transportation Department.
An eight-lane highway befitting Los Angeles complete with a wide landscaped
median that skirts a town of only 70,000. A line item in a bloated budget
of years past.
Since the drive time across town is roughly 13 minutes any way you go,
building 240 was equivalent to putting tits on a Winnebago.
I was driving down I-240 and about 20 car lengths ahead I spot a squirrel
sitting directly atop the white-striped line in the middle of the four
As I bore down on it at 70-miles per hour, I could see that it was standing
on its haunches staring directly into oncoming traffic. Its tail
was whipping back and forth with every passing car, but It was not moving
a term used by those who pursue dangerous past-times for the sake of self-gratification.
This term applies when one achieves a milestone of bravery or endurance
in an anonymous manner.
The term is Silent Glory.
Prior to Sir Edmund Hillary and George Mallory, there was George Ingle
Finch. He took to the top of Everest just to
have a good walk
keeps me out of the bars and the Missus happy and made it to 27,000
feet (1,128 feet short of the top). He wasnt into the climb for
the fame and fortune but for the personal goal and didnt care if
anyone knew about it. After Finch was Edward Norton and Theodore Somervell,
two Englishmen who repeated the feat but without supplemental oxygen.
Oxee-gen? Whas thot??? They were purists.
Perhaps this squirrel standing in the middle of four lanes of oncoming
interstate traffic was the George Ingle Finch of squirreldom. The one
squirrel out of the entire worldwide population who stares down four lanes
of oncoming traffic FOR THE SHEAR JOY OF DOING IT. Unannounced personal
gratification. He keeps the accomplishment to himself.
Forever un-rewarded by his fellow squirrels. Basking in solitude in the
warm glow of Silent Glory atop his own personal Everest.
I tipped my hat as I sped by this little warrior.
Sir, I will
keep your secret.
apply a Four-Sigma label to a squirrel like this because Four-Sigma
does not exist.
Its like saying One-hundred thirty-two and a half percent.
I can only suggest that this squirrel was a penultimate example of Punctuated
Equilibrium- an evolutionary discontinuity.
A genetic anomaly where a road crossing decision matrix was not included
in its genetic soup.
It represents the beginning of a branch in the evolutionary tree where
ones remaining on the painted centerline is based solely on hedonistic
gratification. As his genes spread through the general population, shall
we be seeing his offspring duplicating this feat? Will there be little
grey ones sanding casually in formation to face the morning rush hour?
Will they be mowed down like dominoes, only to be replaced by their fearless
It is entirely possible.
Genetic anomalies of no consequence or sensibility have become common
in some isolated populations of Sciurus carolinensis. Case in point:
County in Western North Carolina (yeah, it is actually called Transylvania
just like the Dracula movies), there exists a small population of squirrels
isolated by mountains on all sides that have defied laws of natural selection.
Their genetic mutation makes the fur of these squirrels white (Dont
believe me? Do the web search). They are not albino squirrels, but common
gray squirrels that grow white fur.
Now explain to me how this white fur provides an advantage in predator
avoidance or reproduction, the two primary determinants of an evolutionary
step. Evidently, human success at destroying birds of prey that would
use this defect to their advantage has played a major part.
A white squirrel wandering across a front yard on a summers day
might as well have a Very Tasty and Slow sign taped to its
back for all hawks and owls to see. White fir is definitely classified
as a three-sigma event. It is off to one side of the bell curve as much
as pink fir with orange polka dots would be.
I hiked around Transylvania County for a few years trying to find one
of these illusive white squirrels, but to no avail. I heard about them
from friends while sipping scotch at cocktail parties and read newspaper
articles describing huge populations flourishing in the hollows and ravines
of the mountains. Trees turned white with the critters, branches bending
under the weight.
I never saw one in the flesh.
day I was lucky enough to spot one after picking my child up from a friends
This white squirrel ran unfazed across all five lanes of a state highway.
One-Sigma (behavior) Three-Sigma (coloring).
Think about it for a second.
What is the statistical probability of seeing a One-Sigma WHITE squirrel
on a road in action after not having spotted ANY white squirrels while
hiking their territory for the previous 5 years?
The odds have got to be about zero in minus two. Yet, there it was for
a few fleeting moments. It took a few seconds for me to realize I had
actually seen a squirrel because my first impression was that I had seen
a very fast ferret.
It was highly unusual, but I have to point out that there is one occurrence
that is statistically less probable
.observing a THREE-SIG THREE-SIG
(Three-Sig squared???) run a five-lane gauntlet AND LIVE. This could quite
possibly be The Holy Grail of amateur zoology for those of us who are
keen observers of squirrel behavior. A Three-Sig Three-Sig is an event
I may not observe in my lifetime, but I do keep up hope in the possibility
that fate will fall in my favor.
continue to make accurate scientific observations related to the genetics
and behaviour of Sciurus carolinensis and submit regular field reports
to the Board of The Academy for publication and open debate.
© 2002 SLM. All rights reserved.