Editor's note: The original version of this column was published Nov. 26, 2011.
The air is cooling by at least a degree each day. The skies become impossibly blue with puffy cotton-ball clouds. The leaves are in mid-change. It's that anticipated, post-summer season again.
You also understand if you've been watching the autumn skies across Arkansas at all.
Those enormous flocks of birds heading south for the coming winter are flying in unison when suddenly their dark, pepperlike cloud makes a radical turn or dives precisely together as an airborne wave in a split second.
Not one wing nudges another as they suddenly swoop and climb and swerve this way, then that.
So how do they know? Who's in charge of this squadron, for gosh sakes?
I was pondering just such a flock above my windshield the other day. The very next day later, my daughter, Anna, called: "Dad, I have a question. How do those flocks of birds flying formations in the fall know when to turn together at the same instant?"
I had to laugh. I filed that under familial psychic connections.
Of course, being a father, I hated to confess that at this stage of life I still had not a clue. So I made something up that sounded good.
"I think there must be a leader who somehow transmits an instant message by autotomic audubon osmosis."
Hey, it sounded sorta reasonable and so authoritative, don't you think?.
Later I did confess my ignorance, which led me to do a bit of research, assuming many of you have pondered this question as well. How can we not look skyward to witness such perfect choreography without wondering what's going on?
Turns out these impossibly coordinated movements of flocks actually present one of the most intriguing questions in nature. Some who've studied the mystical question believe electromagnetic communication must be a part of it, or perhaps even the transference of a common thought between the flock.
But the phenomenon also has been called an example of "emergent behavior" among the flock itself.
"There is no leader, no overall control; instead the flock's movements are determined by the moment-by-moment decisions of individual birds, following simple rules in response to interactions with their neighbors in the flock," one explanation, posted on The Straight Dope website, reads. I had to read that passage twice and still scratched my head.
"Research by Wayne Potts, published in the journal Nature in 1984, helped explain how flock movements are initiated and coordinated," the site says. "Potts, through a frame-by-frame analysis of high-speed film of sandpiper flocks, found that any individual can initiate a flock movement, which then propagates through the flock in a wave radiating out from the initiation site.
"These 'maneuver waves' could move in any direction through the flock, including from back to front. However, the flock usually only responded to birds that banked into the flock, rather than away from it. Since birds turning away from the flock run the risk of being separated from it and getting picked off by the predator, others will not follow them. Besides its obvious benefits for individuals, this rule helps prevent indecision by the flock and permits it to respond rapidly to attack."
But there remains plenty of mystery to this question because once the wave movement begins, Potts found that it spread across the flock more rapidly than could be explained by individual birds' physical reaction times.
In the laboratory, a bird's mean startle reaction time to a light flash was measured at 38 milliseconds. Maneuver waves spread through the flock at a mean speed of fewer than 15 milliseconds. "However," reads the essay, "the first birds to respond to an initiator took 67 milliseconds to react. Potts proposed that birds farther away from the initiation site were able to see the wave approaching them, and could 'get set' to respond before it actually reached them."
Say, wait a minute. You don't suppose this phenomenon might be responsible for many of those massive bird deaths when they might mistakenly turn as a wave into catastrophic danger that wipes out the entire flock, do ya? Just thinking aloud.
And now we know that, while we humans (who usually wind up proved wrong over time in most things) might claim we understand why this phenomenon occurs, there's still much to it about which we share zero authentic understanding.
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Mike Masterson's column appears regularly in the Arkansas Democrat-Gazette. Email him at mmasterson@arkansasonline.com.
Editorial on 10/23/2016