Outside magazine, January 1999
The Wild File
Your urgent inquiries about the world, answered
By Hampton Sides
In the Midwest, forecasters are always blaming blizzards on the "lake effect." Are they for real, or just trying to pass the buck?
— J. O'Brian, Grand Rapids, Michigan
Rest assured that lake effect is not some kind of meteorological conspiracy. It's completely legitimate; in fact, it's a global phenomenon — Russia's Lake Baikal is a notorious blizzard factory. Nowhere, however, is it stronger than in the Great Lakes region, where topographic and atmospheric conditions provide an ideal birthing ground for monster
storms. It happens like this: A stiff, cold breeze sweeps for many miles over a large body of relatively warm water (à la Lake Superior), causing cloudlets of ice crystals to evaporate like steam off the lake's surface. When the arctic winds fetch themselves to shore, these clouds — now saturated with humidity — are forced upward into
chillier realms. And because cold air holds less moisture, the bottom literally drops out, in the form of huge amounts of snow; sometimes as much as four feet can fall during a single day in narrow, localized bands. In other words, you get Buffalo and Cleveland and, yes, even Grand Rapids. But nothing compares to Marquette, Michigan, unrivaled lake-effect
capital of the world, a town situated within firing range of Lake Superior and Lake Michigan — and where the average annual snowfall is 121 inches.
How and when are organisms considered members of the same species?
— Orvin Bontrager, Aurora, Nebraska
The traditional answer is the one you learned in school: If two organisms are capable of producing fertile offspring, then they're members of the same species. Unfortunately, there are flaws to this definition, the most conspicuous of which is the fact that several species of birds and fish are known to mate successfully outside their kin. Take, for
example, mallards. "They're especially promiscuous," notes David L. Hull, an evolutionary biologist at Northwestern University. "They get a little bored with their own species," often preferring the more exotic tail feathers of, say, teal ducks. So while common sense tells us that the old concept works in most cases, Hull and his fellow "phylogenetic
systematists" have stopped using it as the crucial criterion. Instead, they've developed a complicated method of classification that focuses not on who's mating with whom, but on "evolutionary lineages" that show how and from whom organisms evolved. Identifying these minute genetic links is no small task: At this very moment, systematists are analyzing DNA
data on some two million species (living and extinct), faithfully keeping Earth's gargantuan family tree current.
I hit my funny bone frequently, so I have to ask: What is it, and where's the humor?
— Janet Garcia, Troy, New York
It's a double misnomer, actually. The "funny bone" is not a bone, and as some repeat sufferers will tell you, it's not at all funny. That hot and tingly throb you feel when you bang the inside of your elbow is the result of a direct hit to the ulnar nerve, which stretches from the shoulder to the pinkie and controls dexterity. The ulnar's claim to fame
is that it runs painfully close to the skin at the elbow. Knock it just so and you'll squash the exposed nerve against hard bone, interrupting the nervous signal and generating a kind of electric shock that shoots all the way to the fingertips — the physiological equivalent of striking a power main. Think of the funny bone as an anatomical design flaw
suffered by some of us in the upper registers of the animal kingdom (other primates such as chimpanzees and orangutans apparently experience the same problem). It's nature's way of punishing us for the hubris of sprouting arms.
|The new year begins with a bang, compliments of the full Moon on the first day of the year (one of only several such occurrences this century). On the third, Earth will reach its closest proximity to the Sun, 91 million miles distant. Good news for Mars aficionados: 1999 will be a stellar year for viewing
the red planet, as it will rise earlier and look brighter than it did in 1998; during January, Mars appears just before midnight and will be brilliant above the southern horizon in the pre-dawn twilight. Also taking center stage is the constellation Taurus, containing the cluster of stars called the Pleiades and visible overhead in the evening.
January ends as it began, with the second full Moon of the month — called the Blue Moon — on the 31st.
— Jean Quashnock
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