Friday, January 30, 2009

Rumbling on Redoubt

Towering above Cook Inlet, Mt. Redoubt, at 10,200 feet, is one of the largest volcanoes in Alaska and one of four that pose a threat to Anchorage, the State's largest city. Over the past few weeks, geologists have detected the telltale signs of an imminent eruption which, in this mountain's case, last occurred in 1989-90; on that occasion, the volcano sent rivers of caustic mud into nearby streams and spewed abrasive ash 40,000 feet into the atmosphere. The latter almost brought down one passenger jet and disrupted air travel across much of western North America.

According to the Alaska Volcano Observatory, the State has over 130 volcanoes and volcanic fields, of which more than 50 have been active in the past 250 years; over the past forty years, Alaska has averaged 2 eruptions per year. The great majority of these active volcanoes are in the Aleutian Chain which formed (and continues to form) as a volcanic island arc, just north of the Aleutian Trench; within the latter, the Pacific Plate subducts beneath the North American Plate and its melting (as it nears the mantle) feeds the volcanic activity. Mt. Cleveland, in the central Aleutians, has erupted at least 11 times in the past 25 years.

Earthquakes and volcanism are the most potent reminders that our planet's evolution, which began 4.6 billion years ago, continues today. We are not the culmination of natural history; rather, we are part of it.

Wednesday, January 28, 2009

A Swath of Ice

This week's winter storm has produced a swath of ice from Oklahoma to the Mid-Atlantic region; western Kentucky appears to be ground zero. Since ice accumulation brings down tree limbs and power lines, ice storms, often occurring over broad regions, are among the most destructive weather events on our Continent.

The development of an ice storm requires three ingredients: cold air at the surface, overriding warm, moist air and a system that is moving fast enough to keep that contrast in place. The cold surface air keeps the temperature of roads, buildings, trees and power lines below the freezing point while the storm's circulation sweeps warm, moist air up from the south, lifting it above the cold layer. This lifting generates precipitation in the upper atmosphere; if the cold, surface layer is thick, the precipitation will reach the ground as sleet or snow but, if the cold layer is thin, it will arrive as rain, freezing as it strikes the ground structures. Building up over time, the heavy ice brings down limbs and power lines.

If the storm is moving slowly, the southerly flow may warm the surface above freezing before the lift and precipitation occur. In this case, a mix of sleet and rain generally develops along the cold front, with snow to the north and rain to the south. Predicting an ice storm is thus difficult, since its extent (west to east) and width (north to south) will be determined by multiple factors, all of which remain in flux.

Tuesday, January 27, 2009

Winter Kill

Despite its stark beauty, winter is the season of death. Exhausted by the autumn rut, many aging bulls, stags and bucks will succumb to the cold and snow. Yearlings, too small to navigate the deep snows, are a favorite target of predators and even healthy adults, naturally equipped for northern latitudes, may not survive blizzards or prolonged, severe cold.

Of course, nature's economy assures that this carnage will not be wasted. Wolves, coyotes, fox, eagles, magpies, ravens and a variety of small carnivores feast on the carrion, assuring their own survival through the lean, winter months. And when the thaw finally arrives, the remnants will be recycled by mice, shrews, insects, worms, fungi and bacteria.

While survival is the focus of most winter wildlife, some have other plans. Great horned owls, tree squirrels and cottontails begin their breeding cycle during the latter half of winter and will soon have young in the nest. Like all seasons, winter is a balance of natural forces and, while death may have the upper hand, life endures.

Monday, January 26, 2009

A Promise of Snow

While it's been an especially cold winter, we've had very little snow in central Missouri. But, according to the weather gurus, that is about to change.

A new winter storm, gathering strength in the Southwest, is about to move eastward, pulling Gulf moisture up and over the entrenched cold air (currently 13 F in Columbia). We are expected to receive at least 6 inches of snow over the next two days while areas to our south are bracing for an ice storm. Compared to the ice, our snow will be a mild inconvenience and, for many of us, a welcome development.

Though it can be a nightmare for travelers, there's nothing like a good snowstorm to certify the winter season. And there is no better way to beautify the urban landscape, especially when followed by brilliant sunshine or a full moon. If it makes us slow down for a few days, all the better!

Sunday, January 25, 2009

Unexpected Sightings

Though I have been a birder for thirty years and a nature buff since childhood, I witnessed two natural spectacles yesterday that I had never seen before. On my drive back from Colorado, a flock of 200 or more meadowlarks crossed the highway west of Salina and, in bottomlands near Topeka, I saw a flock of at least 60 wild turkeys.

Neither would likely be classified as rare or unusual events; there was no need to contact the Kansas birding clubs to report either sighting. But while many birds, including these two species, gather in sizable flocks during the colder months, I had never seen such large congregations of either species over the years. And for someone who has spent a large amount of time tramping around nature preserves and open space, that's saying something.

Such is the motivation and inspiration for nature study. One never knows what to expect, even on a bleak, cold day in Kansas.

Saturday, January 24, 2009

Ribbons of Death

Those who drive America's Interstates know that any wild mammal that they see along the highway is far more likely to be dead than alive. The most common victims are deer, raccoons, opossums and a host of small mammals; however, on my trip to Colorado this week, I saw at least six coyotes among the roadkill. And just yesterday morning, a trucker plowed into a herd of elk in the Front Range foothills, killing sixteen of those magnificent animals; fortunately, early reports indicate that the driver was not seriously injured.

Almost all of these mammal-vehicle collisions occur at night, when the animals are most active and when visibility is limited. Many, if not most, Americans may be unmoved by these events, pointing out that these common creatures would otherwise be contributing to the destruction of residential or agricultural plants. Then again, the wild mammal is not always the only victim of these collisions, especially when deer, elk, moose or other large species are involved. It seems to me that efforts to reduce these unfortunate events are warranted; a lower night speed limit in high risk areas would be a start.

Many Americans would probably label this piece as foolhardy ecodribble from an over zealous conservationist; I plead guilty! But roadkill is just one more way in which humans have a negative impact on natural ecosystems. Besides, we are all hurtling toward death and there's no reason to shorten the process.

Friday, January 23, 2009

The La Sals

Long enamored with mountains, I am especially inspired by lone peaks or mountain clusters that tower above the surrounding desert, grassland or forest. Most of these isolated highlands, not part of an extensive range, are volcanic, laccolithic or fault block in origin. There are many such mountains in the U.S., including some of the major Cascade volcanoes, the San Francisco Mountains of northern Arizona, the Tetons of Wyoming, the Black Hills of South Dakota and Mt. Katahdin, in Maine; the greatest concentration of these isolated peaks and small ranges are across the Great Basin, where the crust is being pulled apart and numerous fault blocks have developed.

Among these isolated peaks, my personal favorites are the La Sal Mountains of eastern Utah. Thanks to the writings of Edward Abbey (most notably, Desert Solitaire), I imagined this mountain cluster long before I saw them. Since that time, I have camped and hiked among these peaks, observed them on numerous road trips and spotted them from the air; they never fail to stir my soul. With multiple summits above 12,500 feet, the La Sals are the most concentrated collection of high peaks in the State, though higher summits can be found in the High Uintas. The La Sals have been carved from a massive laccolith, which rose during the Miocene-Pliocene Uplift; now towering between the Colorado River, to the west, and the Dolores River Canyon, to the east, these lofty mountains send numerous tributaries into those larger streams.

Rising to the east and southeast of the Canyonlands and Arches National Parks, the La Sals are a popular background for postcard photos and are surely in the personal photo collection of anyone who has visited these scenic parklands. For those of us who have these rugged peaks in our souls, photos are enjoyed but unnecessary.

Thursday, January 22, 2009

An Omen to the West

After almost a week of summer-like days in Metro Denver, a change looms to the west. Pacific moisture is streaming into the State and a cold front is dropping from Canada; this combination will soon produce upslope snow west of the Divide, as evidenced by cloud formations above the Front Range.

A band of dark clouds had formed behind the snow-capped peaks this morning and, by this afternoon, most of these high summits were enveloped in "spill over" moisture. Meanwhile, on the Piedmont, downsloping winds persisted, bringing us partly cloudy skies and high temperatures near 70F. But by tomorrow, as the front sweeps to the southeast, we will be on its chilly side, with seasonable temperatures and intermittent showers (rain or snow).

Though the mountains have received significant snow this season, the East Slope is well below average. Then again, our heaviest snows fall in March and April, when Gulf moisture invades the Plains and the jet stream directs storms across southern Colorado. That is our upslope season!

Wednesday, January 21, 2009

The Castle Rock Mesas

Those who travel between Denver and Colorado Springs are familiar with the scenic, mesa and valley terrain, north of the Palmer Divide. Contrasting with the stark wall of the Front Range foothills, this territory looks like it belongs in Western Colorado, where the rim of the Colorado Plateau curves through the State.

The geologic history of this topography dates back to the Oligocene, about 34 million years ago, when the ancestral South Platte, then a massive, braided river, flowed eastward out of the young Rocky Mountains. At that time, the mountains were nearly buried in their own erosional debris and recent volcanism (near present-day Salida) had spread an apron of ash across much of the region. The ancestral river, carrying rocks, pebbles and sand from the mountains, mixed and welded these fragments into a hard, conglomerate rock, the matrix of which contains the volcanic ash.

Further mountain uplift during the Miocene-Pliocene, combined with increased precipitation during the Pleistocene, altered the course of the South Platte River and augmented the erosive force of its tributaries; the latter include Plum Creek and Cherry Creek, which rise along the Palmer Divide and flow northward to join the South Platte. These two streams and their tributaries have eroded the mesas (protected by hard caps of Castle Rock conglomerate) from the surrounding plains, leaving the scenic landscape that we find today.

Avian Rush Hour

During the colder months, having completed their parental duties, many birds roost in large flocks. Come morning, they scatter across the countryside, usually feeding in small groups, and then return to the roost during the last hours of daylight. This behavior likely evolved as a means of protection; numerous eyes and ears offer better detection of predators and the hunter may be overwhelmed by the huge number of potential targets. Furthermore, such roosts are often established on naturally protected sites such as islands, isolated groves, remote beaches or, in the case of waterfowl, out in the middle of a lake; such locations make it difficult for a predator to attack without early detection.

Though we may not know where the roosts are, we certainly can observe the traffic as birds head toward these sites late in the day. In Missouri, as is typical throughout the eastern U.S., these gathering flocks are usually composed of blackbirds (starlings, grackles, crows, redwings) or robins; at times, a river of birds may stretch across the evening sky as they make their way to the nightly roost. Along southern coasts, this daily rush hour is composed of various waders (herons, egrets, ibis), gulls, terns, cormorants, pelicans and shorebirds, making their way to secluded beaches or mangrove islands.

Here along the Front Range, Canada geese and ring-billed gulls are the primary winter commuters, heading back to favored lakes and reservoirs throughout the area. By spending the night on the open water, or in the middle of a frozen lake, they are well protected from the coyotes and fox that hunt the darkness. When the sun returns, they will head out to feed on grasslands, along the South Platte or, for many of the gulls, at landfills and parking lots.

Tuesday, January 20, 2009

A Time for Hope

Man has always been a tribal and territorial creature, as evidenced by our long history of allegiance to clans, empires, religious sects, countries, cultures, political parties and sports teams. Unfortunately, this trait has ignited war, famine, discrimination, revolution and intolerance throughout the years.

Today, with the inauguration of Barack Obama, the first minority President of the U.S. and a man who seems committed to communication rather than confrontation, there is reason to hope that humans may begin to choose a different course. Having just survived eight years of ignorance, militarism and cowboy diplomacy, we have elected someone who, hopefully, will allow America to lead by example, not by intervention.

Whether Obama's leadership will be enough to overcome the self-righteous zealotry of many religious, political and nationalist groups remains uncertain. But, as they say, it's darkest just before the dawn.... and it can't get much darker.

Monday, January 19, 2009

West with the Moon

Leaving Salina in the early morning darkness, I headed west on I-70, bound for our farm in Littleton, Colorado. A waning moon, high in the southern sky, lit my path for the initial stretch, giving the wind turbines near Ellsworth a ghostly appearance.

Dawn broke as I neared Russell and the sun rose in my rear view mirror just east of WaKeeney. As the sky brightened, the moon lost its brilliance but remained ever present as I crossed the High Plains, where cattle grazed the stubble, harriers patrolled the fields and tumbleweeds(Russian thistle), caught in a strong north wind, strafed the highway like alien swarms.

Gradually moving ahead of my pace, the moon "approached" Pike's Peak as I angled north to cross the Palmer Divide and, as if on cue, dropped behind the Front Range when I entered Metro Denver. What better companion to make this ritual drive more inspiring!

Kansas Sunset

Central Kansas is not known for its scenic landscape. There are no mountain vistas, rugged seascapes or large, braided rivers. Semiarid and rather flat, the only topographic relief is provided by low, distant tablelands, carved from the plains by modest streams.

But yesterday evening, as I approached Salina, a spectacular sunset unfolded across the western horizon. Near the setting sun, the sky was ablaze with gold while a kaleidoscope of reds, purples, oranges and pinks painted the flat clouds that partially obscured a pale, blue sky. The broad vista, typical of the Plains, produced an awe-inspiring event, covering the western half of my panorama. Laced with contrails, the colors changed constantly as the sun dipped further below the horizon, producing a flux in lighting and shadows.

Travel and nature study teach us that all ecosystems possess interesting and inspiring traits. What the Great Plains may lack in topography is more than balanced by the beauty of their grasslands and the grandeur of their Big Sky.

Sunday, January 18, 2009

Conserving our Home Planet

Though I've never been a fan of science fiction, it is interesting to contemplate the presence of civilizations on other planets and in other galaxies; indeed, it is a mathematical certainty that they exist. Nevertheless, even if we could travel at the speed of light, it would take humans more than a lifetime to reach what is likely our closest inhabitable planet.

Meanwhile, scientists focused on space exploration talk about sending astronauts to Mars which, they propose, we might colonize some day (especially if Earth becomes uninhabitable). While the space station, space probes and, perhaps, an outpost on the moon make sense from a scientific point of view, the push to send man to Mars will divert funds that might otherwise be used to improve living conditions on Earth. In my opinion, it is better to direct research toward the development of pollution free energy systems and other projects that protect the natural environment of our home planet. Combined with efforts to control the human population, such a focus will, in the long run, be more beneficial to humans (and other life forms on this planet) than will a race to inhabit Mars.

Earth is, after all, our natural home. Diverting funds from the conservation of this planet in order to occupy another makes little sense. I'd rather go down with the Earth than live in a dome on Mars.

Saturday, January 17, 2009

Wildlife in Winter

Wild creatures adapt to winter in a variety of ways, depending upon their metabolism, food requirements and natural insulation. Once the first freeze of autumn descends on the Heartland, most adult insects die off, their species sustained in the form of eggs, pupae and larvae (aquatic or terrestrial). Some species (certain bees, harvestmen, ladybird beetles) overwinter as adults, retreating to protected sites (hives, dens, buildings, leaf litter, mulch piles).

Amphibians and turtles spend the winter buried in soil or pond muck while snakes and lizards retreat to underground dens. Birds, having both mobility and natural insulation, make choices based on their food requirements. Those that feed on flying insects and nectar migrate to southern climes while most seed and berry lovers manage just fine in the Temperate Zone winter; nevertheless, some of these hardy species move to lower elevations or roam about to escape heavy snows. Some birds, known as irruptives, invade the Midwest on an erratic basis, driven south by food shortages (nuts, berries, lemmings) in their northern habitats.

Mammals adapt to winter in a number of ways. Some (bats, ground squirrels, woodchucks, marmots and most bears) hibernate through the lean months, nourished by a layer of brown fat. Others (tree squirrels, chipmunks, pikas, muskrats, beaver) survive the winter by feeding on stored food supplies. Large herbivores (elk, caribou, bighorn sheep, moose) either migrate to sheltered areas or change their diet to more accessible vegetation; they are, of course, followed by the wolves, coyotes and mountain lions that prey on them. Smaller mammals (raccoons, opossums, cottontails, mice) may den up during periods of extreme winter weather but must become opportunists to survive, taking what nature provides (or what man discards).

Friday, January 16, 2009

The Burden of Miracles

A school is leveled by an earthquake, killing dozens of children; two days later, a child is pulled from the rubble with no apparent injuries. A team bus collides with a truck and all are killed except for a young man who is thrown from the vehicle, surviving without a scratch. And yesterday, a passenger jet collides with a flock of birds, loses engine power but safely lands on the Hudson River; all crew and passengers survive without serious injuries.

Religious people refer to such events as miracles, seeing the hand of God in the protection of those that survive. Of course, they never explain why God allowed the earthquake or accident to occur in the first place or blame him for any suffering or death that resulted from the event. They are reluctant to accept the fact that luck and happenstance often govern our lives and, in the case of yesterday's accident, tend to minimize the role that skill, training and safety procedures played in the fortunate outcome.

Miracles are illusions of the primed human brain, offering reassur-ance that God is there to protect us from harm. Unfortunately, such beliefs impose a heavy burden on survivors, many of whom feel (or are told) that they were saved for a reason, that they are destined to play a significant role in God's plan. Such expectations can produce feelings of inadequacy, leading to depression, anxiety and, in some cases, suicide. Miracles are best relegated to our mystical past.

Thursday, January 15, 2009

A Window on Winter

Every day, whether I'm at home, at work or on vacation, I spend some period of time watching the natural world. I do this for enjoyment and for the calming effect that it has on my system. Nature, oblivious to human turmoil, moves at her own pace.

Whether the view is limited to my back yard or extends across a mountain valley, the effect is usually the same. One never knows what will occur during these interludes. Perhaps an unusual beetle will settle on the railing or a red fox will cross the meadow; a flock of waxwings may appear in the shade tree or the crack of a rock fall may thunder through the canyon.

Today's view is from my office window, facing westward from the School of Medicine; a paved lot, utility building and parking deck occupy much of the foreground, backed by a wooded residential area in south Columbia. The clear, cold sky is deep blue except for a shelf of clouds far to the southwest, likely the trailing edge of the Arctic dome that has settled over the Midwest. Humans, ill equipped for this frigid weather (currently 9 degrees F), move quickly between the buildings save a lone smoker, finishing his cigarette behind a stand of white pines. Birds, usually well represented in my broad vista, are limited to a cloud of starlings that settled in a barren tree down the block. No surprises today; just a brief respite on what may turn out to be the coldest day of the season.

Wednesday, January 14, 2009

Zero!

Tonight, for the first time this season, the low temperature is forecast to reach zero F in Columbia. For many Americans, still focused on the Fahrenheit scale, this temperature marks a significant and worrisome barrier, below which we enter a perilous world.

While few would deny that zero degrees F is, indeed, cold, it is, in fact, just another unit above absolute zero, the theoretical point at which atomic movement comes to a halt. The latter sits near minus 460 degrees F; the lowest temperature ever recorded in nature (Antarctica) was minus 128 degrees F, while the highest (in Libya) was near 136 degrees F. Both the universal Celsius scale and the provincial (primarily U.S.) Fahrenheit scale are human devised measurements, based on differing units between the freezing and boiling points of water (0 and 100 degrees for Celsius, 32 and 212 degrees for Fahrenheit). Too often, TV meteorologists comment that it is twice as warm or twice as cold in one city than it is in another; while this may be true on the artificial human scale (e.g. 40 degrees F in Denver, 80 degrees F in Miami), the true measure of heat (above absolute zero) would be 500 vs. 540 Fahrenheit degrees.

So tomorrow morning, as we try to start the car at zero degrees F, we might feel better to know that it is actually 460 degrees above absolute zero!

Tuesday, January 13, 2009

Trouble in Paradise

In the midst of a cold, snowy winter, many Americans dream of an escape to Hawaii, our 50th State and the land of perpetual summer. Blessed with a mild, stable climate, beautiful scenery and spectacular seascapes, the residents of that island chain need only deal with occasional heavy rains, wayward hurricanes and, on the Big Island, the threat of volcanic eruptions and lava flows.

But this week, the northern beaches of this tropical archipelago will be raked by massive waves, courtesy of a potent storm in the North Pacific. Moving slowly to the east, the storm has generated strong, northwest winds, which have stabilized near 60 mph; these winds produce large swells over the open ocean, which, in this case, are moving off to the southeast. The Hawaiian Islands are directly in their path and waves of 20-35 feet are expected along the north and west facing beaches.

A godsend for surfers, the waves may prove to be destructive in some areas. Of course, those Americans shoveling ice and snow in sub-zero temperatures may find it hard to be sympathetic!

Monday, January 12, 2009

Man's Short Memory

Humans, as individuals and as a species, have short memories. Our cycles of war, economic turmoil, political corruption and religious scandal attest to this trait. So too do the "natural disasters" that plague our societies, many of which are preventable.

A few years after Katrina, there is pressure to rebuild on land below sea level, relying on better levees to protect the region. A decade after the Great Flood of 1993, towns reappear on the Mississippi floodplain, determined to survive. Across the globe, we settle on steep hillsides, invade fire-prone areas, occupy barrier islands and even construct our own islands in the sea. At the same time, we level forests, drain wetlands, irrigate deserts and plow up prairies, oblivious to the consequences.

Of course, the ever increasing human population is the primary engine behind many of these practices but our short life span, devoid of perspective, is also a significant factor. We feel immune to the natural and human disasters that have shaped our planet and our civilization. And when it comes to our own impact, we forget the past and ignore the future.

Sunday, January 11, 2009

Out of Alaska

The jet stream pattern that brought flooding rains and heavy snows to the Pacific Northwest for the past two weeks isolated a dome of high pressure over Alaska. Sitting in the perpetual darkness of the northern winter and cut off from any southerly winds, this pocket of air became increasingly cold, with regional temperatures down to 40-50 degrees (F) below zero.

Now, the jet stream has shifted, pushing a ridge of high pressure up from the south and nudging the frigid, Alaskan dome to the east; as a trough develops on the east side of the ridge, this extremely cold air will plunge toward the southeast, bringing the lowest temperatures of the season to the Northern Plains and Upper Midwest. Moderating as it pushes southward, the cold front will produce dramatic cooling over almost all of the eastern U.S., including northern Florida.

Such events remind us that weather patterns in our atmosphere, governed by the jet streams, are rarely stable. Ridges form and break down; troughs plunge and then retreat. This week, Alaska's recovery is at the expense of eastern North America.

Saturday, January 10, 2009

The E.D. Epidemic

Anyone who watches American television for more than an hour or two would think that erectile dysfunction is the most pressing health problem in the U.S. Several pharmaceutical companies, vying for the lucrative market that these drugs target, shower the airways with images of happy couples, their relationship sustained by one of these expensive products.

While there are legitimate medical conditions that warrant the prescription of these medications, the excessive advertising is a clue that the drug corporations have a wider audience in mind. Though the commercials focus on the lasting sexual relationship of middle age couples, it is clear that the media blitz is directed primarily at older men with younger partners: mistresses or second wives. In addition, the appropriate warning regarding "erections lasting more than four hours" is a clever hook to lure younger men who have doubts about their sexual prowess (which also explains the spam emails offering access to these drugs).

Though drug companies certainly have the right to advertise their products and to make profits, it is a sad commentary on American society that the E.D. commercials soak up airtime that could be used for more significant, widespread health issues. Once again, the message is that we have a drug for all of our problems; in this case, it also provides insight into the nature of male sexuality.

Friday, January 9, 2009

Cumberland Gap

Cumberland Gap, once traversed by the Indian Warrior Path, became a famous conduit for the Wilderness Road when Daniel Boone and his party entered Kentucky in 1769. Today, protected within a National Historic Park, this deep notch in Cumberland Mountain is the centerpiece of a natural area that offers a pleasing mix of history, scenery and outdoor recreation.

Nine hundred feet deep, the Gap was once thought to have been created by wind. We now know that it was carved by a stream that flowed southward to join the Powell River; in more recent times, this stream was "captured" by Yellow Creek, diverting its flow northward to the Cumberland River. Cumberland Mountain, which parallels Pine Mountain to its north, represents the barrier between the Appalachian Plateau (to its northwest) and the Ridge and Valley Province (to its southeast); the crest of this long, narrow ridge forms the border between Kentucky and Virginia northeast of the Gap.

A visitor center, in Middlesboro, Kentucky, introduces visitors to the natural and human history of the region and provides maps for hiking trails that climb onto Cumberland Mountain or run atop its summit; one of these leads to the Tristate Pavilion, at the junction of Kentucky, Virginia and Tennessee. Those less inclined or unable to hike the trails can take a short drive up to Pinnacle Overlook, just northeast of the Gap, which provides a spectacular panorama of the surrounding landscape.

Thursday, January 8, 2009

Intelligence and Evolution

Until the evolution of man, all species on Earth had been confined by their physical traits. Over time, natural selection dictated the diversity of our planet, as species that adapted to the environment survived while those that could not became extinct. A species faced with a changing climate, dwindling food supply or increased competition, either evolved traits that favored its survival or succumbed to the advance of other life forms. Such events, unfolding over thousands or millions of years, allowed cetaceans to return to the sea, birds to take flight and well-insulated creatures to inhabit the colder regions of our globe.

But man, endowed with a large brain, did not have to wait for evolution to supply his needs. Intelligent enough to build shelters, control fire and create protective clothing, he spread across the continents, eventually learning to construct boats, domesticate animals and cultivate plants. His brain power would lead to scientific breakthroughs, the industrial revolution and, perhaps too late, the environmental movement. He did not need to evolve fins to cross the oceans, develop wings to fly or grow a thick fur coat to survive the winter months.

Freed from the confines of evolution, we have "conquered the globe" and, at the same time, have begun to destroy it. Whether our intelligence will finally produce a peaceful, pollution-free, self-sustaining planet is yet to be seen. Unfortunately, many cultural, religious and psychological barriers must first become extinct.

Wednesday, January 7, 2009

Winter Birding

Winter may not be the most pleasant time for birding but it generally brings more rare sightings than any other season. Vagrants, irruptives and weather-dependent migrants promise new life-list species for birders throughout the Heartland.

Our large reservoirs often attract rare loons (Pacific, yellow-billed, red-throated), jaegers (parasitic, pomarine), gulls (Thayer's, glaucous, lesser and greater black-backed), scoters (black, surf, white-winged), oldsquaws and Barrow's goldeneyes. Out on the grasslands, we have the chance to encounter snowy owls, common redpolls, snow buntings or longspurs. Even residential areas might attract Bohemian waxwings, crossbills or evening grosbeaks.

It is the prospect of such discoveries that draws passionate birdwatchers into the bleak landscape of a Midwestern winter. After all, these species won't hang around for those warm, spring field trips!

Tuesday, January 6, 2009

The Tree of Evolution

The history of life on Earth can be visualized as a massive, branching tree which germinated 3.6 billion years ago. Mediated by genes and governed by natural selection, each branch of the tree represents a new species; some of these branches never advance beyond a twig while others become thick trunks, giving rise to many more species over the eons.

Mammals branched from reptiles about 200 million years ago (MYA) and primates branched from the mammalian line some 60 MYA. Apes split from other primates at least 15 MYA and hominids diverged from the chimp line about 7 MYA. Finally, modern man evolved from ancestral hominids just 125,000 years ago. Our species would thus be represented by a short twig on the periphery of this massive tree of evolution; whether that twig will die out, persist in isolation or eventually branch into other species is a matter of speculation.

Only natural species, which include man, belong on this tree. Those domestic animals and cultivated plants that have been engineered by man are not natural; they represent some of the many ways in which humans have manipulated nature and most could not survive without man's nurturing and assistance.

Monday, January 5, 2009

The Arctic Shark

Of the many sharks that roam our oceans, only a few enter the Polar regions; of these, only the Greenland shark is known to permanently inhabit the Arctic Sea. Found across the North Atlantic, from northern Europe to Canada, this shark feeds at great depths (down 2000 feet or more) for most of the year, ascending to shallower water during the winter months.

Rivaling the size of a Great White, the Greenland shark has long been hunted for its liver oil and meat; however, the latter harbors a neurotoxin and must be boiled several times and then dried before eating. Human hunters, noticing its rather docile nature during capture, inspired the common title of "sleeper shark" for this largest member of the dogfish family. Nevertheless, it appears to be capable of catching agile fish, belugas, narwhals and seals; it has also been known to feed on polar bears and caribou, perhaps nabbing them as they cross open water. Of special interest is the susceptibility of these sharks to parasitic copepods, which attach to their corneas; past theories that these parasites aided the shark by attracting prey have not been confirmed.

So, if you're dreading two more months of winter and have begun to feel sorry for yourself, just think of the Greenland shark. You could be swimming in the cold, dark waters of the North Atlantic, with a copepod attached to each eye!

Sunday, January 4, 2009

A Touch of April

It may have looked like winter in mid Missouri yesterday but it sure felt like spring. Down at the Forum Nature Area, the trees were bare, the grass was brown and the sky was gray. A mix of sparrows and juncos foraged along the trails, small flocks of waterfowl dabbled in the shallows and a lone red-tail circled overhead. The only spring-like color was provided by an occasional cardinal and by a group of eastern bluebirds, perched on a power line.

But a warm, moist air mass had moved into the State and afternoon temperatures hovered in the low sixties. One could almost hear the tree frogs, gearing up for a long spring. And, of course, the mild conditions brought out hordes of humans, those pampered mammals that usually hibernate during the winter months.

As usual, this hint of spring in January was a harbinger of coming change, produced by a southerly flow ahead of the next cold front. The latter arrived overnight and we'll stay in the twenties today. The Midwest roller coaster remains on track!

Saturday, January 3, 2009

The Winter Wren

Mention "wren" and most Americans will think of a small, brownish, noisy bird that flits among their shrubs and woodpile during the warmer months. Of course, this would be the house wren, a common summer resident throughout much of the U.S. But its cousin, the winter wren, is less common and far less conspicuous.

This tiny bird breeds across Canada, the Great Lakes region, New England and down through the Appalachians, wintering in the Midwest, Southeast and along the Pacific Coast. Smaller than the house wren, it has a plump figure, accentuated by a short bill and very short tail. Despite its diminutive stature, the winter wren is known for its loud, clear, high pitched trills, which are often the only clue to the presence of this reclusive winter visitor.

Usually alone during the colder months, the winter wren is best found in thickets or dense tangles along ravines or stream beds. There it finds insects, snails and other small invertebrates on which to survive the lean season. Come late March, this hardy bird will depart for northern breeding grounds where it favors the understory of coniferous woodlands.

Friday, January 2, 2009

The Age of Man

Though humans appeared 125,000 years ago, we were just another mammal species for much of our history, traveling and camping in small groups, hunters as well as potential prey. Then, about 15-20,000 years ago, man began to establish permanent settlements, followed by the development of trade routes, the domestication of animals and the cultivation of plants.

These towns and cities fostered innovation and, over time, the advance of science, industry and technology. As a consequence, our species began to take an increasing toll on natural ecosystems and on the global environment. Habitat destruction, pollution, warfare and the depletion of natural resources began to threaten the fragile balance of life on this planet. Over the past few decades, the environmental movement has begun to counter these effects but the threats imposed by an ever increasing human population remain significant.

How and when will the Age of Man come to an end? Potential scenarios include a natural catastrophe (asteroid strike, super volcanic explosion), the irreversible poisoning of our water and air, nuclear war, a lethal epidemic or the exhaustion of Earth's resources. Should man become extinct (or depart for another planet) before the sun dies, most other life forms will likely have succumbed to the tragic events, leaving bacteria, algae and other primitive species to ignite another sequence of evolution.

Thursday, January 1, 2009

Natural Weight Loss

Of all the New Year's resolutions, whether expressed, written or merely contemplated, the commitment to lose weight is surely the most common. Unfortunately, many of these hopeful individuals will turn to restrictive, expensive or fad diets to accomplish their goal. But, if they are truly committed and have the support of family and friends, the following recommendations will bring success.

Eat three balanced meals each day; skipping meals will just encourage the consumption of unhealthy, high-calorie snacks. Decline second helpings and do not eat fried or sugar-sweetened foods. The intake of at least two servings of fruit each day will provide important nutrients and help to eliminate any craving for sweets. Between meals, consume nothing but water or calorie free drinks; restrict alcohol intake to no more than three drinks each week. Finally, with regard to food intake, treat yourself to one dessert each week.

Of course, calorie restriction and healthy food consumption are only part of the solution. Plan to walk one mile each day (in addition to whatever walking you do at work or in your daily chores); over time, gradually increase the distance that you cover. In addition, unless limited by health or physical conditions, bypass the elevator and take the stairs for any distance less than four floors. The combination of these activities and the above dietary recommendations will produce weight loss at a gradual, healthy rate and will likely induce other beneficial lifestyle changes.

Best wishes for a healthy and Happy New Year!