Saturday 4 October 2014

Midwest Natural History

Various skeletons representative of the Ice Age fauna grace the halls of the Chicago Field Museum.
I’ve only visited the state of Indiana once in my life—and that for ten weeks. Due to the length of my stay and the nature of my travels, I felt sufficiently acquainted with the land to deeply contemplate it’s past. Usually I reserve such intimate deliberations for moments when a warm campfire casts reflections on my eyes, and certainly I was able to experience that in Indiana. But I think it is the broad connection of the region to other areas like Wisconsin and Minnesota that prompted a feeling of liberty to delve into the region’s dark past.
My purpose in the Midwest this summer was not one of lay apathy and leisure; rather, I had come to assist the University of Notre Dame in their brave attempts to reduce the human impact on the North American Continent. Everything in nature is interconnected in some way, including human society. Ecologists like Gary Lamberti, David Lodge, and Jennifer Tank have long recognized such interrelation among living things and places and it was my pleasure to work with them as an intern. The changes they were able to initiate through their efforts are certainly worthy of recognition.
Between accompanying the virtuous members of Dr. Tank’s lab on field trips and the outings of the students into the surrounding countryside, I was soon becoming reacquainted with familiar faces from my last visit to the Midwest, some four years ago. Between my duties as a stream ecologist, I went wading through the wetlands, spying on the turtles, teasing hog-nosed snakes, and bird watching on Lake Michigan’s cobblestone shore. The call of Cardinalis flooded my mind with nostalgia; summer days at Grandma’s house in Wisconsin. A slough near the campground where I was staying rang with the breaking strings of a multitude of banjos: Rana clamitans. I spent hours roaming the lakeshore for those amphibians as a child. However, I really began to contemplate the history of the land, the geological shifts and ecological transfers over time, when I visited the Field Museum in Chicago.
The museum itself had dedicated nearly an entire floor to Earth’s history. The halls were adorned with spectacular examples of Charles R. Knight’s paintings and mounted skeletons and model dinosaurs brought the exhibits vividly alive in my imagination. However, the entire exhibit had been constructed with an atheistic mindset. One exhibit read, “See what 50 million years of evolution can do.” I looked, but couldn’t see what 50 million years of evolution had done.
Naturally, the Christian naturalist is skeptical of popular thinking in science. After all, most of the information researched and portrayed in secular, public institutions is performed from a godless perspective. Fortunately, Christian’s are of an older sort of naturalist—before Mr. Darwin—inclined to praise the Creator for his handiwork. It is unconventional, but it hones the evidence into a manageable form, closer to truth. But I digress.
Looking up into the massive head and jaws of Sue the Tyrannosaurus rex at the Field Museum, I couldn’t help but envisage what sort of ecological succession had taken place in the state. Of course, on a Biblical timeline, fossils likely only fall into one of two categories; those formed during the global flood described in Genesis 6-9 or after it. I was surprised to discover that the only fossils in Indiana that seem to be from a time before the global flood are reflective of marine sediments, primarily invertebrates, their shells preserved in the limestone.
It is hard to say exactly what the midwestern part of North America, part of a supercontinent at that time, was like before the flood. After all, there is such a diversity of ecosystems preserved around the world, and the distributing affect of the floodwaters so poorly understood by anyone, all one can say with any confidence is that those fossilized organisms really did live on the biosphere at some point in the past. Obviously, I need to put a whole lot more thought into the topic of sedimentology if I want to get an accurate picture of the world before the flood. As to what happened after the flood, a more detailed story emerges.
The Midwest really only become the Midwest after the flood. Before that, North America didn’t exist as a continent, more than likely. The flood left Indiana and the rest of the planet stripped of life. It would have been a very alien looking world. Using evidences seen around the continent today, the change that underwent in the Midwest over the last 4000 years can be catalogued with some accuracy:
Barren ground stretched as far as the eye could see. From space, the grey earth looked something like it does today—but not exactly. The continents were slightly ajar and their cores were littered with giant lakes. A particularly massive body of water loomed near present day Arizona. East of the Rocky Mountains, alive with the smoke of volcanic unrest, the sky would have reflected on the giant lakes dotting the place we would one day call the Great Plains. About 4,400 years ago, it looked more like the Great Lakes were a worldwide feature. But those particular lakes didn’t appear to be on North America’s face at all.
The air of this empty earth was absurdly humid. The sky was darkened with moisture and ash from spastic volcanoes. However, the life God created to inhabit this earth is tenacious. Within the first year, green smears appeared. By around 4,300 years ago, full communities of plants were flourishing and some of the smaller, more prolific creatures had been spreading out from the Middle East.
But North America wasn’t devoid of animal life, even at this early stage. The storms raging around the globe reflected on the recently violent past, but amid the tossing waives of those early lakes a flash of silver appeared in the water. Some intrepid creatures survived the brutality of the global disaster that raked the world of life. Adapted to aquatic lifestyles, a variety of fish were stranded in dark, muddy pools across America. These warm, humid environments took on a shape more like the African Congo than temperate America, as the plant and animal communities adapted.
In a moist swath of land from the Midwest to the coasts of Washington and British Columbia, the abundance of lakes produced a lush forest. Some of the first colonizers, like the fish trapped in the lakes by receding waters, would have been familiar to Americans. Gar, bowfin, perch, sunfish, and catfish species witnessed the arrival of land animals, moving in from Europe and Asia via a land bridge across Greenland. Aquatic invertebrates also survived the global flood, with many species of worms, clam, and snail beginning to flourish in the lakes. Unfortunately, many of these pioneers never made it into the present. Skates went extinct in North America, even after they’d survived the global flood.
Not surprisingly, insects took hold of the new land quickly. Turning over a log or walking near a streamside in what would one day become Washington would reveal a micro-community essentially the same as those today, including spiders, dragonflies, damselflies, grasshoppers, beetles, mosquitos, butterflies, moths, wasps, bees, ants, and many other familiar faces. The air was alive with the buzz of countless insects. Frogs, salamanders, crocodiles, lizards, and snakes moved into their perspective ecological niches as well, but most of these were species unfamiliar to us. Turtles, in particular, flourished in the ideal lake-riddled habitat. Birds weren’t as common as some of the smaller, more adaptable creatures, but flamingos, owls, hawks, cuckoos, rails, and curlews found the new watery world to their liking. There were a few stranger birds as well, like the six-foot tall, mega-beaked bird Gastornis.
While some of these scaly and feathery creatures lived on in other parts of North America, the mammalian fauna was nearly completely unique. Brontotheres, massive tusked ungulates with heads ornamented in horns and growths, soon arrived to rule as the largest animals of their day. Many other strange hooved creatures, like tapirs, also stepped lightly through the forests. The most common predators were the creodonts, a diverse group of mammals that, thanks to their ability to spread and diversify rapidly, filled the ecological niche of the carnivores we see today. Unfortunately, as time progressed, these lakes began to drain and dry. The shifting unrest of the continental shelves made life difficult. Eventually, nearly the entire fauna died out and their ecological niches were replaced, as the land grew more open.
            With the disappearance of the first colonizers, more familiar faces began to take a hold in the drying lake belt. True carnivores, like cats and dogs, replaced the dwindling creodonts. Horses, camels, and rodents replaced the more bizarre tropical creatures of earlier days. However, the pig-like oreodonts, sometimes called “ruminating hogs,” proved more tenacious, living alongside their more modern neighbors before any large grazers moved to replace them.
A little farther south in the lake belt, little three-toed horses grazed alongside a variety of small rhino and camel species and burrow-digging land beavers occupied before the days of prairie dogs. The monstrous entelodonts, like overgrown, steroidal warthogs, terrorized the smaller animals with their looks, if nothing else. Before long, horses had diversified into about a half dozen genera and camels and deer were keeping up as new habitats opened the door for new species. One deer even had saber teeth, its relatives living on in Asia today. The strange bear-dogs, which looked as their name suggests, hunted many of the herbivores. Among the birds taking advantage to the more open landscape were crowned cranes and secretary birds, both now limited to Africa. At 4,200 years ago, the Serengeti had come to America.
In reality, the Midwest was far overdue for a shift to more contemporary faunal styles. The eastern coast already had a good community of baleen and toothed whales. The southeast had alligators, already developing into forms that looked much like their modern counterparts. Other reptiles included familiar snake families and turtles so like those living in the east today that they have been given the same names: painted turtles, box turtles, snapping turtles, and sliders. Among mammals, shrews, moles, weasels, badgers, rabbits, and rodents had already made themselves at home alongside the stranger camels, horses, tapirs, rhinos, peccaries, and sloths.
Larger new arrivals appeared in the south, discreetly migrating down from the northern land bridge, apparently. Saber-toothed cats, shovel-tusked elephants, and short-faced bears were a foreshadowing of days to come when things would get even larger.
As massive eruptions of the restless earth continued to influence constant succession of ecological communities, the west was soon following suit to the east. Raccoons, cats, dogs, and pronghorn antelope joined the dwindling members of the older inhabitants. Mastodons and beavers quickly joined the train, outnumbering the old warm-weather creatures, and no wonder; the climate was cooling. Trees on the growing plains were switching over to classics of temperate conditions. Oaks, sycamores, maples, gingkoes, and elms dotted the plains. Many would remain staples of North America into the future.
Something big was coming. The land had grown dry. The humidity and warmth were fleeing southward. Lakes shrunk and dried into desert basins. Water had faded from the land—but the ocean didn’t rise. The water was building up somewhere else.
The global flood had created an environmental time bomb. All the humidity and moisture in the air following the flood had given the world the false impression that things would return to the warm tropical climate of ancient times. However, all the volcanic activity caused by shifting continents during and after the flood had filled the atmosphere with debris and suspended water. The hazy skies were a warning that the sun was not able to do the warming prescribed to it. The moisture was finally falling, but not as rain on parched plains. Snow was turning Canada white.
As the world began cooling more quickly, mastodons increased their range and more modern varieties of horse and camel replaced the little three-toed species. Voles, beavers, and other modern rodents became mainstream. Carnivores, like the bone-crushing dogs and dirk tooth cats, completely replaced creodonts and other ancient carnivores. In the Midwest specifically the mammals were still strange to modern faunas, including rhinos, dogs, short-faced bears, and peccaries, the smaller inhabitants of the modern Midwest, like leopard frogs, had basically been established.
Along the coasts, as far south as Baja California, walruses and fur seals were hulling up on the beaches. By 4000 years ago, the Ice Age was in full swing. Unfortunately, the impenetrable glaciation of the north swept down into the Midwest and prohibited Ice Age life from inhabiting the barren white sheets of ice. However, there were some pockets, caused by hot springs and geography, were Ice Age creatures found a foothold. As always, the invertebrates held on through the cold. Clams, snails, and slugs moved slowly around pools of warm water emanating from the springs. Some smaller animals like mink, ferrets, prairie dogs, voles, moles, coyotes, wolves, camels, oxen, and lamas populated the shrubbery, but glaciers weren’t the only giants of this time. Megafauna ruled as the aptly named colossuses of the interglacial plains. Giant short-faced bears, over twelve feet tall, took advantage of weaker animals as two species of mammoths aggregated by waterholes.
When the earth finally returned to a more normal climate, the Midwest was restored to open plains. Interestingly, it wasn’t kept that way by purely natural causes. As trees started to encroach on the plains, some creatures found their preferred prey becoming more rare, moving west. One species in particular would not stand by to watch the plains encroached upon. It was the first time the environment in North America was impacted by humans. They started fires on purpose.
Over the years, new cultures infiltrated the Americas. As megafauna died off, early Americans developed new ways of life. Distinct tribes of people began to become established around 3500 years ago and 500 years later, people, divvied up into various territories, occupied the whole continent. Megafauna, with the exception of bison, grizzlies, and a few others, went extinct from the increased territorial pressure. Around 2000 years ago, most of the tribes that early explorers would encounter had formed. While farming in the Americas started nearly 3000 years before European settlers arrived, the Midwest natives’ farming of land probably didn’t start until only 1500 years before westerners saw corn for the first time. But when they did, around 500 years ago, the newfound food was irresistible. Within a mere 350 years or so, the entire Midwest, with the exception of a few pockets, had been engulfed in western culture’s insatiable appetite.
Naturally, I feel fairly strongly that mankind’s negative effect on the natural history of the Midwest should be reversed, but there seems to be little chance of that happening anytime soon. Extinction and change, even man-made change, have been a part of our changing planet since the beginning. In essence, anything negative that happens to nature is directly or indirectly caused by the evil of humanity. After all it was Adam’s sin that brought a curse on nature, and it was mankind’s wickedness that brought the global flood. Not surprisingly, sin is again become very commonplace in our culture. Lets be careful that we don’t execute God’s judgment for him through abuse of the planet.

2 comments:

  1. Hi Caleb, well written article. Although I do have trouble when you call humans a species, they are totally different than the animals; made in Gods image. dad

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    1. Thanks for the comment Dad. I certainly wouldn't deny mankind's status as God's special creation, in his image. When I refer to humans as being species, I only mean that they, like any other living thing, have been classified with a genus and species. It's a manmade system that I'm referring too. Hopefully I can find the time to write about the difference between humans and animals in the future.

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