Keystone of the Savanna

Last year I wrote this paper for the class Archaeology of Wisconsin. It’s basically the background premise for my dissertation, and will end up in some form in the first chapter.

Keystone of the Savanna: Humans and the Evolution of Midwestern Holocene Ecosystems

Abstract:

At the time of nineteenth century Euro-American settlement, the American Midwest consisted of diverse, functional, and productive savanna ecosystems. Prairie grasses, flowers and shrubs carpeted the earth beneath and between widely-spaced groves of open-grown nut-producing trees such as oak, hickory, chestnut, and walnut. For nearly 10,000 years, these savannas supported a diversity of plants, animals, and human cultures, many of which are now endangered or extinct. To fully appreciate the history, ecology, and evolution of these ecosystems, I argue it is critical to include the story of the peoples who once inhabited the savanna: people who were not just passive inhabitants, but keystone species. Through their burning, hunting, gathering, and horticulture, Aboriginal Americans helped shape and maintain the structure and function of Midwestern ecosystems. This paper will review and analyze archaeological, anthropological, historical, and ecological literature in order to tell a story of an ecosystem and the people who shaped it – the keystones of the savanna.

A Brief Ecological and Human History of Eastern North America

This paper is focused on the unique temperate savanna ecosystems that evolved in Midwestern North America during the Holocene, the geologic epoch of the last 10,000 years since the ice age. The region that once supported these ecosystems extends in a broad arc across the Midcontinent from Southern Canada to Texas in what ecologists refer to as the “Eastern prairie/forest transition” (Curtis 1959; Anderson 1983; Nuzzo 1986), and I’ll focus more specifically on the  “prairie peninsula” region of the Upper Midwest (Transeau 1935). I use the word “savanna” generally to describe grasslands with scattered trees. Inclusively defined, I consider savanna, to encompass a variety of states ranging in tree cover density from widely spaced open-grown “openings” and “parklands” to nearly continuously canopied “open woodlands.” The unifying factor is the continuous groundlayer of grasses often diversely assembled at varying densities alongside flowers, legumes, and shrubs, underneath and between the trees.

Paleoindians in Pleistocene savannas

Pleistocene North America consisted largely of savanna ecosystems for at least the last 10 million years (Axelrod 1985). Large herbivorous mammals consumed and trampled massive quantities of woody vegetation, creating a dynamic mosaic of open grassy and wooded patches. In a closed forests, not enough sunlight reaches the floor to support grasses. These manufactured savannas with mixes of wooded and grassy areas, supported browsers and grazers alike promoting habitat and species diversity at multiple scales (Owen-Smith 1988). Mammoths, Ground Sloths, and Giant Beavers helped shape spruce savannas of northern latitudes, while mastodons, proboscidea, camels, and horses shaped the oak and pine savannas of southern North America and Central America (Owen-Smith 1988). These megafauna were keystone species (Paine 1969) whose behavior disproportionately influenced ecosystem structure and function.

As the glaciers of the last ice age began melting at the end of the Pleistocene, a culture of Paleoindian peoples archaeologists refer to as, “Clovis,” rapidly colonized the warming Americas. Mobile family bands exploited the immense quantity and diversity of large mammals that had evolved here in the absence of humans. These animals were hunted and processed with weapons and tools from a unique and widely-shared toolkit (Stoltman and Barreis 1983). By the end of the glacial retreat a few thousand years later, Pleistocene megafauna were extinct. Most scholars today recognize both human hunting and climate change as significant drivers of these extinctions (Barnosky et al. 2004; Gill et al. 2009; Lorenzen et al. 2011). Regardless of the cause, however, this extinction event had drastic consequences for the ecosystems of North America and the peoples that would make a permanent home here.

Archaic and the Holocene savanna

In the absence of mega-herbivore grazing and browsing, forests rapidly replaced savannas in an instance of what ecologists refer to as “ecological release.” One major consequence was the simplification of fine-scale savanna mosaic ecosystems into broad-scale zonal vegetation leading to further species loss (Owen-Smith 1988; Johnson 2009). In general, forests flourished in the Eastern U.S., while grasslands spread in the more arid West (Axelrod 1985). In between the forest and grassland biomes, was the prairie-forest transition zone (Curtis 1959; Anderson 1983; Nuzzo 1986). This is where Midwestern Holocene savannas formed 8-9,000 years ago, when a dryer climate with increased seasonality led to the migration of oak and hickory from the south and prairie vegetation from the west (Gleason 1922; Winkler et al. 1986). This climate was conducive to frequent fires, favoring the fire-adapted grasses, flowers, and oaks we now identify as the oak savanna.

Midwestern Holocene savannas were highly diverse and productive through complimentary combinations of organisms and processes from their grassland and forest counterparts. The continuous ground-layer of grasses and flowers provides forage for bison, elk, and deer, seeds and roots for small mammals and birds, and nectar for insects. Shrubs such as hazelnut and plum provide habitat structure for birds, small mammals, and insects, vegetation for deer and elk, and high-quality fruits and nuts for mammals and birds. Oak and hickory trees provide habitat for birds and insects and immense quantities of high-quality nuts for many birds and mammals, including humans. It was here that Paleoindian peoples, no longer able to follow and hunt large Pleistocene mammals, settled into more local ecosystems, utilizing a much more diverse set of relatively immobile plants and smaller animals (Stoltman and Barreis 1983; Bonnicksen 2000; Delcourt and Delcourt 2004).

Archaeologists recognize several distinct successive cultural traditions in North America based on differences in patterns of persistent inorganic materials such as pottery and stone tools present in their excavations. The Archaic tradition immediately followed the demise of Clovis, and lasted from 8,000 to 3,000 years ago (Stoltman 1997). A number of significant cultural trends, technologies, and adaptations took place in this period. Communities were able to sustain themselves in much smaller territories by scheduling hunting, fishing, and gathering activities to take advantage of times of maximum seasonal availability: summers fishing rivers and lakes, autumns in the upland savannas, and winters in rock shelters hunting deer (Birmingham and Eisenberg 2000). Tools and technologies were developed including stone axes for cutting trees, fishing implements, and stone grinding tools for the bulk processing of acorns and nuts. Increased trade led to regionally integrated economies. Archaeologists have found shells from the Gulf Coast, obsidian from Wyoming, and copper from the Upper Great Lakes appearing in late Archaic contexts (Birmingham and Eisenberg 2000). These are often found associated with increasingly elaborate burial contexts present 3,000 years ago at the end of the Archaic (Theler and Boszhardt 2003).

The development of several new sets of trends, technologies, and adaptations have led archaeologists to recognize a distinct material tradition, the “Woodland.” Traits signifying the transition from Archaic to Woodland include pottery, earthen burial mounds, and plant cultivation,  although each moved into different regions at different rates depending on their perceived desirability (Theler and Boszhardt 2003). Human cultures continued to flourish throughout the Woodland, and the Archaic process of localization continued as peoples increasingly tended gardens of newly domesticated species producing large oily and starchy seeds. Communities became more and more sedentary, although seasonal hunting and gathering remained important. Regionally integrated economies continued to develop in the Midwest culminating in the Hopewell interaction sphere of the Late Woodland (Stoltman and Barreis 1983).

The rise, fall, and ascendancy of agriculture

Fully sedentary cultures did not develop until the “Mississippian” tradition replaced Woodland traditions in the Midwest 1,000 years ago. Mississippians were materially distinct in their use of shell-tempered pottery and heavy reliance on maize agriculture, and culturally distinct in their hierarchic social organization, settlement patterns, and religion (Green, 1997). In parts of the Upper Midwest the “Oneota” tradition developed simultaneously, displaying a mix of Woodland and Mississippian characteristics. Mississippian shell-tempered pottery and maize cultivation were integrated into Woodlandesque egalitarian communities where traditional hunting and gathering activities remained important (Schroeder 2004).

Just prior to fifteenth century European contact, the Mississippian culture collapsed, and much of the Upper Midwest seems to have experienced massive population decline (Green 1993; Milner and Chaplin 2010). Causes of this event remain a mystery, but depopulation and social reorganization continued and accelerated with the waves of European diseases that soon followed, resulting in the tribal systems familiar today. Many tribes including the Siouan-speaking Ho-Chunk and Ioway, and Alogonquan-speaking Ojibwe, Menominee, Fox, Miami, Potowatomi, and Illinois continued to persist in the Upper Midwest until the time Euro-American settlement began in the early nineteenth century. These tribes were semi-sedentary, extensively practicing agriculture, as well as gathering, and engaging on long-distance communal hunts (Brown and Sasso 2001). European newcomers brought a near-death blow to the peoples and the savanna ecosystems that had been co-evolving in the Midwest for nearly 10,000 years.

Armed with steel plows and axes, the first settlers began to farm the savannas. Trees were cut to furnish wood for house construction, fences, and fuel. Fertile soils, packed with organic matter furnished by the growth, death, and burning of countless prairie plants, were plowed and planted with annual grains. By the end of the century, the Upper Midwest would become the Nation’s breadbasket (Cronin 1992). Lands too steep or barren to plow were heavily overgrazed or left alone. Euro-Americans did not use fire as the Indians had, so any uncultivated areas quickly grew up in forest tangle in another example of ecological release (Muir 1913, Curtis 1959).

Nowacki and Abrams (2008) describe this process of transition from open savanna to closed forest as “mesophication.” They define these as two alternative stable states with separate sets of stabilizing feedbacks. The closed canopy of mesic forests keeps the ground dark, wet, and nutrient rich, promoting shade-tolerant, fire-intolerant mesic species. The grasses and leaf litter of savannas provide fuel for frequent low-intensity fires, opening areas and promoting fire-tolerant and shade-intolerant prairie and savanna species. Widespread mesophication occured in the Eastern U.S. following early Indian depopulation, and it has been suggested that this forestation was so significant that the increased carbon sequestration significantly reduced atmospheric carbon dioxide, playing a role in the fifteenth century “little ice age” cooling event (Nevle et al. 2011).

The Midwest savanna had thus been a climatic-vegetation anomaly for the previous 5,000 years when its climate was sufficiently moist to support closed mesic forests (Nowacki and Abrams 2008) as its climax vegetation community (Clements 1916). This anomaly is generally explained by frequent low-intensity fires and although there has been some debate, most ecologists attribute the origin of these fires to the regular burning activities of American Indians (Gleason 1922; Curtis 1959; Anderson 1990). When these fires ceased to burn, Midwestern savannas rapidly converted to mesic forests (Muir 1913; Cottam 1949; Curtis 1959; Nuzzo 1986).

American Indians had become keystone species of the Midwestern savanna, helping to create the very ecosystem that provided their sustenance. So critical were they to the existence of the savanna, that Indian removal immediately precipitated its collapse. While fire was certainly one of the most potent tools utilized by American Indians to shape their ecosystems, hunting, gathering, and horticulture also played significant roles. In addition to these material dimensions, Indian worldviews were also important; where humans were seen as one species among many others with which humans engage in reciprocal relationships, both materially and spiritually (Deloria 1992; Salmon 2000). The remainder of this paper will review archaeological and ethnological literature to explore the various ways Aboriginal Americans shaped and interacted with Holocene savanna ecosystems in the Upper Midwest.

Keystone of the savanna
Fire

Just as the grazing, browsing, and trampling of giant herbivores had opened up and maintained Pleistocene savannas, fire maintained the open structure of Holocene savannas. These were not the high-intensity canopy fires which rapidly consume entire forests, but rather low-intensity ground fires which cleared out understory vegetation leaving canopy trees intact. Over time, frequent burning of this latter type, promotes fire-tolerant, shade-intolerant prairie/savanna vegetation at the expense of fire-intolerant, shade-tolerant mesic forest vegetation. These fires were the disturbance that prohibited ecological succession to mesic forest climax, and promoted the vegetation we consider native to the Midwestern tallgrass prairie and oak savanna (Curtis 1959; Abrams and Nowacki 2008).

The timing, frequency and geography of fires over time constitutes what ecologists call a “fire,” or “disturbance regime.” Transitional between forest and grassland, savannas require intermediate levels of disturbance – too many fires and the trees can’t regenerate, too few and the forest takes over. In fact, evidence indicates that the Central Great Plains are a relatively recent phenomena resulting from excessive burning of former savanna (Axelrod 1985). Specific aspects of appropriate disturbance regimes for savanna maintenance are dependant on complex local topographic, vegetation, season, and climate conditions. Springtime fire may be deadly to a hillside covered in scraggly oak seedlings following a decade of drought, but critical for oak survival in competition with mesic species following a wet decade. While lightning may have been the ignition source in the arid early Holocene, humans have been the fire-starters for at least the last 5,000 years of a humid Midwestern climate where rains generally accompany lightning storms (Sauer 1975; Stewart 2002).

There are hundreds of documented reasons Aborigines fired the landscape (Pyne 1982; Williams 2001; Stewart 2002). In his exhaustive review, Williams (2001) condenses these into eleven inclusive purposes: hunting, crop management, improving growth and yields, fireproofing areas especially around settlements, insect collection, pest management, warfare and signaling, economic extortion, clearing areas for travel, felling trees, and clearing riparian areas. Obviously, there were many reasons that different Indigenous peoples utilized fire for different purposes under different environmental constraints. But like other aspects of their lives, there may have been motivations other than strictly utilitarian. Anthropologist and prominent fire scholar Henry Lewis (1989: 16) relates that “habitats that are overgrown and susceptible to conflagrations are considered to be ‘dirty’ or ‘wild places’ where people have neglected or foresaken their responsibilities to take care of them.” Regardless of the extent of their feeling of responsibility toward the land, Native peoples extensively utilized fire with significant ecological impacts.

These anthropogenic disturbance regimes shaped the evolution and development (Anderson 2002) of the Midwestern Holocene savanna ecosystem. Pyne (1982, 79) observes that “so extensive were the cumulative effects of these modifications that it may be said that the general consequence of the Indian occupation of the New World was to replace forested land with grassland or savannah.” Williams (2001: 2-3) concludes that the overall purpose of burning was to “promote a diversity of habitats…which gave the Indians greater security and stability to their lives.” Intermediate disturbances are generally known by ecologists to promote high levels of species diversity (Paine 1969; Grime 1973).

Not only did these anthropogenic fire regimes promote the diversity we now associate with pre-settlement ecosystems, but also its productivity. Firing promotes the growth of many fruits such as cherry, plum, strawberry, raspberry, blackberry, crabapple, and hazelnut attractive to humans and the animals they hunted (Brown 1991; Curtis 1959). The grasses and herbs that grow following fire are more nutritious and attractive to grazers such as deer and elk. And because these animals also consume acorns and nuts in the fall, savannas could support much higher large mammal populations than either forest or grassland. Abram and Nowaki (2008: 1124) speculate that, “the conscious use of fire by Midwest Indians to create grazing habitat and partially control large herbivores probably represents the most extensive form of prehistoric management anywhere in the USA.” While there is little doubt as to the the effects of such widespread burning, hunting, gathering, and horticultural activities also played a role in shaping savanna ecosystems.

Hunting, Gathering, and Horticulture

From Clovis to post-contact, hunting remained an important aspect of Aboriginal lifeways. Throughout the Holocene, a diversity of animal species were hunted. In their review of archaeological sites across Southwest Wisconsin, Theler and Boszhardt (2003) identify 43 mammal, 51 bird, 34 fish, 22 reptile, amphibian and crayfish, and 39 freshwater mussel species associated with Archaic, Woodland, and Oneota contexts. Nearly two hundred animal species were hunted, fished, gathered, and utilized as food and/or materials. These species reflect the diversity and productivity of Midwestern Holocene savannas. The most frequently hunted and important food and material source was the white-tailed deer.

Deer remains were the most abundant in all of the archaeological contexts reviewed by Theler and Boszhardt (2003). These animals were obviously both abundant and heavily utilized. Given increasing human population densities throughout the Holocene, and the skills of Native hunters, it may seem as though some sort of conservation measures must have been practiced in order to maintain sustained ungulate populations. The opposite, however, may have been the case. In his review of archaeological and ethnographic evidence, Kay (1994) shows evidence that hunters followed strategies opposite to those considered necessary to population conservation including the preferential killing of prime-aged and female individuals. Neumann (2002) conclude that Natives in the East and Midwest hunted as “non-prudent” predators, selecting young fawns and females in spring. This is exactly the hunting strategy which most reduces prey fecundity. These hunting strategies might help explain the extent to which Native populations shifted their settlements across the landscape.  Perhaps local over-hunting of deer followed by human abandonment allowed for local deer population recovery. This would facilitate regionally sustainable meta-populations of deer, and allow for cyclical settlement patterns. Over-hunting of local game populations coupled with declining fertility of agricultural fields over time, likely dictated village relocation schedules (Krech 1999).

Oscillating numbers of ungulates would have had varying effects on vegetation growth and structure. Deer are generalist browsers known to impact the population and community dynamics of herbaceous and woody vegetation. Deer browse woody saplings, especially those of oak species, meaning that sufficient deer densities prohibit oak regeneration (Waller and Alverson 1997). Widespread ungulate hunting may then have assisted in the continuing regenerative capacity of savanna oaks. Deer also consume the acorns and nuts of the mast-bearing savanna trees, putting them into direct competition with humans for a critical resource.

One of the most important resources for Archaic, Woodland, and even post-contact tribes, were the nuts from oak, hickory, and walnut trees. Not only were these rich in carbohydrates and fatty acids, but were plentiful in Eastern and Midwestern woodlands and savannas (McShea and Healy 2003). Behavioral strategies and processing technologies such as stone-grinding tools were developed in the Archaic to exploit this abundant, nutritious, and geographically extensive resource (Moore and Dekle 2010). In the southern Midwest, increased availability of deer and mast during the early Holocene transition from mesic forest to open savanna led to a shift from Archaic hunter-gatherer-forager to collector settlement strategies (Strafford et al. 2000).

Open-grown nut-bearing trees experiencing full sunlight are much more productive than their forested counterparts. Selective cutting to open up around hickory trees can increase nut production by as much as 500% within a decade (Munson 1986). It has been suggested that Native peoples intentionally managed nut-tree stands as early as the Archaic (Moore and Dekle 2010) by thinning undesirable vegetation and cutting individual trees maintaining groves of regularly-spaced trees (Asch 1994; Bonnicksen 2000; Delcourt and Delcourt 2004; Abrams and Nowacki 2008). These behaviors would have not only maximized nut production on the savanna, but would also impact plant and animal community dynamics.

Thinning and clearing vegetation represents a direct manipulation of plant community dynamics, favoring some individuals and species over others. Doing so in order to maintain productive groves would have changed light intensities on the ground, one of the main drivers of savanna understory vegetation dynamics (Leach and Givnish 1999). Perhaps even more ecologically consequential is the indirect impacts of increased stand productivity. Increased productivity of nut trees would not only provide increased resources for people, but for many other animals such as deer, elk, turkey, squirrels, and raccoons. Each of these were preferentially hunted, perhaps because of their direct competition for such a valuable resource, leading to what Neumann (2002) describes as a “mast competitive network” with humans regulating the network as keystone species. Savannas thus furnished valuable resources to its human inhabitants directly through nut production, and indirectly by supporting many other animals important to indigenous diets. Besides nut trees, Indigenous Americans harvested and utilized many other plant species for food, fiber, medicine, dyes, and ceremonial purposes.

Because of rapid decomposition of organic material in the humid Midwest, there is little archaeological evidence of prehistoric uses of plants in America. There have been many ethnobotanical studies, however, which demonstrate some of the plants and their uses. One of the most rich and comprehensive ethnobotanic records from the Upper Midwest can be found in the work of Huron Smith among the Ho-Chunk of Wisconsin (Kindscher and Hurlburt 1998). Smith cataloged nearly 150 plant species and their uses. While many of these were specialty plants cultivated in garden plots, many were harvested in the wild. Harvesting wild-grown plants obviously impacts their population and community dynamics. It is easy to imagine the excessive harvesting of certain desirable species leading to their local extinction. It seems as though some Natives had a very different outlook.

Pomo Indians of California insist that harvesting by humans enhances the growth of those species. One of their elders, Mabel McKay explains, “When people don’t use the plants, they get scarce. You must use them so they will come up again” (Bonnicksen 2000: 109). The Assiniboines of the Upper Midwest used methods of harvesting prairie turnips which facilitated their growth and persistence (Bonnicksen et al. 1999). It is likely that many gathering strategies evolved for different species allowing for both the efficient harvest of desirable materials and the promotion of local populations.

Horticulture is simply the process of plant cultivation. The most obvious form of horticulture is that of direct agriculture, the first evidence of which appears 5,000 years ago when floodplain gardens growing several varieties of squash first appeared in Illinois river valleys (Asch and Asch 1985). By 3,800 years ago, intentional selection had led to noticeable difference in the size of several oily and starchy seed-producing annual floodplain species archaeologists refer to as “the Eastern Agricultural Complex” (Smith and Yarnell 2009). This complex includes bottle gourd, sunflower, marsh elder, little barley, and two varieties of chenopod. This kind of floodplain agriculture would have required the burning or clearing of forest vegetation, and would have likely lead to soil erosion (Peacock 1998). These activities continued to intensify with the culmination of floodplain farming occurring with Mississippian maize-dependant societies. Extensive maize fields are thought to have caused nearly as much erosion as historic Euro-American agricultural practices (Neumann 2002). Indigenous horticultural activities included not just the cultivation of fields and garden plots, but also the transplanting and naturalizing of desirable species into appropriate environments.

Wild rice was widely utilized by Indigenous Americans in the Upper Midwest. French fur trader Nicolas Perrot noted that the Assiniboines regularly sowed wild rice which they would harvest and store in underground caches (Blair 1911). The former abundance of wild rice in Southern Wisconsin lakes (Brown 1927), outside of its normal range further North, is further evidence of intentional seeding and cultivation. Another heavily utilized aquatic plant was American lotus, which produces edible tubers and seeds. Its presence in the Upper Midwest is also thought to be due to Indian propagation, perhaps near villages (Curtis 1959; Brown 1991). In New England, Iroquois are thought to have transplanted and cultivated several food and medicinal species including groundnut and leek (Day 1952). There is also evidence that Aborigines planted trees.

Some early settlers remarked that Indians planted acorns (Neumann 2002). Dorney and Dorney (1989) describe a curious stand of white oak near a historic Indian village around present day Green Bay, Wisconsin. The area is surrounded by mixed conifer-hardwood forest with no other populations of oaks nearby. The authors conclude that Indian planting was responsible for the presence of the oaks. Day (1952) reports that Chestnut are found associated with Indian village sites in Ontario and are thought to have been planted. The Iroquois are thought to have planted Canada Plum and Kentucky Coffeetree due to their association with village sites. Not only were Indians likely planting desirable trees, but they were also likely intentionally selecting seeds from trees with particularly desirable traits (Martinez 1993). Aboriginal activities thus promoted the abundance and distribution of desirable fruit and nut-bearing trees. As Abrams and Nowacki (2008: 1134) suggest,

Native Americans profoundly impacted the distribution and importance of mast and fruit trees and tallgrass prairie as a primary food source through both active and passive means, and that they ubiquitously impacted these vegetation types at the regional and biome levels (not only at the local level).

These authors conclude that the massive oak and hickory savannas and forests of the Eastern U.S. were a result of Native American planting, cultivation, and burning.

Conclusion

The savanna ecosystems of Midwestern North America encountered by Euro-American settlers were the result of nearly 10,000 years of evolution through the Holocene with humans as keystone species. Through their burning, hunting, gathering, and horticultural activities, Indigenous Americans transformed much of North America into diverse, functional, and productive savanna ecosystems. These ecosystems were ideal for human habitation, supporting diverse and abundant plants and animals for food, fiber, fuel, medicine, and materials. They also provided myriad ecosystem services such as water purification, groundwater recharge, and carbon sequestration. The subsequent demise of these savanna ecosystems were thus just as much a result of Indian depopulation and forced removal, as any direct Euro-American actions on the land. Even the areas neglected by settlers transitioned from savanna to closed forest.

The oak savannas have since disappeared (Leech and Ross 1995). In their place are monocultured fields, mesic forests, and urban sprawl. None of these provide the diversity and ecological functionality of the former savannas. Our croplands provide food, but only at an immense cost to biodiversity and ecosystem functioning. We continue producing immense quantities of corn because of the machinery, fertilizer, and pesticides afforded by fossil fuels. We have substituted fossil fuels for functional ecosystems as the source of our food. And as these fuels and their derivatives become more scarce and expensive, our industrial agricultural and food system becomes increasingly vulnerable. When the oil runs out, functional ecosystems will be necessary for human survival (Hobbs and Harris 2001). In order to learn how to restore our degraded ecosystems to support human existence, it will be critical to understand how former ecosystems functioned.

The ecosystems of the Midwest that developed since the glaciers melted can not be understood without explicit consideration of the role humans played in their evolution. Perhaps the greatest lesson we can learn from these ecosystems and the people that inhabited them is not in their specific management practices, although there is certainly much to learn. Instead, I believe an important lesson is that we, too, are keystone species, living in and off of the ecosystems around us. Our Western worldview of humans as separate from nature along with the complexity of our modern society means that we mostly do not see the impacts of our behaviour on these ecosystems. But those impacts are real nevertheless. We are a part of and shape the ecosystems around us, whether we acknowledge it or not. By acknowledging this, we are thus empowered to envision the way we would like to see those ecosystems take form and the roles we will need to play in their development. Author and poet N. Scott Momaday (1970: 53) writes,

I am interested in the way that a man looks at a given landscape and takes possession of it in his blood and brain…We Americans need now more than ever before – and indeed more than we know – to imagine who and what we are in respect to the earth and sky. I am talking about an act of the imagination essentially, and the concept of an American land ethic.

In the Midwest, we have the climate, soils, and hydrology capable of supporting functional ecosystems with remarkable diversity and productivity. But nature alone will not supply such abundance. We have to acknowledge and take responsibility of our role as keystones and engage in the process of imagining and shaping our world.

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Comments

Lindsay Rebhan (@LSRebhan)

Great work Peter! I enjoy thinking about the megafauna that existed, wow and the Clovis shared weapon/tool box would be amazing to get a visual on! Long ago, my undergrad Environmental Studies capstone paper was on similar topic, with a focus on the bison role as a keystone species of the prairie ecosystem and the semi-nomadic human ecosystem managers. Tools of fire, nut cultivation, animal management and grassland soil building are vital for restoration agriculture. Thank you for the N. Scott Momaday quote – I, too, feel we must come around to an American Land Ethic. ~lindsay

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