Natural World Reflections Prose


Is our epitaph to be the fiddler playing a jig when a waltz was called for. 


Elusive Potential

by L.G.Cullens 2016

Humans being a variation of adaptive forms in the evolving dance of life it's understandable, as with any form having a measure of self-awareness, that we tend to a subjective perception of Nature. A more objective perspective though, considering the ecosphere and biodiversity that sustains our existence, shows more respect and caring for ourselves and our progeny than anything else we might do.

Considering the dance of life in natural sciences terms, the whole of potential ecosphere niches in time, space, and kind is beyond our perception. Thus natural scientists focus on what we can readily discern as measures of ecosystem stability and productivity, with emphasis on species that play critical roles. Common critical role categorizations are foundational, umbrella, indicator, and keystone, allowing for species to overlap roles.

Foundation species are those that play major roles in creating and/or maintaining a habitat that supports other species. One example is tree species that define and structure certain forest ecosystems. Another example is corals that produce reef structures on which countless other organisms live.

Umbrella species are organisms on which many other species depend. Similar to the keystone species classification, a distinguishing example is the northern spotted owl of old growth forests, that by virtue of their habitat being protected also protects mollusks and salamanders within the protective boundaries. An overlapping example is the Siberian tiger in the Russian Far East which is considered both a keystone and a umbrella species. This due to its impact as a top predator, and conservation efforts protecting their habitat also protecting myriad other species therein. 

Indicator species are any biological species that define a trait or characteristic of an environment. That is for example, their presence may delineate an ecosystem; their population may indicate ecological balance in an ecosystem; and/or a species might be early warning indicators of an environmental condition such as pollution. Species examples are stoneflies which indicate high oxygen water; some lichens which indicate levels of air pollution; fungi as a conservation measure in forests; and mollusks as a measure of water pollution.

Keystone species are species that have a disproportionately large effect on their environment relative to their abundance, in that they play a critical role in maintaining the structure of an ecological community. Disappearance of keystone species would initiate a domino (cascading) effect throughout an ecosystem, with other species increasing or disappearing and habitat being considerably altered. All species are important to ecosystem productivity (which increases with biodiversity in filling more niches), but keystone species are particularly important in maintaining stability.

Understanding that over ninety-nine percent of all species that have ever existed on Earth are now extinct, keep in mind that such has occurred in geological time with changing environmental conditions. Humans have only existed in the blink of an eye relative to geological time, and we can expect to be a liminal thread in the ever evolving gossamer web of life. Even so, relative to our own perception of time, we can have an affect on the longevity of our species. There are species, without the objective reasoning potential of humans, that have existed many millions of years. For example the sandhill crane has existed for ten million years, and the tailed frog for one hundred and fifty million years.

Until our planet becomes sterile, physical life will continue with evolution its adaptive change agent. Thus the focus here, with the longevity of humankind dependent on conducive ecosystems, is not to accelerate change, but rather to pay more attention to how other species we evolved with are faring. Believing we can alter Nature to our benefit alone rather than respectively coexist is a fallacy that accelerates unexpected and detrimental change.

Following is a sampling of critical species to increase familiarity, and maybe help to foster more awareness of our natural world underpinnings.

Beavers: These herbivorous rodents as we know them today have changed very little in North America over the last seven million years as evidenced by fossil finds. There have been other beaver species such as Castoroides, extant until about ten thousand years ago, which weighed two to three hundred pounds. Beavers are the epitome of both a foundation and a keystone species. As much as thirty to fifty percent of all post-glacial sedimentation (above bedrock) was formed from beavers’ labor. That is, the fertile landscapes we value for crops. Ongoing, they decrease damaging floods, recharge drinking water aquifers reducing droughts, help remove pollutants from surface and ground water, and decrease erosion. In doing all this they promote biodiversity for the benefit of all life forms. In North America the beaver population has been reduced by some ninety percent with the fur trade, and they are still threatened by habitat destruction, pest control, and the excesses of chemicals we use in agriculture.

Sea stars: These marine invertebrates have a lineage stretching back around four hundred and fifty million years. The term "keystone species" was developed by Dr. Robert Paine, who studied sea stars. His experimental removals of this top predator from a stretch of shoreline resulted in lower species diversity and the eventual domination of Mytilus mussels. Sea stars diverse diets and ability to adapt to different environments makes them a keystone species in their habitats. Introduced into new habitats, they have also become invasive pests. Major threats are marine pollution and rising temperatures.

Bees: These highly eusocial nectar and pollen feeding insects date back eighty plus million years in the fossil records. Pollination was well established before the first appearance of bees, but bee and plant specialization coevolution accelerated adaptive radiation of angiosperms to further diversify primary production, and in turn increase overall biodiversity for greater ecosystem productivity. Such facilitated our existence, and is responsible for a large share of the food we consume. Their continued existence is severely threatened by our agrochemical excesses. Thus they are both a keystone and indicator species.

Prairie dogs: These herbivorous rodents are a member of the ground squirrel family existing some ten to thirty million years, though it's unknown how long specific species have existed on the North American Great Plains.  Prairie dogs contribute by enhancing the soil and water quality in ecosystems; helping with water retention; promoting the diversity of vegetation, vertebrates, and invertebrates through their foraging and burrowing activities; and by their presence as prey items. Agriculture; livestock management; human infrastructure; pest control; and sport killing have reduced habitat to 2% of their former range.

Hummingbirds: These New World birds co-evolved with ornithophilous flowers. The narrow color spectrum of the flowers they feed on may render hummingbird-pollinated flowers relatively inconspicuous to most insects, which is an example of Nature's specialization. Hummingbird reduction has led to invasive plants taking over, such as buffelgrass crowding out native cactus in the Sonoran Desert. Among the most serious threats to hummingbirds, as with all birds, are agrochemicals.

Sea otters: These marine mammals of the weasel family, existing approximately five million years and becoming isolated in the North Pacific approximately two million years ago, feed on sea urchins in good part, controlling their population. If the otters didn't eat the urchins, the urchins would devour a habitat's kelp. Kelp, or giant seaweed, is a major source of food and shelter for ocean ecosystems, and without sea otters entire ocean ecosystems would collapse. Sea otter population levels were decimated by the fur trade, but have since rallied sporadically, though they are still threatened in part by pollution.

Elephants: The major species we know today have existed over a million years, with specific lineages varying in development. They maintain suitable habitats for many other species in savanna and forest ecosystems. Also important seed dispersers, many plant species have evolved seeds that are dependent on passing through an elephant’s digestive tract before they can germinate. By the mid-1980s their populations had been devastated, and poaching for meat and ivory remains a threat, along with habitat destruction and fragmentation.

Mountain lions: These predators have a lineage going back around eleven million years. Near the top of their food chain, they help control populations of deer, rabbits, raccoons, mice, and the like, and in Florida feral hogs and armadillos. In the southern part of South America, the puma is a top level predator that has controlled the population of guanaco and other species since prehistoric times. Conservation threats to the species include persecution as a pest animal, environmental degradation, and habitat fragmentation.

Acorn banksia: This is an Australian tree species in the Banksia genus, for which there are fossil records stretching back nearly sixty million years. In the Avon Wheatbelt region of Western Australia, there is a period of each year when acorn banksia is the sole source of nectar for honeyeaters, which in turn play an important pollination role for many other plant species. [Honeyeaters are a large and diverse family of small to medium-sized birds most common in Australia and New Guinea.] The loss of this one tree species could cause the honeyeater population to collapse in Western Australia, and in turn many other pollinated plants. Threats are harvesting by the cut flower industry; land clearing for urban and agricultural purposes; and climate change.

Not surprisingly the list goes on and on with such as snow geese; grizzly bears; Pacific salmon; red mangroves; sharks; sugar maples; gray wolves; bats; oaks; weevils; and parrotfish. With the total extant species estimated at over five million, we're not even aware of all the more critical relationships. Nor are we aware how many new species emerge daily as others go extinct.

Is our epitaph to be the fiddler playing a jig when a waltz was called for.

 

Life moved, as inconstant and fickle as Wind Baby, frolicking, sleeping, weeping, but never truly still. Never solid or finished. Always like water flowing from one place to the next. Seed and fruit. Rain and drought, everything traveled in a gigantic circle, an eternal process of becoming something new. But we rarely saw it. Humans tended to see only frozen moments, not the flow of things.” ― Kathleen O'Neal Gear, Bone Walker

"A human being is part of a whole, called by us the Universe, a part limited in time and space. He experiences himself, his thoughts and feelings, as something separated from the rest - a kind of optical delusion of his consciousness. This delusion is a kind of prison for us, restricting us to our personal desires and ...to affection for a few persons nearest us. Our task must be to free ourselves from this prison by widening our circles of compassion to embrace all living creatures and the whole of nature in its beauty." ― Albert Einstein