The phrase most often used to defend the notion that Darwin suggested that man may act with impunity towards other creatures is “survival of the fittest.” This concept, which is often inaccurately attributed to Darwin, was in fact first coined by the British polymath Herbert Spencer in his 1864 book, Principles of Biology. Spencer used the term as a way to compare his theories on economics with Darwin’s idea of “natural selection.” Spencer’s own definition for survival of the fittest was as “the preservation of favoured races in the struggle for life.” (Principles of Biology,1864, vol. 1, p. 444)
Although he later adopted survival of the fittest as a synoym for natural selection in the fifth edition of his seminal book, Darwin described the principle in a more nuanced, layered manner:
“Owing to this struggle for life, any variation, however slight and from whatever cause proceeding, if it be in any degree profitable to an individual of any species, in its infinitely complex relations to other organic beings and to external nature, will tend to the preservation of that individual, and will generally be inherited by its offspring.” (On the origin of species...London: John Murray. 1859 [1st edition] p. 61)
Darwin prefaced his discussion on the struggle for existence by explaining that he used the term “in a large and metaphorical sense, including dependence of one being on another, and including (which is more important) not only the life of the individual, but success in leaving progeny.” (p. 62) He followed this with a number of examples to illustrate how checks on population work, and often pointed out that a given species’ level of success was usually entirely dependent on another species:
“I have, also, reason to believe that humble-bees are indispensable to the fertilisation of the heartsease (Viola tricolor), for other bees do not visit this flower. From experiments which I have tried, I have found that the visits of bees, if not indispensable, are at least highly beneficial to the fertilisation of our clovers; but humble-bees alone visit the common red clover (Trifolium pratense), as other bees cannot reach the nectar. Hence I have very little doubt, that if the whole genus of humble-bees became extinct or very rare in England, the heartsease and red clover would become very rare, or wholly disappear.” (p. 73-74)
By drawing connections between whole chains of species and noting the complex relational webs between them, Darwin contributed to our early understanding of what we today call ecosystems. Indeed, without having a word for the ecological niche, he nevertheless set forth a surprisingly sophisticated depiction of it, even highlighting it as the flashpoint of competition:
“As species of the same genus have usually…some similarity in habits and constitution, and always in structure, the struggle will generally be more severe between species of the same genus…than between species of distinct genera.” (p. 76)
As if all of these caveats to the misappropriated notion of unfettered competition between all species weren’t enough, Darwin explicitly said at the end of the third chapter of his book that, in the course of trying to suss out the most advantageous adaptations for success, it would be nearly impossible to take into full account all of the interrelationships involved. “It will convince us of our ignorance,” he noted, “on the mutual relations of all organic beings; a conviction as necessary, as it seems to be difficult to acquire.” (p. 72)
The common misapprehension that leads to arguments that place Darwin at the head of an anthropomorphic, narcissistic worldview is one that contorts the observations of science into moral decrees. Although science can and should be used to inform our conceptions of the world, it is a mistake to assume that scientific theories are meant to determine moral values. By definition, science is provisional; inferring anything greater than the relatively narrow principles discovered by it does a disservice to its cause, and poses a danger for the ideologue, who is less apt or able to refine and revise his grandiloquent philosophies once they are erected.
This becomes apparent when we begin to consider how evolution and concomitant theories have changed over the years. Darwin, of course, did not foresee all of the implications of his own work. He was not a conservationist; during his famous journey to the Galapagos Islands, he collected many specimens of rare flora and fauna. He was firmly rooted in 19th century natural philosophy, conducting dissections and experiments on creatures without the slightest fear that he would disrupt the ecological balance.
Nevertheless, the germs of conservation were inherent in his theories, and laid the groundwork for further investigations that would eventually lead to environmentalism and biological conservationism (not to mention the fields of evolutionary biology, genetics, aspects of modern germ theory, and a host of other scientific pursuits). As relevant as they remain, to end one’s reasoning at Darwin is to ignore the 150 years of new insights that his ideas have engendered.
One example of the way in which evolutionary theory has led to unforeseen paradigms involves the hypothesis that we may today be in the midst of a major extinction. A greater understanding of the ways in which species interact and depend on one another, even when those interactions are removed by degrees, has led to a growing concern among scientists and many laypersons about the current state of our biosphere.
Broad censuses of plant and animal populations were first begun during the time of Carolus Linnaeus a century before Darwin, and survive today as a routine staple of scientific fieldwork. Although originally geared toward discovery and classification, observations in this field, coupled with evolutionary theory and the budding science of paleontology, began to turn toward answering questions about behavior and population demographics. When a researcher would return to a remote spot armed with the notes of a predecessor and realize that the creatures in that area were more numerous, or gone, or had adapted to some change in the landscape, he would begin to wonder how those specific changes had occurred, and what the extent of the changes were. In other words, the general theory of evolution began to find more robust and exacting applications.
Over many years, population data accumulated to the point where it was possible to look at larger trends among varied communities. Meanwhile, paleontology (another field highly dependent on evolutionary theory) had grown increasingly sophisticated, and was offering a fairly comprehensive history of life’s development on Earth. This history included several cataclysmic periods of extinction, as well as a “background rate” of species disappearance during normal times.
Once current population data and pre-historical data were compared, it became apparent that the current rate of extinctions was well above the average rate. In a 2006 article on the subject, John Baez, a mathematical physicist at the University of California Riverside, compared some of the estimates that have been postulated:
“Phillip and Donald Levin estimate that right now one species is going extinct every 20 minutes, and that half of bird and mammal species will be gone in 200 to 300 years. Richard Leakey estimates a loss of between 50,000 and 100,000 species a year, and says that only during the Big Five mass extinctions was the rate comparably high. E. O. Wilson gives a similar estimate. In his book, Michael Benton reviews the sources of uncertainty and makes an estimate of his own: given that there are probably somewhere between 20 and 100 million species in total, he estimates an extinction rate of between 5,000 and 25,000 species per year. This means between 14 and 70 species wiped out per day.” (Extinction. http://math.ucr.edu/home/baez/extinction/)
Baez is careful to point out that these estimates are based on extrapolations of known populations – that there are many species for which no reliable data yet exists. The consensus, even among the most conservative skeptics that he quotes, however, shows that the rate is well above anything considered normal.
Image courtesy of math.ucr.edu
The concern over mass extinction would have been impossible for Darwin – he simply did not have the information available to him. Were he alive today, though, there is little doubt that he would have shared this concern, for it originates almost entirely from principles he fathered. It would be imprudent and irresponsible to suppose that because he never mentioned the possibility that we were witnessing a period of major extinctions that he would condone ignoring such information were it presented to him. By the same token, those of us alive today cannot base our conclusions about existence solely on the basis of a few century-old texts.
Extinctions, as unpalatable as they are, don’t necessarily mean that we should care about what happens to other forms of life, though. One thing that paleontology has shown us is that the worst tragedies always give rise to new life, often driving evolution into heretofore untold realms. Why, then, should we concern ourselves with other creatures?
One answer comes, in fact, from the necessity of survival and natural selection. Darwin’s observations about the interrelations of ecological systems included humans as part of the pantheon. This key point, which has caused so much controversy within religious institutions, is what makes our participation in keeping the biosphere in balance so vital. We, too, are subject to the scarcity, competition and other economies of nature, and we are highly adapted to depend on other living beings.
The musings about flowers’ dependence on bees that Darwin made in On the Origin of Species is perhaps of greater relevancy today than ever before. All angiosperms rely on some mechanism outside of the plant for pollination, and for a large proportion, that mechanism is the bee. But recently, North America has been suffering from a crisis that could endanger not only insects and flowers, but humans as well.
The culprit behind this crisis is a phenomenon called Colony Collapse Disorder (CCD). According to the Mid-Atlantic Apiculture Research and Extension Consortium, a regional task force formed in 1997 to address pest management in the beekeeping industry, CCD is characterized by “sudden colony death with a lack of adult bees in/in front of the dead-outs. Honey and bee bread are usually present and there is often evidence of recent brood rearing. In some cases, the queen and a small number of survivor bees may be present in the brood nest.”(Colony Collapse Disorder. http://maarec.psu.edu/ColonyCollapseDisorder.html)
No one knows what causes CCD. Hypotheses range from pesticides to parasites to climate change, with many scientists now convinced that the answer may involve a suite of factors.
Regardless of its cause, CCD poses a very real threat to human agriculture and food supplies. To understand why this is, one need only look at the vastness of the beekeeping industry in the United States, and the contribution it makes to food production:
“Bee pollination is responsible for $15 billion in added crop value, particularly for specialty crops such as almonds and other nuts, berries, fruits, and vegetables. About one mouthful in three in the diet directly or indirectly benefits from honey bee pollination. While there are native pollinators (honey bees came from the Old World with European colonists), honey bees are more prolific and the easiest to manage for the large scale pollination that U.S. agriculture requires. In California, the almond crop alone uses 1.3 million colonies of bees, approximately one half of all honey bees in the United States, and this need is projected to grow to 1.5 million colonies by 2010.” ( Questions and Answers: Colony Collapse Disorder. http://www.ars.usda.gov/News/docs.htm?docid=15572)
If bee populations were to decline below sustainable levels, it would cause major setbacks for the growth of many crops in the U.S., which produces as much food for export to other nations as it does for its own citizens. Such a disruption in food supplies would cause havoc immediately in world economies, as food costs rose dramatically. It would also endanger food stocks that are already in peril from overpopulation and shifts in climate. Over the long term, world hunger would spike, and replenishing crops could become a much more difficult process that might never reach the level of output now enjoyed.
Humans’ relationship with bees is, of course, only one poignant example of the myriad ways in which we depend on other species for our own survival. The fact is that we depend on hundreds of other creatures for almost everything we do, from feeding us to producing silk ties to guiding the blind. When one extrapolates to include all of the interconnections between the species we use and the species we do not, almost no living thing on the planet can be excluded from the mix without that loss rippling back to affect humans.
It is this fact, no matter how one wishes to interpret the idea of evolutionary competition, that forces us to concern ourselves with the state of other species. Without them, we too would soon disappear.
It therefore makes no sense whatsoever to conclude from popular conceptions of Darwinian competition that we ought to ignore other species. Darwin never proposed it. Even if he had, it would be folly to narrow today’s understanding of evolution and ecosystem interaction to the parameters of a single man, dead long ago. Finally, the basic principles of Darwinian evolution place us in a position to realize that there are legitimate selfish reasons to pay attention to other forms of life – because we are all connected, both through our pasts and in the present.
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