One of the most pervasive ideas that emerged from the
Darwinian revolution and that still continues to influence the consciousness of
man, is the belief that nature is fundamentally a struggle for existence, a survival
of the fittest. Most of us accept this explanation of the workings of the natural
world without ever considering its origins, its influence in shaping our
worldview, or its evidential support.
We are taught from our earliest youth that nature is competitive.
And we conjure up the image of the lion in pursuit of its prey as evidence to
support our belief. But where did this concept of the survival of the fittest
come from anyway? And should we hold that nature is fundamentally competitive?
Before the 19th century most biologists and naturalists
believed that the natural world with all of its diversity of living organisms
exemplified harmony and cooperation, not competition. So what caused this
paradigm shift? Many individuals were involved, but perhaps one of the most
important was an English clergyman by the name of Thomas Robert Malthus.
Malthus wrote an essay in 1798 entitled “An Essay on the Principle of Population”
which in retrospect, turned out to be highly influential and yet quite
controversial. The essence of his worldview was misery—poverty, scarcity,
starvation, disease and premature death. His model for understanding the
natural world was based on the following notion—since human populations grow
unchecked at a geometric rate of increase (1, 2, 4, 8, 16…) and food supplies grow
only at an arithmetic rate of increase (1, 2, 3, 4, 5…), the inevitable
outcome, as the population outstripped the food supply, would be constant struggle
leading to starvation, disease and death. Whether or not these assumptions
operate in any consistent manner within human societies is a complex question
on its own and in need of deeper investigation; however, and this is the main
point, Malthus incorrectly assumed that the same dynamic happens in the natural
world, i.e. in the animal and plant kingdoms.
Charles Darwin considered Malthus’ essay one of the most
important works he had ever read, and it became a cornerstone for his theory of
natural selection, the basis for his belief in biological evolution. Darwin
proposed that since organisms tend to reproduce at maximal rates at all times
(or so he assumed), there would eventually be an unrelenting struggle for
existence among organisms for a limited food supply. The strong, or fit, would
win this struggle or competition for existence, and the weak, or unfit, would
perish. In time, this idea of “survival of the fittest” became the standard lens
through which most of us view the natural world.
Examples of competition, we are told, are readily apparent
in practically every ecological interaction. But is this really true? Is the
default interaction between living organisms characterized by competition?
When we take the time to objectively observe the natural
world without preconceived biases, we discovered something fantastic. We
discover that the most common form of interaction in the natural world is a mutualism,
a relationship in which the interacting organisms or groups of organisms benefit.
Definitive cases of competition (whether intra-species or inter-species) are
rarely if at all observed in the wild. In fact, most classic textbook cases of
competition have completely unraveled since they were first published and
disseminated. As biologists took a closer look at these cases and gathered more
accurate data, many subtle mechanisms were uncovered, originally undetected,
operating in such a way as to avoid competition. Common strategies for avoiding
competition include geographical isolation, food specialization, time division
of a habitat, migration, dispersal mechanisms, territoriality, etc. In other
words, competition is avoided or eliminated by dividing habitats into what we
now call niches with each species having its own unique niche, a kind of “profession”
unique to each species. Even the predator/prey relationship is best understood
not as a competition but rather as a kind of balanced coexistence or dynamic
equilibrium. In a wild population undisturbed by man, predators do not
exterminate prey species. The predator species depends on the prey species as
food while the prey species depends on the predator species to keep the living
population virile and disease free.
Further, contrary to what many assumed for so long and
contrary to one of the most important maxims of Malthus’ worldview, all living
organisms are not trying to reproduce at maximal rates at all times. What ecologists
have learned over the years from a careful study of the matter is that intrinsic
biological control mechanisms exist to keep natural populations from
outstripping their food and habitat resources. We will mention two examples by
way of illustration. The first is a case brought up by Darwin himself. Of
course, his main premise is that all organisms, including elephants, are
striving to the utmost to increase their numbers. He writes, “The elephant is
reckoned the slowest breeder of all known animals…it will be safest to assume
that it begins breeding when 30 years old, and goes on breeding till 90 years
old, bringing forth 6 young in the interval, and surviving till 100 years old…after
a period of from 740 to 750 years there would be nearly 19 million elephants
alive, descended from the first pair.” So why don’t we see the world teeming
with elephants? According to Darwin, it is because they are subject to constant
suffering and enormous destruction throughout their lives. However, when the
biology was eventually studied in the wild (and not just theorized in someone’s
head), ecologists arrived at a completely different conclusion. First, the age
of reproductive maturity is quite plastic and is frequently deferred when
conditions are not favorable. Second, female elephants do not continue bringing
forth young to the age of 90, but stop somewhere around age 55. In other words,
natural elephant populations are largely self-controlled by internal biological
mechanisms. This phenomenon of reproductive maturity plasticity is very common
and has been verified in many mammals.
Another fascinating case is how a plant imposes birth
control on the herbivore that consumes it. Specifically, sagebrush controls the
reproduction rate of the California quail that eat it. After a drought, the
sagebrush develops high concentrations of plant estrogens that mimic
reproductive hormones in the quail. These estrogens inhibit ovulation in the
quail causing a sharp drop in the size of the quail population. Later, when the
rains return, the concentration of these estrogens in the sagebrush drops
precipitously and the quail population returns to normal as their reproduction
rate bounces back. Truly fascinating, is it not?
Many examples like these exist in the natural world. The
bottom line is that most species are not trying to reproduce at maximal rates
all the time. Rather, they have built in mechanisms to monitor or sense the
state of their environment in order to make adjustments to their reproductive
rates. The result is that competition resulting from a population outstripping
its food supply is effectively avoided.
Much more could be written about this topic, but this is
sufficient for an introduction to the topic. Most of the evidence for how our
ecological systems actually work was not known in the 1700s and 1800s. Without
needing to explore other potential driving forces such as personal motivation
for desiring a particular outcome from the outset, we can understand how
Malthus, Darwin and others easily accepted erroneous ideas. But there is no
excuse for us today. The data is available and open for all to investigate. We
need to reevaluate nature in a new light. The way of the natural world is not survival
of the fittest, dog eat dog, law of the jungle or as Alfred Lord Tennyson put
it, “Nature, red in tooth and claw…” These descriptions are figments of man’s
imagination. They are not accurate descriptions of the natural world. The
natural world avoids competition as much as possible because it is inefficient,
and it shuns fighting because it wastes energy. Many ecologists have been writing
about this for years, but it’s been more convenient just to ignore them.
Generally speaking, we see in nature what we want to see.
But the truth is that nature is not inherently competitive. It is quite
cooperative and harmonious. If we are to be intellectually and emotionally
honest with ourselves, as individuals, societies and nations, we can no longer
honestly justify brutality and savagery by holding up nature as our example. If
we continue to hold up nature as our teacher, we will have to change
drastically our conduct and our behavior.
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