Balance of nature
Encyclopedia
The balance of nature is a theory that says that ecological systems are usually in a stable equilibrium (homeostasis
), which is to say that a small change in some particular parameter (the size of a particular population, for example) will be corrected by some negative feedback
that will bring the parameter back to its original "point of balance" with the rest of the system. It may apply where populations depend on each other, for example in predator/prey systems, or relationships between herbivores and their food source. It is also sometimes applied to the relationship between the Earth's ecosystem, the composition of the atmosphere, and the world's weather.
The Gaia hypothesis
is a balance of nature-based theory that suggests that the Earth and its ecology may act as co-ordinated systems in order to maintain the balance of nature.
The theory that nature is permanently in balance has been largely discredited, as it has been found that chaotic changes in population levels are common, but nevertheless the idea continues to be popular.
During the later half of the twentieth century the theory was superseded by Catastrophe theory
and Chaos theory
, and in the twenty-first century by the Tipping point
. Basically, all variations on the concept are that systems remain in approximate equilibrium most of the time. Small perturbations cause negative feed back that result in fluctuations from some mean state. Some perturbations may be large enough to destabilize the system too far for a return to the previous approximate equilibrium, then a new approximate equilibrium will be established.
popular among some conservationist
s that nature was best left to its own devices, and that human
intervention into it was by definition unacceptable.
behavior within limits, where the sizes of populations change in a way that may appear random, but is in fact obeying deterministic
laws based only on the relationship between a population and its food source illustrated by the Lotka–Volterra equation. An experimental example of this was shown in an eight year study on small Baltic Sea
creatures such as plankton
, which were isolated from the rest of the ocean. Each member of the food web
was shown to take turns multiplying and declining, even though the scientists kept the outside conditions constant. An article in Journal Nature stated; "Advanced mathematical techniques proved the indisputable presence of chaos in this food web ... short-term prediction is possible, but long-term prediction is not."
eric opriasa 09
plain of Africa is thought by some ecologists to be partly due to human-set fires that created savanna
habitats.
and ecologist Kim Cuddington of Ohio University
demonstrated that at least in Midwestern America, the "balance of nature" idea is widely held among both science majors and the general student population. Like Social Darwinism the theory has been widely applied as a justification of uncontrolled capitalism, a defence of the status quo, and an argument against interventionist governments. The theory argues against organised human interventions - organised action against corruption or oppression in a society is precluded as it would disturb the current balanced equilibrium.
Homeostasis
Homeostasis is the property of a system that regulates its internal environment and tends to maintain a stable, constant condition of properties like temperature or pH...
), which is to say that a small change in some particular parameter (the size of a particular population, for example) will be corrected by some negative feedback
Negative feedback
Negative feedback occurs when the output of a system acts to oppose changes to the input of the system, with the result that the changes are attenuated. If the overall feedback of the system is negative, then the system will tend to be stable.- Overview :...
that will bring the parameter back to its original "point of balance" with the rest of the system. It may apply where populations depend on each other, for example in predator/prey systems, or relationships between herbivores and their food source. It is also sometimes applied to the relationship between the Earth's ecosystem, the composition of the atmosphere, and the world's weather.
The Gaia hypothesis
Gaia hypothesis
The Gaia hypothesis, also known as Gaia theory or Gaia principle, proposes that all organisms and their inorganic surroundings on Earth are closely integrated to form a single and self-regulating complex system, maintaining the conditions for life on the planet.The scientific investigation of the...
is a balance of nature-based theory that suggests that the Earth and its ecology may act as co-ordinated systems in order to maintain the balance of nature.
The theory that nature is permanently in balance has been largely discredited, as it has been found that chaotic changes in population levels are common, but nevertheless the idea continues to be popular.
During the later half of the twentieth century the theory was superseded by Catastrophe theory
Catastrophe theory
In mathematics, catastrophe theory is a branch of bifurcation theory in the study of dynamical systems; it is also a particular special case of more general singularity theory in geometry....
and Chaos theory
Chaos theory
Chaos theory is a field of study in mathematics, with applications in several disciplines including physics, economics, biology, and philosophy. Chaos theory studies the behavior of dynamical systems that are highly sensitive to initial conditions, an effect which is popularly referred to as the...
, and in the twenty-first century by the Tipping point
Tipping point
In sociology, a tipping point is the event of a previously rare phenomenon becoming rapidly and dramatically more common. The phrase was coined in its sociological use by Morton Grodzins, by analogy with the fact in physics that adding a small amount of weight to a balanced object can cause it to...
. Basically, all variations on the concept are that systems remain in approximate equilibrium most of the time. Small perturbations cause negative feed back that result in fluctuations from some mean state. Some perturbations may be large enough to destabilize the system too far for a return to the previous approximate equilibrium, then a new approximate equilibrium will be established.
History of the theory
The concept is very old; Nathaniel Esguerra described the relationship between predator and prey species, and commented on how they were in an essentially static balance, with predators never excessively consuming their prey populations. The "balance of nature" concept once ruled ecological research, as well as once governing the management of natural resources. This led to a doctrineDoctrine
Doctrine is a codification of beliefs or a body of teachings or instructions, taught principles or positions, as the body of teachings in a branch of knowledge or belief system...
popular among some conservationist
Conservationist
Conservationists are proponents or advocates of conservation. They advocate for the protection of all the species in an ecosystem with a strong focus on the natural environment...
s that nature was best left to its own devices, and that human
Human
Humans are the only living species in the Homo genus...
intervention into it was by definition unacceptable.
Predator prey interactions
Predator-prey populations tend to show chaoticChaos theory
Chaos theory is a field of study in mathematics, with applications in several disciplines including physics, economics, biology, and philosophy. Chaos theory studies the behavior of dynamical systems that are highly sensitive to initial conditions, an effect which is popularly referred to as the...
behavior within limits, where the sizes of populations change in a way that may appear random, but is in fact obeying deterministic
Determinism
Determinism is the general philosophical thesis that states that for everything that happens there are conditions such that, given them, nothing else could happen. There are many versions of this thesis. Each of them rests upon various alleged connections, and interdependencies of things and...
laws based only on the relationship between a population and its food source illustrated by the Lotka–Volterra equation. An experimental example of this was shown in an eight year study on small Baltic Sea
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
creatures such as plankton
Plankton
Plankton are any drifting organisms that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. That is, plankton are defined by their ecological niche rather than phylogenetic or taxonomic classification...
, which were isolated from the rest of the ocean. Each member of the food web
Food web
A food web depicts feeding connections in an ecological community. Ecologists can broadly lump all life forms into one of two categories called trophic levels: 1) the autotrophs, and 2) the heterotrophs...
was shown to take turns multiplying and declining, even though the scientists kept the outside conditions constant. An article in Journal Nature stated; "Advanced mathematical techniques proved the indisputable presence of chaos in this food web ... short-term prediction is possible, but long-term prediction is not."
eric opriasa 09
Human intervention
Although some conservationist organizations argue that human activity is incompatible with a balanced ecosystem, there are numerous examples in history showing that several modern day habitats originate from human activity: some of Latin America's rain forests owe their existence to humans planting and transplanting them, while the abundance of grazing animals in the SerengetiSerengeti
The Serengeti ecosystem is a geographical region in Africa. It is located in north Tanzania and extends to south-western Kenya between latitudes 1 and 3 S and longitudes 34 and 36 E. It spans some ....
plain of Africa is thought by some ecologists to be partly due to human-set fires that created savanna
Savanna
A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
habitats.
Continued popularity of the theory
Despite being discredited among ecologists, the theory is widely held to be true in the wider population: a report written by psychologist Corinne Zimmerman of Illinois State UniversityIllinois State University
Illinois State University , founded in 1857, is the oldest public university in Illinois; it is located in the town of Normal. ISU is considered a "national university" that grants a variety of doctoral degrees and strongly emphasizes research; it is also recognized as one of the top ten largest...
and ecologist Kim Cuddington of Ohio University
Ohio University
Ohio University is a public university located in the Midwestern United States in Athens, Ohio, situated on an campus...
demonstrated that at least in Midwestern America, the "balance of nature" idea is widely held among both science majors and the general student population. Like Social Darwinism the theory has been widely applied as a justification of uncontrolled capitalism, a defence of the status quo, and an argument against interventionist governments. The theory argues against organised human interventions - organised action against corruption or oppression in a society is precluded as it would disturb the current balanced equilibrium.