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Darwinian Theory of Evolution

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Introduction

Theories explaining biological evolution have been bandied about since the ancient Greeks, but it was not until the Enlightenment of the 18th century that widespread acceptance and development of this theory emerged. In the mid 19th century English naturalist Charles Darwin – who has been called the”father of evolution” – conceived of the most comprehensive findings of organic evolution ever. Today many of his principles still entail modern interpretation of evolution.

I’ve assessed and interpreted the basis of Darwin’s theories on evolution, incorporating a number of other factors concerning evolutionary theory in the process.

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Criticism of Darwin’sconclusions abounds somewhat more than has been paid tribute to, however, Darwin’s findings marked a revolution of thought and social upheaval unprecedented in Western consciousness challenging not only the scientific community but the prominent religious institution as well. Another revolution in the science of lesser nature was also spawned by Darwin, namely the remarkable simplicity with which his major work The Origin of the Species was written – straightforward English, anyone capable of alogical argument could follow it – also unprecedented in the scientific community (compare this to Isaac Newton’s horribly complex work taking the scientific community years to interpret).

Evolutionary and revolutionary in more than one sense of each word. Every theory mentioned in the following reading in fact falls back to Darwinism.

Darwinian Theory of Biological Evolution

The modern conception of species and the idea of organic evolution had been part of Western consciousness since the mid-17th century (a la John Ray), but wide-range acceptance of this idea, beyond the bounds of the scientific community, did notarise until Darwin published his findings in 1958. Darwin first developed his theory of biological evolution in 1938, following his five-year circumglobal voyage in the southern tropics (as a naturalist) on the H.M.S. Beagle, and perusal of one ThomasMalthus’ An Essay on the Principle of Population which proposed that environmental factors, such as famine and disease limited human population growth. This had a direct bearing on Darwin’stheory of natural selection, furnishing him with an enhanced conceptualization of the “survival of the fittest” – the competition among individuals of the same species for limited resources – the “missing piece” to his puzzle. For fear of contradicting his father’s beliefs, Darwin did not publish his findings until he was virtually forced after Alfred Wallace sent him a short paper almost identical to his own extensive works on the theory of evolution. The two men presented a joint paper to the Linnaean Society in 1958 – Darwin published a much larger work (“a mere abstract of my material”) Origin of the Species a year later, a source of undue controversy and opposition (from pious Christians), but remarkable development for evolutionary theory.

Their findings basically stated that populations of organisms and individuals of a species were varied: some individuals were more capable of obtaining mates, food and other means of sustenance, consequently producing more offspring than less capable individuals. Their offspring would retain some of these characteristics, hence a disproportionate representation of successive individuals in future generations. Therefore future generations would tend to have those characteristics of more accommodating individuals. This is the basis of Darwin’s theory of natural selection: those individuals incapable of adapting to change are eliminated in future generations, “selected against”.

Darwin observed that animals tended to produce more offspring than were necessary to replace themselves, leading to the logical conclusion that eventually the earth would no longer be able to support an expanding population. As a result of the increasing population, however, war, famine and pestilence also increase proportionately, generally maintaining a comparatively stable population.

Twelve years later, Darwin published a two-volume work entitled The Descent of Man, applying his basic theory to the like comparison between the evolutionary nature of man and animals and how this relates to the socio-political development man and his perception of life. “It is through the blind and aimless progress of natural selection that man has advanced to his present level in love, memory, attention, curiosity, imitation, reason, etc. as well as progress in “knowledge morals and religion”.

Here is where originated the classic idea of the evolution of man from ape, specifically where he contended that Africa was the cradle of civilization. This work also met with opposition but because of the impact of his “revolutionary” initial work this opposition was comparatively muted.

A summary of the critical issues of Darwin’s theory might be abridged into six concise points as follows:

  1. Variation among individuals of a species does not indicate deficient copies of an ideal prototype as suggested by the platonic notion of Eidos. The reverse is true: variation is integral to the evolutionary process.
  2. The fundamental struggle in nature occurs within a single species population to obtain food, interbreed, and resist predation. The struggle between different species (ie. foxvs. hare) is less consequential.
  3. The only variations pertinent to evolution are those which are inherited.
  4. Evolution is an ongoing process that must span many moons to become detectably apparent.
  5. The complexity of a species may not necessarily increase with the evolutionary process – it may not change at all, even decrease.
  6. Predator and prey have no underlying purpose for maintenance of any type of balance – natural selection is opportunistic and irregular.

The Theory of Biological Evolution: Contributing Elements

The scientific range of biological evolution is remarkably vast and can be used to explain numerous observations within the field of biology. Generally, observation of any physical, behavioral, or chemical change (adaptation) over time owing directly to the considerable diversity of organisms can be attributed to the biological evolution of species. It might also explain the location (distribution) of species throughout the planet.

Naturalists can hypothesize that if organisms are evolving through time, then-current species will differ considerably from their extinct ancestors. The theory of biological evolution brought about the idea for a record of the progressive changes a nearly, extinct species underwent. Through the use of this fossil, record paleontologists are able to classify species according to their similarity to ancestral predecessors, and thereby determine which species might be related to one another. Determination of the age of each fossil will concurrently indicate the rate of evolution, as well as precisely which ancestors preceded one another and consequently which characteristics are retained or selected against. Generally, this holds true: probable ancestors do occur earlier in the fossil record, prokaryotes precede eukaryotes in the fossil record. There are, however, significant”missing links” throughout the fossil record resulting from species that were, perhaps, never fossilized – nevertheless, it is relatively compatible with the theory of evolution13.

It can be postulated that organisms evolving from the same ancestor will tend to have similar structural characteristics.

New species will have modified versions of preexisting structures as per their respective habitats (environmental situations).

Certainly, these varying species will demonstrate clear differentiation in important structural functions, however, an underlying similarity will be noted in all. In this case the similarity is said to be homologous, that is, structure origin is identical for all descended species but very different in appearance. This can be exemplified in the pectoral appendages of terrestrial vertebrates: Initial impression would be that disparate structure, however in all such vertebrates four distinct structural regions have been defined: the region nearest the body (humerus connecting to the pectoral girdle, the middle region (two bones, radius and ulna are present), a third region – the “hand” – of several bones (carpal and metacarpal, and region of digits or “fingers”. Current species might also exhibit similar organ functions, but are not descended from the same ancestor and therefore different in structure. Such organisms are said to be analogous and can be exemplified in tetrapods, many containing similar muscles but not necessarily originating from the same ancestor. These two anatomical likenesses cannot be explained without a considerable understanding of the theory of organic evolution.

The embryology or early development of species evolved from the same ancestor would also be expected to be congruent.

Related species all share embryonic features. This has helped in determining reasons why development takes place indirectly, structures appearing in the embryonic stage serve no purpose, and why they are absent in adults. All vertebrates develop a notochord,gill slits (greatly modified during the embryonic cycle) and tail during early embryology, subsequently passing through stages in which they resemble larval amphioxus, then larval fishes.

The notochord will only be retained as discs, while only the ear canal will remain of the gills in adults. Toothless Baleenwhales will temporarily develop teeth and hair during early embryology leading to the conclusion that their ancestors had these anatomical intricacies. A similar pattern exists in almost all animal organisms during the embryonic stage for numerous formations of common organs including the lungs and liver. Yet there is a virtually unlimited variation of anatomical properties among adult organisms. This variation can only be attributed to evolutionary theory15.

Biological evolution theory insists that in the case of a common ancestor, all species should be similar on a molecular level. Despite the tremendous diversity in structure, behavior and physiology of organisms, there is among them a considerable amount of molecular consistency. Many statements have already been made to ascertain this: All cells are comprised of the same elemental organic compounds, namely proteins, lipids and carbohydrates. All organic reactions involve the action of enzymes. Proteins are synthesized in all cells from 20 known amino acids. In all cells, carbohydrate molecules are derivatives of six-carbon sugars (and their polymers).

Glycolysis is used by all cells to obtain energy through the breakdown of compounds. Metabolism for all cells as well as the determination of definitude of proteins through intermediate compounds is governed by DNA. The structure for all vital lipids, proteins, some important co-enzymes and specialized molecules such as DNA, RNA and ATP are common to all organisms.

All organisms are anatomically constructed through the function of the genetic code. All of these biochemical similarities can be predicted by the theory of biological evolution but, of course, some molecular differentiation can occur. What might appear as minor differentiation (perhaps the occurrence-frequency of a single enzyme) might throw species into entirely different orders of mammals (ie. cite the chimpanzee and horse, the differentiation resulting from the presence of an extra 11cytochrome c respiratory enzymes). Experts have therefore theorized that all life evolves from a single organism, the changes have occurred in each lineage, derived in concert from common ancestor16.

Breeders had long known the value of protective resemblance along before Darwin or any other biological evolution theorists made their mark. Nevertheless, evolutionary theory can predict and explain the process by which offspring of two somewhat different parents of the same species will inherit the traits of both – or rather how to ensure that the offspring retains the beneficial traits by merging two of the same species with like physical characteristics. It was the work of Mendel that actually led to more educated explanations for the value in protective resemblance. The Hardy-Weinburg theory specifically, employs Mendel’s theory to a degree to predict the frequency of occurrence of dominantly or recessively expressing offspring.

Population genetics is almost sufficient in explaining the basis for protective resemblance. Here biological evolutionary theory might obtain its first application to genetic engineering18.

Finally, one could suggest that species residing in a specific area might be placed into two ancestral groups: those species with origins outside of the area and those species evolving from ancestors already present in the area. Because the evolutionary process is so slow, spanning over considerable lengths of time, it can be predicted that similar species would be found within comparatively short distances of each other, due to the difficulty for most organisms to disperse across an ocean.

These patterns of dispersion are rather complex, but it is generally maintained by biologists that closely related species occur in the same indefinite region. Species may also be isolated by geographic dispersion: they might colonize an island, and over the course of time evolve differently from their relatives on the mainland. Madagascar is one such example – in fact approximately 90 percent of the birds living there are endemic to that region. Thus as predicted, it follows that speciation is concurrent with the theory of biological evolution.

Wallace’s Contributions

There is rarely a sentence written regarding Wallace that does not contain some allusion to Darwin. Indeed, perhaps the single most significant feat he preformed was to compel Darwin to enter the public scene. Wallace, another English naturalist had done extensive work in South America and southeast Asia(particularly the Amazon and the Malay Archipelago) and, like Darwin, he had not conceived of the mechanism of evolution until he read (recalled, actually) the work of Thomas Malthus – thenotion that “in every generation, the inferior would be killed off and the superior would remain – that is the fittest would survive”. When the environment changed, therefore, he determined”that all the changes necessary for the adaptation of the species… would be brought about; and as the great changes are always slow there would be ample time for the change to be affected by the survival of the best fitted in every generation”. He saw that his theory supplanted the views of Lamarck and the Vistagesand annulled every important difficulty with these theories.

Two days later he sent Darwin (leading naturalist of the time) a four-thousand-word outline of his ideas entitled “On the Which has Regulated the Introduction”. This was more than merely cause for Darwin’s distress, for his work was so similar to Darwin’s own that in some cases it parallelled Darwin’s own phrasing, drawing on many of the same examples Darwin hit upon.

Darwin was in despair over this, years of his own work seemed to go down the tube – but he felt he must publish Wallace’s work.

Darwin was persuaded by friends to include extracts of his own findings when he submitted Wallace’s work On the Law Which has regulated the Introduction of New Species to the Linnaean Society in 1858, feeling doubly horrible because he felt this would be taking advantage of Wallace’s position. Wallace never once gave the slightest impression of resentment or disagreement, even to the point of publishing a work of his own entitled Darwinism.

This itself was his single greatest contribution to the field: encouraging Darwin to publish his extensive research on the issues they’d both developed.

He later published Contributions to the Theory of natural selection, comprising the fundamental explanation and understanding of the theory of evolution through natural selection. He also greatly developed the notion of natural barriers which served as isolation mechanisms, keeping apart not only species but also whole families of animals – he drew up aline (“Wallace’s line”) where the fauna and flora of southeast Asia were very distinct from those of Australasia.

Morphological & Biological Concepts

Species have been traditionally described based on their morphological characteristics. This has proven to be somewhat premature to say the least: some organisms in extremely different forms are quite similar in their genetic make-up. Male and females in many species develop more than a few many characteristic physical differences, yet are indeed the same species (imagine that!). Likewise, some organisms appear to be quite morphologically similar but are completely incompatible.

There are many species of budworm moths, all of which are highly indistinguishable – most of which do not interbreed.

The idea of species is usually called the biological species concept, stressing the importance of interbreeding among individuals in a population as a general description. An entire population might be thought of as a single unit of evolution.

However similar difficulties arise in attempting a universal application of this theory. Because morphologically similar species occur in widely separated regions, it is virtually impossible to exact whether they could or could not interbreed.

One might ask whether cactus finches from the Galapagosinterbreed – the answer may invariably be yes…but due rather to the morphological similarities between them. Consider further asexually producing species, which can be defined by appearance alone: each individual would have to be defined as different biological species – a fact that would remain irrelevant. There are also cases for which no real standard can be applied – the donkey and horse, for example, can mate and produce healthy offspring, mules which are almost always sterile and therefore something completely undefinable. Therefore, despite seeming ideal in its delimitation, the biological species concept can not be employed in describing many natural species. It is nonetheless a popular concept for theoretical discussions since it can distinguish which populations might evolve through time completely independent of other similar populations.

Species classification is therefore not defined by fixed principles surrounding biological and morphological classifications both. The random nature of evolution itself is predictable perhaps only in that one respect: that it remains virtually unpredictable. In accordance with the Hardy-Weinbergtheory, the proportion of irregularity should not necessarily increase, but because, by its own admission this theory cannot be employed as a standard but merely to predict results, even it is limited random un-law of nature.

Bio-Evolution: Population vs. Individuals

According to the theory of evolution, all life or most of it originated from the evolution of a single gene. All relatives – species descended from a common ancestor – by definition share a certain percentage of their genes. If naught else than these genes are of a very similar nature. A species depends on the remainder of its population in developing characteristics that allow easier adaptability to the changing environment. These modified genes will ultimately express themselves as new species or may be passed on to other populations within a given species. For these traits to be expressed individually is certainly not going to benefit the species (ie. the mule retains remarkable traits but can not reproduce – they’re also a literal pain in the ass to generate).

Nevertheless should but one individual in a million retain beneficial characteristic, the opportunity for this to be passed onis significantly increased. In short order, as per natural selection highly adapted species can develop where they were dying out (over centuries to be sure, but dying out nonetheless)only a (‘n evolutionarily) short span of time ago. Plant breeders especially know the value of the gene pool. They depend on the gene pool of the wild relatives of these plants to develop strains that are well adapted to local conditions (here we refer to comparatively exotic plants). The gene pool is there for all compatible species (and that could be a large amount down theline) to partake of – given the right random conditions and the future for plant breeders brightens45.

Mechanisms for Genetic Variation

There are a number of known factors that are capable of changing the genetic structure of a population, each inconsistent with the hardy-Weinberg principle. Three primary contributing factors migration, mutation, and selection and are referred to as systematic processes – the change in gene frequency is comparatively predictable in direction and quantity. The dispersive process of genetic is predictable only in quantitative nature. When species are sectioned into diverse, geographically isolated populations, the populations will tend to evolve differently on account of the following accepted standards:

  1. Geographically isolated populations will mutate exclusively to their population.
  2. The adaptive value for these mutations and gene combinations will differentiate per each population.
  3. Different gene frequencies existed before the population was isolated and are therefore not representative of their ancestors.
  4. During intervals of small population, size gene frequencies will be fluctuating and unpredictable forming a genetic”bottleneck” from which all successive organisms will arise.

Gene frequencies can be altered when a given population is exposed to external populations, the change in frequency modified as per the proportion of foreigners to the mainstream population.

Migration may be eliminated between two populations in regions of geographic isolation, which will isolate in turn, the gene pools within the population. If this isolation within-population develops over a sufficient span of time the physical differences between two given gene pools may render them incompatible. Thus have the respective gene pools become reproductively isolated and are now defined as biologically different species. However, speciation (division into new species) does not arise exclusively from division into new subgroups inside a population, other aspects might be equally effective.

The primary source for genetic variability is a mutation, usually the cause of depletion of species’ fitness but sometimes more beneficial. The ability of a species to survive is dependent on its store of genetic diversity, allowing the generation of new genotypes with a greater tolerance for changing the environment.

However, some of the best-adapted genotypes may still be unable to survive if environmental conditions are too severe. Unless new genetic material is obtained outside the gene pool, evolution will have a limited range of tolerance for change. Generally speaking, spontaneous mutations whether they are required or not.

This means many mutations are useless, even harmful under current environmental conditions. These crippling mutations are usually weeded out or kept at low frequencies in the population through natural selection. The mutation rate for most gene loci is between one in 100 thousand to one in a million. Therefore, although mutations are the source of genetic variability, even without natural selection changes in the population would be unnoticeable and very slow. Eventually, if the only pressure affecting the locus is from mutation, gene frequencies will change and fall back to comparative equilibrium.

The fundamental restriction on the validity of the Hardy-Weinberg equilibrium law occurs where population size immeasurably large. Thus the disseminating process of genetic drift is applicable for gene frequency alteration in situations of small populations. In such a situation inbreeding is unavoidable, hence the primary contributing factor for change of gene frequencies through inbreeding (by natural causes) is genetic drift. The larger the sample size, the smaller the deviation will be from predicted values. The action of sampling gametes from a small gene pool has a direct bearing on genetic drift. Evidence is observed via the random fluctuation of gene frequencies per each successive generation in small populations systematic processes are not observed as contributing factors.

From these four basic assumptions have been made for idealized populations as follows:

  1. Mating and self-fertilization in respective subgroups of given populations are completely random.
  2. Overlap of one generation to its successor does not occurallotting distinct characteristics for each new generation.
  3. In all generations and lines of descent, the number of possible breeding individuals is the same.
  4. Systematic factors such as migration, mutation and natural selection are defunct.

In small populations, certain alleles, perhaps held as common to a species may not be present. The alleles will have become randomly lost somewhere in the population in the process of genetic drift. The result is much less variability among small populations among larger populations. If every locus is fixed in these small populations they will have no genetic variability, and therefore be unable to generate new adaptive offspring through genetic recombination. The ultimate fate of such a population, if it remains isolated, is extinction.

Genetic Variation: Speciation

Through genetic variation, new species will arise, in a process termed speciation. It is generally held that speciation occurs as two given species evolve their differences over large spans of time – these differences are defined as their genetic variation. The most popular model used to explain how species formed is the geographic speciation model, which suggests that speciation occurs only when an initial population is divided into two or smaller populations – via genetic variation through systematic means of mutation, natural selection or genetic drift- geographically isolated (physically separated) from one another. Because they are isolated, gene flow (migration) can not occur between the respective new populations51. These “daughter” populations will eventually adapt to their new environment through genetic variation (the process of evolution). If the environments of each isolated population are different then they would be expected to adapt to different conditions and therefore evolve differently. According to the model of geographic speciation, the daughter populations will eventually evolve sufficiently to become incompatible with one another (therefore unable to interbreed or produce viable offspring). As a resultof this incompatibility, gene flow could not effectively occur even if the populations were no longer geographically isolated.

The differentiated, but closely related species are now termed species pair, or species group. Eventually, differentiation will progress far enough for them to be defined as different species.

While divergence is a continuing process, it does not necessarily occur at a constant rate – fluctuating between extremely rapid rates and very slow rates of evolution. Two standard methods have been postulated for the occurrence of geographic speciation:

  • i) Individuals from a species might populate a new, isolated region of a given area (such as an island). Their offspring would evolve geographically isolated from the original species. Eventually, geographical isolation from the population on the mainland would evolved distinguishable characteristics.
  • ii) Individuals might alternately be geographically isolated as physical barriers arise or the range of the species or individuals of a population diminishes.

However, neither of these forms of speciation through geographic isolation and consequent individual genetic variation have been observed or studied directly because of the time span and general difficulty of unearthing desired fossils. Evidence for this form of speciation is therefore indirect and based on postulated theory.

Speciation vs. Convergent Evolution

Speciation is substantially more relevant to the evolution of species than convergent evolution. Through natural selection, similar characteristics and ways of life may be evolved by diverse species inhabiting the same region, in what is called convergent evolution – reflecting the similar selective pressure of similar environments. While separate populations of the same species occupying similar habitats may also evidence similar physical characteristics – due primarily to the environment rather than their species origin – it should be noted that they progressed from the same ancestor. A defining principle for the alternate natures of speciation and convergent evolution put simply: speciation results from a common ancestor, convergent evolution results from any number of ancestors58.

Morphologically similar populations resulting from the same ancestor may be compatible and able to produce viable offspring(if in some occasions not fertile offspring). Morphologically similar species resulting from different ancestors are never compatible with one another – even if they are virtual morphological twins. In fact, morphologically disparate populations of the same species may be compatible with one another – whereas those disparate through convergent evolution would be more than merely incompatible, they may be predator and prey. Convergent evolution may only account for single specific physical characteristics of very disparate, unrelated species -such as the development of flipper-like appendages for the sea turtle (reptile), penguin (bird) and walrus (mammal)59.

Concept of Adaptation

If individuals were unable to adapt to changes in the environment they would be extinct in short order. Adaptability is often based on nuclear inheritance down the generations.

Should an organism develop a resistance to certain environmental conditions, this characteristic may be passed down through the gene pool, and then through natural selection be dominant for all organisms of a given population.

Bacteria are able to accomplish this feat at a remarkably fast rate. Most, if not all forms of bacteria are compatible with one another, which is able to exchange genetic information.

The speed at which bacteria reproduce is immeasurably faster than that of more complex, eukaryote organisms. Bacteria have a much shorter lifespan as well – but because they can develop very quickly into large colonies given ideal conditions, it is easier to understand bacteria in clusters. Should a single bacterial organism develop a trait that slightly aids its resistance to destructive environmental conditions, it can pass its modified genetic structure on to half of a colony in a matter of hours.

In the meantime the colony is quickly expanding, fully adapted to the environment – soon, however, it has developed more than it can be accommodated. The population will drop quickly in the face of inadaptability. But that (previously mentioned) exterior bacterial organism with the modified trait releases information yielding new growth, allowing the colony to expand further. Itis generally accepted that bacterial colonies will achieve maximum capability – however, through adaptation, the bacterial population will quickly excel once again60. Antibiotics are now sent to destroy the bacteria. Soon they will be obliterated -and now all that remains of the colony are a few choice bacterial organisms. However, an otherwise isolated bacteria enters the system to exchange genetic information with the much smaller bacterial colony, conditions are favorable, the bacteria expand again. Antibiotics are sent again to destroy this colony- but the exterior bacteria, originating in another organism and having developed a resistance to this type of antibody has provided much of the colony with the means for resistance to these antibodies as well. Once again the bacterial culture has expanded having resisted malignant exterior interlopers61. This is how bacteria develop, constantly exchanging nuclear information, constantly able to adapt to innumerable harmful sources. As bacteria are exposed to more destructive forces, the more they develop resistance to, as surely many of the billions of bacteria could develop invulnerability to any threatening exterior sources given ideal environmental conditions.

Punctuated Equilibrium

Recently the concept of punctuated equilibrium, as proposed by American paleontologist Stephen Jay Gould has been the subject of much controversy in the scientific world. Gould advanced the idea that evolutionary changes take place in sudden bursts, and are not modified for long periods of time when they are reasonably adapted to altered environment62.

This almost directly contradicts the older, established Darwinian notions that species evolve through phyletic gradualism, that evolution occurs at a fairly constant rate. Itis not suggested by adherents of the punctuated equilibrium model that pivotal fluctuations in morphology occur spontaneously or in only a few generations changes are established in populations -they argue instead that the changes may occur in but 100 to 1000generations. It is difficult to determine which model could more adequately describe what transpires over the course of speciation and evolution due to gaps in fossil-record, 50 to 100 thousand years of strata often covering deposits bearing fossils. Genetic make-up need not change much for rapid, discernable morphological alterations to detected.

Impartial analysts on the two theories conclude that they are both synonymous with evolutionary theory. Their primary differences entail their emphasis on the importance of speciation long-term evolutionary patterns in the lineage. While phyletic gradualism emphases the significance of changes in a single lineage and the revision of species through slight deviation, punctuated equilibrium emphases the significance of alteration occurring during speciation, maintaining that local (usually small) populations adapt rapidly to the local circumstance in the production of diverse species – some of which acquire the means for supplantation of their ancestors and rampant settlement in many important adaptive breakthroughs. One must consider that Darwin was not aided by the Mendelian theory. Under such circumstances, Darwin would have surely produced an entirely different theory for the inheritance of beneficial traits.

Consider that mutations can presumably occur spontaneously, given the properly modified parent. It can therefore be stated that punctuated equilibrium is probably a more likely explanation a sit does take into account modern cell, and genetic theory.

Phyletic gradualism, while certainly extremely logical is a theory that simply cannot encompass that circumstance in which significant change is recorded over comparatively short periods of time. Both are complementary to be sure, but perhaps one of the two distorts this complementary nature formulating inaccurate assumption.

Value/Limitations: The Theory of Biological Evolution

Whether or not the theory of evolution is useful depends on whether or one values progress above the development of personal notions of existence. Certainly, under the blanket of a superficial American Dream, one would be expected to subscribe to ideals that society, that the state erects. Of course, these ideals focus on the betterment of society as a whole – which now, unfortunately, means power to the state. Everybody is thus caught up in progress, supposedly to “improve the quality of life”, and have been somewhat enslaved by the notion of work.

Work has become something of an idol, nothing can be obtained without work – for the state. Whether one agrees with the thoughtless actions of the elite or not, people are oppressed by conforming to ideals that insist upon human suffering. Someirresponsible, early religious institutions did just that, erecting a symbol of the people’s suffering and forcing them to bow before it. Development of aeronautic, or even cancer research contributes primarily to this ideal of progress.

The development of such theories as biological evolution contributes nothing toward progress. It instills in the people new principles, to dream and develop an understanding of themselves and that which surrounds them ones, freeing their will from that shuffling mass, stumbling as they are herded towards that which will reap for them suffering and pain. The state provides this soulless mass with small pretty trinkets along the way, wheedling and cajoling them with media images of how they should lead their lives – the people respond with regrets.

The modern theory of biological evolution is actually sadly lacking in explanation for exactly how characteristics are passed down to future generations. It is understood how nitrogen bases interact to form a genetic code for an organism – but how the modification that the organism develops, occurs is unknown.

Somehow the organism mutates to adapt to environmental conditions, and then presumably the offspring of this organism will retain these adaptations. Of course, biological evolution can not also explain precisely how the first organisms developed: Generally, the theory accounts for energy and chemical interactions at a level consistent enough to establish a constant flow of said interactions – but even here it falls short. And what of phyletic gradualism? It is completely unable to explain the more sudden mutations that occur…for obvious reasons it cannot explain this (Darwin had any knowledge of genetics), but even punctuated gradualism doesn’t balance this problem. I’m sure there are numerous other problems which can be addressed but these can be dealt with where opinion can be more educated.

Alternate Explanations of Being

Man, it would appear, has always sought meaning for his existence. The development of many theories of existence has been conceived and passed down through the ages. Institutionsconferring single metaphysical and elemental viewpoints have been established, some of which have been particularly irresponsible and oppressive towards the people they were supposed to”enlighten”. Most religious institutions have been used as political tools for means of manipulation of the masses, going back to early Roman days when empower Augustus absorbed Christianity into the Roman worship of the sun, Sol Invectus, asa means of subjugating the commoners to Roman doctrine.

Generally, religious institutions have exploited the people and have been used as excuses for torture, war, mass extermination sand general persecution and oppression of the people it pretends to serve, telling the people they must suffer to reach ultimate transcendent fulfillment. Unfortunately, this oppression continues in today’s modern – even Western – world. There have actually been almost innumerable explanations for the physical presence of a man – these explanations merely been suppressed by the prevailing religious institutions for fear that they will be deprived absolute power over the people…they’re right.

Conclusions

Without Darwin it can be concluded, reasonable interpretation of biological evolution simply would not be.

Natural selection, the process determining the ultimate survival of a new organism, remains the major contributing factor to even the most modern evolutionary theory. The evolutionary process spans over the course of hundreds of thousands of generations, organisms evolving through systematic and dispersive mechanisms of speciation. Recently, heated debate surrounding whether characteristics are passed on in bursts of activity through punctuated equilibrium or at a constant rate through the more traditional phyletic gradualism66. The release of Mendeliantheory into the scientific community filled the primary link missing in Darwin’s theory – how biological characteristics were passed on to future generations. Applications of genetic theory to evolutionary theory, however, are somewhat limited. It is difficult to classify all species even through modern means of paleontology and application to the theory of organic evolution.

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  16. Stansfield, William D.. Genetics 2/ed. New York: McGraw-Hill Book Company, 1983, p.266-287.
  17. Thomas, K.S. H.M.S. Beagle, 1820-1870. Washington: Oxford University Press, 1975.

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Darwinian Theory of Evolution. (2019, Mar 16). Retrieved from https://graduateway.com/darwinian-theory-of-evolution/

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