The Evolution of the Theory of Evolution

The Evolution of the Theory of Evolution

The Galapagos Islands are a unique place on the planet in more than one sense. One of their main claims to fame is the role they played in Charles Darwin’s perceptions on the origins of species, becoming a catalyst in his presentation of the Theory of Evolution.

Contrary to widespread belief, Charles Darwin (1809-1882) didn’t invent the idea of evolution. The idea of evolution had been, in fact, a growing concept in his day, something that was called “descent with modification.”

But Darwin took the merit because he came up with a particular explanation of how evolution takes place. Most of Darwin’s pieces for the jigsaw puzzle of evolution were collected during his five-year Voyage aboard the Beagle (1931-1936).

Darwin’s On the Origin of the Species (1959) was published twenty-four years after he visited the Galapagos. The book was, at the time, the first full exposure that most educated people in Europe and America received in relation to the subject of evolution. It caused such an impact, that Darwin appeared –in the eyes of the public– as the first true exponent of the theory of evolution.

Nonetheless, parallel to Darwin, and having arrived at similar conclusions on his own, history presents Alfred Russell Wallace (1823-1913) as a young British Naturalist who had been collecting biological specimens in Southeast Asia which he was selling to private collectors and museums. A draft paper written by Wallace and presented to Darwin in 1958, convinced Darwin to finally publish his own findings.

Both Wallace and Darwin (at Darwin’s insistence) received the credit for the theory of evolution during the debates carried out at the British Royal Society. But Wallace’s turn to spiritualism later in life, and his activism in the socialist movement during the 1890’s, basically took the spotlight away from him and Darwin was crowned the king of evolutionary theory.

Darwin’s inspiration

Both Darwin and Wallace were greatly influenced by Thomas Malthus (1766-1834), especially by his article “Essay on the Principles of Population,” in which Malthus presented his findings that human populations double every 25 years unless limits in food supply either keep them in check or decimate them. Upon reading this essay, both Wallace and Darwin arrived at the conclusion that a similar process was occurring in animal populations lacking enough water, food, or other resources needed for survival.

Another author of great influence that shaped Darwin’s view of the earth were the early works of Charles Lyell, which Darwin read at the beginning of the Beagle’s voyage, in 1831. Lyell, an English scientist studying the geological deposits in Europe, presented the idea that slow, progressive geological changes had shaped the planet. Forces such as erosion, earthquakes, glacial movements, volcanoes, even the decomposition of plants and animals, were the “creators” of the geological world.

Lyell’s theory of uniformitarianism found resonance in Darwin. He applied a similar concept in his explanation related to evolution. That is, he concluded that evolution is a gradual process occurring throughout animal and plant populations as they adapt to the changes of the surrounding nature. The species most fit the changed environs to survive under gradually new conditions. Only the most fit to survive are “naturally selected” and able to continue existing.

Lyell’s work was in opposition to George Cuvier’s (1769-1832) ideas of catastrophism, that is, that sudden and drastic changes shape the world. Today, enough evidence exists to show that such catastrophes do occur as well every so often, and that they are the cause of massive extinctions.

Other exponents of evolution

Perhaps one of the first scientists to present the theory of evolution was Charles Darwin’s grandfather, Erasmus Darwin (1731-1802). His belief was that all species descended from a common ancestor and that it was due to competition (as related to sexual selection), and to the use and disuse of parts, that species generated new and evolved (better) species. In this sense, Erasmus Darwin was, as it would be called today, of “Lamarckian mindset.” That is, he believed in the teleological idea that species have an unconscious striving towards perfection.

Jean-Baptiste Lamarck (1744-1829), a French bank clerk who collected and studied plants, published an analysis of flora that landed him a job at the botanical garden, which, after the guillotining of the king and queen during the French Revolution, became the National Museum of Natural History.

Lamark’s theory of evolution –now proven false– stated that “acquired characteristics,” that is, “parts,” are passed down from generation to generation. In other words, parts “used or disused” would be passed on and thus shape future generations. This, Lamark claimed, was the cause for the changes occurring in species. The striving towards perfection advocated by Erasmus Darwin was part of Larmark’s explanations as well, something that can be traced all the way back to the days of the Greek Empire.

For and against

With the advent of Judeo-Christianism came also the Theory of Special Creation. That is, that all things and creatures are created by God and have always had the shape that they have today.

This was a widespread view in Medieval days, a way of thinking confused or combined with the idea of spontaneous generation, that is, that certain living things appear from inorganic matter. Spontaneous generation claimed that maggots came from rotting meat, or that frogs appear spontaneously from slime.

The debates just after the discovery of America turned around in terms of finding the exact date of Creation. One of the greatest advocates of the Judeo-Christian posture was James Ussher (1581-1656), the archbishop of Armagh Ireland. He counted the generations presented in the Bible and added them to modern history. Thus, he managed to fix the date of Creation on Monday, October 23, 4000 BC.

The debate between Creationists and Evolutionists continues to this day. On October 22, 1996, Pope John Paul II addressed the Pontifical Academy of Sciences in relation to the theme they had chosen: “the origins of life and evolution.” He said in his discourse that, instead of speaking of the theory of evolution, “we should speak of several theories of evolution.” He also pointed out that with man, “the only creature on earth that God willed for itself,” there exists an ontological difference and a leap that is not explained and thus makes it possible to reconcile the two points of view.

Some Creationists now acknowledge that evolution may be going on, but they also point out that Darwinism isn’t the final explanation for it and that it does not exclude divine intervention, especially not when it comes to human existence.

Scientists of different fields often refer to Darwin’s conclusions as unscientific, claiming that Darwin presented opinions as if these were facts. Others, like Niels Eldredge and Stephen Jay Gould, disagree on the how natural selection occurs. Rather than it being a gradual process affecting a large population, they came up with the theory of “Punctuated Equilibria.” Their main argument is that speciation –the formation of new biological species— occurs by reproductive isolation of a small group rather than by whole populations of a given species.

Modern Synthesis, Mendelian Inheritance and genetics

There has been a reformulation of Darwin’s theory into what is know as the Modern Synthesis. Modern Synthesis claims that the most apt organisms tend to have the highest chances of survival and of passing this down their lineage. In other words, Modern Synthesis is a blend of neo-Darwinism (which rejected the “inheritance of acquired characteristics”) and Mendelian Inheritance.

Mendelian Inheritance is the result of the re-discovery of the experiments of Gregor Mendel (1822-1884). Gregor Mendel was a Central European monk who discovered, between 1856 and 1863, that by selective plant breeding he could recombine parental traits and pass them on to their offspring. Neither Darwin nor Wallace had been aware of Mendel’s discoveries, unearthed long after Mendel’s death at the beginning of the twentieth century.

In light of the developments that led to the theory presented by Darwin’s On The Origin Of The Species and of what has been happening since then, it can be asserted that evolution has been in a constant process of evolution, and that this process hasn’t ended yet.

Not always a fight for survival

One of the least known counter-arguments to Darwinism is the standpoint presented by Petr Kropotkin in his book Mutual Aid (1902).

Kropotkin had traveled to Siberia at the age of nineteen, that is, to an environment were life was far from easy. What he saw there differed from Darwin’s inspirational experiences during his trip to the tropics aboard the Beagle. The Galapagos had given Darwin the material for presenting a case in favor of evolution, but his other experiences on the South American mainland, so full of life and opulent vegetation complemented his Malthusian viewpoints based on a fight for survival.

Thus, the geographical differences Darwin and Kropotkin were exposed to, brought to light facets of evolution that seemed to oppose each other —and exclude each other— completely.

In short, Darwin had witnessed areas with high population densities due to the abundance in food sources that resulted in intense competition for space. Kropotkin, on the other hand, had experienced the barren terrains with chronic under-population, where animals had to aid each other –as indeed they often do in nature, cooperation being part of the lives of many species, from ants to beavers to horses and other animals making protective rings to safeguard the weak and young in their midst– in order to survive as a species.

Where Darwin found rivalry, Kropotkin found communion among animals. Where Thomas Huxley (‘Darwin’s Bulldog’, 1825-1895) saw social morality as humanity’s saving grace —unlike what purportedly goes on in the animal kingdom—, Kropotkin proclaimed that animal existence contained an inherent communal principle.

Though Kropotkin’s book contained serious flaws of analysis and examples that weren’t always appropriate, he wasn’t alone in his misgivings related to Darwinism. A whole generation of Russian scientists looked upon British approval of Darwin’s conclusions –competition as the basis for evolution– with discomfort. No doubt politics had a lot to do with this.

Social Darwinism

In lieu of Darwin’s idea that only the fittest survive, Herbert Spencer applied this idea to his elitist views that “might makes right.” And thus Social Darwinism was born. Basically, Social Darwinism stated that it is very natural and very right for the strong to strive at the expense of the weak. This notion gave many an entrepreneur and colonial government an “ethical approval” to an often brutal and usually highly exploitative behavior. This imbued the upper economic classes with a “righteousness of behavior” because now they could, without qualms, consider themselves higher in evolutionary terms.

INFOBOX:

Who was Charles Robert Darwin?

Charles Darwin was born into a rather wealthy family in Shrewsbury, England, in 1809, son to Robert Darwin and Susannah Wedgewood. His father held the largest medical practice on the outskirts of London, his mother came from a family of affluent pottery manufacturers. He went to university at the age of 16 to study medicine (1825-27), but after a two year, uninspired spree, he went to Cambridge to study theology. Here he was introduced to Adam Sedgewick’s scientific ideas about geology, and the theories of the reknown botanist John Henslow, not to mention the writings of his own grandfather, Erasmus Darwin.

These influences moved him towards the study of biology rather than the sacred scriptures. To his father’s dismay, he accepted to board the H.M.S. Beagle as companion to Captain Robert Fitzroy, sailing off on special missions, one of them secret. Darwin was 22 at the time. Captain Fitzroy himself was 23 and in charge of two official missions and one unofficial.

One of the official missions was the mapping of the east and west coasts of South America. The other, was to take chronometric readings during their voyage in order to find a way to accurately measure Longitude. This, back in those days, was still a big problem for sailors and a major undertaking of the British Crown in the midst of colonial expansionism.

The unofficial mission was to repatriate Tierra del Fuego natives that had been captured on a previous voyage of the Beagle, on which Fitzroy had been first mate (the captain had committed suicide). Loneliness and isolation, and a highly-strung as well as unstable emotional state, moved Fitzroy to find a travel companion, and who better than an English gentleman versed in science and of good social standing: Charles Darwin.

The H.M.S. Beagle was a 90-foot ketch with a crew of 74 able seamen. In other words, a tight fit. Darwin, who suffered from serious motion sickness, spent as much time on land as possible. There he usually gathered all kinds of samples, from plants to rocks to bones of birds and animals, which he then took back home to study. It was on the Galapagos Islands that he began to think about the possibility of evolutionary changes. These thoughts, however, he didn’t really dare to make public until twenty-four years later upon receiving an essay written by Alfred Wallace.

Darwin versus Wallace

The argument that as the elder, Darwin should have received most of the credit for the Theory of Evolution, remains controversial. Darwin didn’t seem ready to publish his almost heretical ideas about evolution until he received Wallace’s essay entitled: “On the tendency of varieties to depart indefinitely from the original type.”

Darwin, after receiving Wallace’s paper and before he published his larger piece (On the Origin of the Species by Means Of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life), presented a shorter version of his findings, curiously entitled: “On the tendency of species to form varieties; and on the perpetuation of varieties and species by natural means of selection.”

This essay appeared after having kept Wallace’s text in his hands for several months. Both essays were read at the Linnean Society, but many tend to forget the important role Wallace played in the making public of the Theory of Evolution.

Darwinism versus Social Darwinism

Many confuse Darwinism as a scientific explanation of biological evolution with Social Darwinism, which is a socio-political movement used to justify numerous exploits, presenting colonialism as natural and inevitable. It is clear that Social Darwinism borrows many scientific ideas from Darwin’s findings, yet it is not based on any scientific proof. Nevertheless, Social Darwinism is still in vogue in many schools of thought (perhaps unconsciously so), especially those that present competition as the best means –and the excuse– for growth and inevitable development.

Date of Creation

Dr. Charles Lightfoot of Cambridge in England was the scholar who, after countless debates surrounding Ussher’s methods of calculation, presented a more precise figure for Creation: 9 AM, October 23, 4000 BC.

Niels Eldredge and Stephen Jay Gould’s theory of “Punctuated Equilibria”

New species arise by the splitting lineages. New species develop rapidly. A small sub-population of the ancestral form gives rise to the new species. The new species originates in a very small part of the ancestral species geographic extent –in an isolated area at the periphery of the range.

A geographic phenomenon

A treatise of Russian Natural Science entitled Darwin without Malthus, written by Daniel Todes, portrayed the reason for the difference in views in regards to the process of evolution —cooperation instead of competition— as being a geographical phenomenon.

Frans De Waal

Frans De Waal, a Dutch-born zoologist and ethologist specializing in primate behavior, presents a strong case for the human inheritance of traits such as sympathy and compassion from the animal realm, rather than these being an exclusivity of human development. His book Good Natured: The Origins Of Right And Wrong In Humans And Other Animals (1996), presents a detailed study on how such traits, apparently so-called “ethical behavior,” have been present in both humans and animals alike for countless millennia.

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