Evolutionary theory h Darwin table. Darwin's contribution to biology briefly. What contribution did Charles Darwin make to the development of biology? The evolutionary views of Alfred Wallace
Charles Robert Darwin is a naturalist, a pioneer of the theory of the origin of life on Earth from a common ancestor, through the evolution of each species. Author of the book "The Origin of Species", the theory of the origin of man, the concepts of natural and sexual selection, the first ethological study "The Expression of Emotions in Man and Animals", the theory of the causes of evolution.
Charles Darwin was born on February 12, 1809 in Shropshire (England) at the Darwin estate, Mount House, in Shrewsbury. Robert Darwin, the boy's father, physician and financier, son of the learned naturalist Erasmus Darwin. Mother Susan Darwin, nee Wedgwood, daughter of artist Josiah Wedgwood. There were six children in the Darwin family. The family attended the Unitarian Church, but Charles's mother was a parishioner of the Anglican Church before marriage.
In 1817, Charles was sent to school. Eight-year-old Darwin became acquainted with natural history and took his first steps in collecting. In the summer of 1817, the boy's mother died. The father sent his sons Charles and Erasmus in 1818 to a boarding school at the Anglican Church - the Shrewsbury School.
Charles did not make progress in his studies. Languages and literature were hard. The main passion of the boy is collecting collections and hunting. The moralizing of his father and teachers did not force Charles to take up his mind, and in the end they gave up on him. Later, young Darwin had another hobby - chemistry, for which Darwin was even reprimanded by the head of the gymnasium. Charles Darwin graduated from the gymnasium with far from brilliant results.
After graduating from high school in 1825, Charles, along with his brother Erasmus, entered the University of Edinburgh, the faculty of medicine. Before entering, the young man worked as an assistant in his father's medical practice.
Darwin studied at the University of Edinburgh for two years. During this time, the future scientist realized that medicine was not his calling. The student stopped going to lectures and became interested in making stuffed animals. Charles' teacher in this matter was the freed slave John Edmonstone, who traveled through the Amazon in the group of the naturalist Charles Waterton.
Darwin made his first discoveries in the anatomy of marine invertebrates. The young scientist presented his work in March 1827 at a meeting of the Pliny Student Society, of which he had been a member since 1826. In the same society, young Darwin became acquainted with materialism. During this time he worked as an assistant to Robert Edmond Grant. He attended a natural history course by Robert Jameson, where he received basic knowledge in geology, worked with collections belonging to the Edinburgh University Museum.
The news of his son's neglected studies did not delight Darwin Sr. Realizing that Charles could not become a doctor, Robert Darwin insisted on his son's admission to Christ's College, Cambridge University. Although visits to the Pliny Society greatly shook Darwin's faith in the dogmas of the church, he did not resist the will of his father and in 1828 withstood entrance exams to Cambridge.
Studying at Cambridge did not fascinate Darwin too much. The student's time was occupied by hunting and horseback riding. A new hobby appeared - entomology. Charles entered the circle of insect collectors. The future scientist became friends with Cambridge professor John Stephens Genslow, who opened the door for the student to wonderful world botany. Genslow introduced Darwin to the leading naturalists of the time.
With the approach final exams Darwin began to force the missed material in the main subjects. Ranked 10th in graduation exam results.
Trips
After graduating in 1831, Charles Darwin remained at Cambridge for some time. He devoted time to studying the works of William Paley's Natural Theology and Alexander von Humboldt's (Personal Narrative). These books gave Darwin the idea of traveling to the tropics to study the natural sciences in practice. To implement the idea of travel, Charles took a course in geology by Adam Sedgwick, and then went with the reverend to North Wales to map rocks.
Upon arrival from Wales, Darwin received a letter from Professor Henslow with a recommendation to Robert Fitzroy, captain of the British Royal Navy expedition ship Beagle. The ship was then setting out on a voyage to South America, and Darwin could take the place of a naturalist in the crew. True, the position was not paid. Charles's father strongly objected to the trip, and only the word "for" Charles's uncle, Josiah Wedgwood II, saved the situation. The young naturalist went on a trip around the world.
Charles Darwin's ship was called the Beagle The journey began in 1831 and ended on October 2, 1836. The crew of the "Beagle" carried out work on the cartographic survey of the coasts. Darwin at this time was busy collecting exhibits on the shore for a collection of natural history and geology. He kept a full record of his observations. At every opportunity, the naturalist sent copies of the records to Cambridge. During the journey, Darwin collected an extensive collection of animals, a large proportion of which was assigned to marine invertebrates. Described the geological structure of a number of coasts.
Near the islands of Cape Verde, Darwin made a discovery about the influence of the time interval on geological changes, which he applied in writing works on geology in the future.
In Patagonia, he discovered the fossilized remains of an ancient mammal Megatherium. The presence next to it in the rock of modern mollusk shells testified to the recent extinction of the species. The discovery aroused interest in the scientific community of England.
The study of the stepped plains of Patagonia, revealing the ancient layers of the Earth, led Darwin to the conclusion that the statements in Lyell's work "on the permanence and extinction of species" were incorrect.
Off the coast of Chile, the Beagle team caught an earthquake. Charles saw the earth's crust rising above sea level. In the Andes, he found the shells of marine invertebrates, which led the scientist to speculate about the emergence of barrier reefs and atolls due to tectonic movement earth's crust.
In the Galapagos Islands, Darwin noticed the differences between local animal species from mainland relatives and representatives of neighboring islands. The object of the study was the Galapagos tortoises and mockingbirds.
In Australia, the outlandish marsupials and platypuses seen were so different from the animal world of other continents that Darwin seriously thought about another "creator".
With the Beagle team, Charles Darwin visited the Cocos Islands, Cape Verde, Tenerife, Brazil, Argentina, Uruguay, and Tierra del Fuego. Based on the information collected, the scientist created the works Diary of a Naturalist's Research (1839), Zoology of Travel on the Beagle Ship (1840), Structure and Distribution of Coral Reefs (1842). He described an interesting natural phenomenon - penitentes (special ice crystals on the glaciers of the Andes).
After returning from his travels, Darwin began collecting evidence for his theory of species change. Living in a deeply religious environment, the scientist understood that with his theory he was undermining the accepted dogmas of the existing world order. He believed in God as the highest being, but was completely disillusioned with Christianity. His final departure from the church came after the death of his daughter Ann in 1851. Darwin did not stop helping the church and providing support to the parishioners, however, while attending a church service with his family, he went for a walk. Darwin called himself an agnostic.
In 1838 Charles Darwin became secretary of the Geological Society of London. He held this post until 1841.
Doctrine of descent
In 1837, Charles Darwin began keeping a diary classifying plant varieties and domestic animal breeds. In it, he entered his thoughts on natural selection. The first notes on the origin of species appeared in 1842.
"The Origin of Species" is a chain of arguments supporting the theory of evolution. The essence of the doctrine is the gradual development of species populations through natural selection. The principles set forth in the work have received the name "Darwinism" in the scientific community.
In 1856, preparations began for an expanded version of the book. In 1859, 1,250 copies of The Origin of Species by Means of Natural Selection, or the Preservation of Favored Breeds in the Struggle for Life, saw the light of day. The book sold out in two days. During Darwin's lifetime, the book was published in Dutch, Russian, Italian, Swedish, Danish, Polish, Hungarian, Spanish and Serbian. Darwin's works are being republished and are still popular today. The theory of the natural scientist is still relevant and is the basis of the modern theory of evolution.
Another important work of Darwin is The Descent of Man and Sexual Selection. In it, the scientist developed a theory about a common ancestor in humans and modern apes. The scientist conducted a comparative anatomical analysis, compared embryological data, on the basis of which he showed the similarity between humans and monkeys (simial theory of anthropogenesis).
In On the Expression of the Emotions in Man and Animals, Darwin described man as part of an evolutionary chain. Man, as a living organism, has developed from a lower animal form.
Personal life
Charles Darwin married in 1839. He took marriage seriously. Before making a decision, I wrote down all the pros and cons on a piece of paper. After the verdict "Marry-Marry-Marry" on November 11, 1838, he proposed to his cousin Emma Wedgwood. Emma is the daughter of Josiah Wedgwood II, Charles's uncle, Member of Parliament and owner of a porcelain factory. At the time of the wedding, the bride was 30 years old. Prior to Charles, Emma had rejected marriage proposals. The girl corresponded with Darwin during the years of travel to South America. Emma is an educated girl. Wrote sermons for rural school, studied music in Paris with Frederic Chopin.
The wedding took place on January 29th. The wedding was held in the Anglican Church by the brother of the bride and groom, John Allen Wedgwood. The newlyweds settled in London. On September 17, 1842, the family moved to Down, Kent.
Emma and Charles had ten children. Children have reached a high position in society. Sons George, Francis and Horace were members of the English Royal Society.
Three babies have died. Darwin associated the sickness of children with the kinship between himself and Emma (the work "Soreness of descendants from inbreeding and the advantages of distant crossings").
Death
Charles Darwin died at the age of 73 on April 19, 1882. Buried in Westminster Abbey.
After her husband's death, Emma bought a house in Cambridge. Sons Francis and Horace built houses nearby. The widow lived in Cambridge during the winter. Moved to the family estate in Kent for the summer. She died October 7, 1896. She was buried in Downe, next to Darwin's brother Erasmus.
- Charles Darwin was born on the same day as.
- In the photo, Darwin looks like.
- On the Origin of Species did not become so titled until the sixth edition.
- Darwin recognized new species of animals from a gastronomic point of view: he tasted dishes from armadillos, ostriches, agoutis, and iguanas.
- Many rare species of animals are named after the scientist.
- Darwin never renounced his beliefs: until the end of his days, living in a deeply religious family, he was a man of doubts about religion.
- The journey of the Beagle stretched out instead of two years for five.
Story evolutionary ideas. The significance of the works of K. Linnaeus, the teachings of J. B. Lamarck
Evolution- the irreversible historical development of living nature.
2. Fill in the table.
History of the development of evolutionary ideas (until the twentieth century).
3. What are the strengths and weak sides systems of the organic world of K. Linnaeus?
Developed the first relatively successful artificial system of the organic world. He took the form as the basis of his system and considered it an elementary unit of living nature. Related species united them into genera, genera into orders, orders into classes. Introduced the principle of binary nomenclature into taxonomy.
The disadvantages of the Linnaean system were that, when classifying, he took into account only 1-2 signs (in plants - the number of stamens, in animals - the structure of the respiratory and circulatory system), which do not reflect true kinship, so distant genera ended up in the same class, and close ones - in different ones. Linnaeus considered species in nature to be immutable, created by the Creator.
4. Formulate the main provisions of the evolutionary theory of J. B. Lamarck.
Points of Lamarck's evolutionary theory:
The first organisms originated from inorganic nature by spontaneous generation. Their further development led to the complication of living beings.
All organisms have a striving for perfection, originally laid down in them by God. This explains the mechanism of complication of living beings.
The process of spontaneous generation of life continues constantly, which explains the simultaneous presence in nature of both simple and more complex organisms.
The law of exercise and non-exercise of organs: the constant use of an organ leads to its increased development, and non-use leads to weakening and disappearance.
The law of inheritance of acquired characteristics: changes that have arisen under the influence of constant exercise and non-exercise of the organs are inherited. So, Lamarck believed, formed, for example, the long neck of the giraffe and the blindness of the mole.
He considered the direct influence of the environment to be the main factor of evolution.
5. Why did the contemporaries criticize the theory of J. B. Lamarck?
Lamarck erroneously believed that a change in the environment always causes beneficial changes in organisms. In addition, he could not explain where the “striving for progress” comes from in organisms, and why it is necessary to consider the hereditary property of organisms to respond expediently to external influences.
6. What progressive features do modern evolutionary scientists see in the theory of J. B. Lamarck?
In the book "Philosophy of Zoology" Lamarck suggested that during life each individual changes, adapts to the environment. He argued that the diversity of animals and plants is the result historical development organic world - evolution, which he understood as a stepwise development, a complication of the organization of living organisms from lower to higher forms. He proposed a peculiar system of organizing the world, placing related groups in it in ascending order - from simple to more complex, in the form of a "ladder".
The evolutionary doctrine of Ch. Darwin
1. Give definitions of concepts.
Factors of evolution- according to Darwin, this is natural selection, the struggle for existence, mutational and combinative variability.
artificial selection- the choice by a person of the most economically or decoratively valuable individuals of animals and plants in order to obtain offspring from them with the desired properties.
2. What aspects of the social and scientific situation in the early and middle of the 19th century contributed, in your opinion, to the development of evolutionary theory by Charles Darwin?
By the middle of the XX century. a number of important generalizations and discoveries were made that contradicted creationist views and contributed to the strengthening and further development of the idea of evolution, which created the scientific prerequisites for the evolutionary theory of Charles Darwin. This is the development of systematics, Lamarck's theory, Baer's discovery of the law of germline similarity and the achievement of other scientists, the development of biogeography, ecology, comparative morphology, anatomy, the discovery cell theory, as well as the development of breeding and the national economy.
3. Fill in the table.
Stages life path Ch. Darwin
4. Formulate the main provisions of the evolutionary teachings of Ch. Darwin.
1. Organisms are changeable. It is difficult to find such a property by which individuals belonging to a given species would be completely identical.
2. Differences between organisms are, at least in part, inherited.
3. Theoretically, populations of plants and animals tend to multiply exponentially, and theoretically any organism can fill the Earth very quickly. But this does not happen, since life resources are limited, and the strongest survive in the struggle for existence.
4. As a result of the struggle for existence, natural selection occurs - individuals with properties that are useful under given conditions survive. Survivors transmit these properties to their offspring, that is, these properties are fixed in a series of subsequent generations.
5. Fill in the table.
Comparative characteristics of the evolutionary theories of J. B. Lamarck and C. Darwin
6. What is the significance of the evolutionary teachings of Ch. Darwin for the development of biological science?
Darwin's teaching made it possible to harmonize disparate knowledge about the laws that govern the organization of life on our planet. In the past century, Darwin's evolutionary theory was developed and concretized thanks to the creation of the chromosome theory of heredity, the development of molecular genetic research, taxonomy, paleontology, ecology, embryology, and many other areas of biology.
1. Define the concept.
Struggle for existence- this is one of the driving factors of evolution, along with natural selection and hereditary variability, a set of diverse and complex relationships that exist between organisms and environmental conditions.
2. Fill in the table.
The struggle for existence and its forms
3. Which of the forms of the struggle for existence is, in your opinion, the most intense? Explain the answer.
Intraspecific struggle proceeds most acutely, since individuals have the same ecological niche. Organisms compete for limited resources - food, territorial, males of some animals compete with each other for the fertilization of the female, as well as other resources. To reduce the severity of intraspecific struggle, organisms develop various adaptations - the delimitation of individual areas, complex hierarchical relationships. In many species, organisms at different stages of development occupy different ecological niches, for example, beetle larvae live in the soil, and dragonflies live in water, while adults inhabit the ground-air environment. Intraspecific struggle leads to the death of less adapted individuals, thus contributing to natural selection.
Natural selection and its forms
1. Give definitions of the concept.
Natural selection- this is the selective reproduction of genotypes that best meet the prevailing living conditions of the population. That is, the main evolutionary process, as a result of which the number of individuals with maximum fitness (the most favorable traits) increases in the population, while the number of individuals with unfavorable traits decreases.
2. Fill in the table.
3. What is the consequence of natural selection?
Change in the composition of the gene pool, removal from the population of individuals whose properties do not provide advantages in the struggle for existence. The emergence of adaptations of organisms to environmental conditions.
4. What, in your opinion, is the creative role of natural selection?
The role of natural selection is not only to weed out non-viable individuals. The form that drives it retains not individual features of the organism, but their entire complex, all combinations of genes inherent in the organism. Selection creates adaptations and species, removing from the gene pool populations that are inefficient from the point of view of survival genotypes. The result of its action are new types of organisms, new forms of life.
message about, English scientist and naturalist, you will read in this article.
Charles Darwin contribution to science
He created the evolutionary theory, substantiating it scientifically. Charles Darwin's doctrine of natural selection is set forth in his main work, The Origin of Species by Means of Natural Selection, published in 1859.
Charles Darwin's contributions to biology
The English scientist believed that the struggle for existence and hereditary variability are driving forces evolution. Struggle causes natural selection, during which only the fittest individuals of a particular species survive. In the process of reproduction, their hereditary changes are summed up and accumulated. Today Darwin's doctrine is called "Darwinism" or "evolutionary doctrine". But let's take a closer look at how the naturalist Charles Darwin came to discover his theory.
First of all, he studied the achievements of his predecessors and made several trips to South America in order to study the geological deposits of the skeletons of giant edentulous animals. The scientist also studied the ancestors of brusks on the Galapagos Islands, who flew here from the mainland and adapted to new food sources for them: nectar, hard seeds and insects. Charles Darwin thought that species changes in animals are due to their adaptation to new living conditions. Returning home, he set himself the task of solving the question of the origin of species. In 1859, in his book The Origin of Species by Means of Natural Selection, he summarized the collected empirical material on biology and breeding practice, based on observations made during his travels. Then there were two more books with factual materials: "Change in Domestic Animals and Cultivated Plants" (1868), "The Descent of Man and Sexual Selection" (1871). The theory of natural selection put forward by him, when stronger and more adapted species survive in the world, made him an authoritative scientist in the world of science.
The basis of Darwin's theory is the property of heredity: the ability of an organism to repeat the type of metabolism of its predecessors in individual development. This ensures the constancy and diversity of life forms. Darwin even came up with the so-called motto for his theory - "the struggle for existence." This concept is used by scientists to describe the interaction between organisms and abiotic conditions. These conditions lead to the fact that only the fittest individuals survive, and the less fit die.
Achievements of Charles Darwin
In addition to the theory of evolution, he interested in studying psychology. In 1872 and 1877 he published the works "On the Expression of Sensations in Animals and Man", "Instinct", "A Biographical Sketch of a Child". The scientist was the first to use the objective method of study in psychology as a form of observation rather than experiment. The English naturalist was also the first to investigate the mental phenomenon of the expression of emotions through the principle of objective analysis.
Doctor of Physical and Mathematical Sciences"Science first hand" №4(34), 2010
about the authorDoctor of Physical and Mathematical Sciences, Honored Professor of the University. George Mason (USA), foreign member of the National Academy of Sciences of Ukraine, Academician of the New York Academy of Sciences, Honorary Professor of the Siberian Branch of the Russian Academy of Sciences, Lomonosov Moscow State University. Lomonosov and Jerusalem University. In 1961–1970 worked at the institutes of the Academy of Sciences and the Academy of Medical Sciences of the USSR, from 1970 to 1978 at VASKhNIL. In 1974, he founded the All-Union Scientific Research Institute of Applied Molecular Biology and Genetics, VASKhNIL, in Moscow. Sphere scientific interests: the effect of radiation and chemicals on genes, the study of the physicochemical structure of DNA, repair in plants, the effect of radioactive contamination on the human genome. He was awarded the Gregor Mendel International Medal and the N. I. Vavilov Silver Medal. Author of more than 20 books, including those on the history of science, published in Russia, the USA, England, Germany, Vietnam and the Czech Republic, editor-in-chief of the 10-volume encyclopedia " Modern natural science", member editorial board magazine "SCIENCE first hand" |
In 1859 Charles Darwin published his book The Origin of Species by Means of Natural Selection, or the Preservation of Favorable Breeds in the Struggle for Existence. It immediately became a bestseller, topping the list worldwide. famous books and bringing its author the laurels of the only discoverer of evolutionary theory. However, the latter is not only inaccurate, but also historically unfair in relation to other scientists, predecessors and contemporaries of Darwin, which is proved in the next “evolutionary essay” published in our journal from the forthcoming book by the famous scientist and historian of science V. N. Soifer “ The evolutionary idea and the Marxists.
Charles Darwin was born on February 12, 1809, the year of the publication of Jean Baptiste Lamarck's Philosophy of Zoology, in which the first evolutionary theory was presented in detail and in detail.
Darwin did not shine at school. Things were also not going well at the college, and in the end his father sent him away - to Scotland, where in October 1825 the 16-year-old boy began to study at the medical faculty of the University of Edinburgh (such a choice of his son's future specialty was not accidental - his father was a successful doctor ). Two years later, it became clear that a doctor from Charles would not work. Followed new translation- this time to another famous university, Cambridge, but already to the theological faculty. Charles himself recalled studying there: “... the time that I spent in Cambridge was seriously lost, and even worse than lost. My passion for rifle shooting and hunting... led me to a circle... of young people of not very high morals... Often we drank too much, and then cheerful songs and cards followed. ... I know that I should be ashamed of the days and evenings spent in this way, but some of my friends were such nice fellows, and we all had so much fun that I still remember this time with pleasure.
Finally, in May 1831, Darwin passed the examination for a bachelor's degree. He was supposed to study at the faculty for two more semesters, but events turned out differently. Taking advantage of a rare opportunity, he was hired, against his father's wishes, on the Beagle, which was sailing around the world under the command of Captain Robert Fitz-Roy. As a naturalist, Darwin's duties included collecting animals, plants, and geological specimens. In five years Darwin visited South America, the islands Pacific Ocean, New Zealand, Australia and other points of the globe.
The five-year round-the-world trip came to an end on October 2, 1836. Now Darwin had to start describing the collected collections and publishing data on the trip. Three years later, his first book was published - "Journey on the Beagle Ship" (or "Research Diary"), which immediately brought great popularity to the young author. Darwin had a rare gift for storytelling, able to color details and events that were not even very entertaining at first sight.
It all started with Malthus?
When did Darwin first think about the problems of evolution? He himself mentioned many times that he came to his evolutionary hypothesis in 1842 and that he was inspired by the book of the great English economist Thomas Robert Malthus, An Essay on the Law of Population (1798). Malthus argued that the population on Earth is growing exponentially over time, and the means of subsistence - only in arithmetic. Darwin claimed that this thesis struck him, and he translated this pattern to all of nature, assuming that there is always a struggle for existence in it, since there are not enough sources of food and habitat for all those who are born.
The thesis about the existence of such a struggle between representatives of the same species ( intraspecific struggle), as well as between individuals different types (interspecific struggle), was Darwin's major innovation. He stated that evolution occurs due to the selection of individuals better adapted to the external environment ( natural selection). If there really is not enough place under the sun for all those who are born, and the weak die in competition with the strong, then if some organism accidentally turns out to be more adapted to the environment, it will be easier for it to survive and give more offspring. If the improved trait is preserved by the descendants of the lucky one, then they will begin to crowd out relatives less adapted to such an environment, and multiply faster. Nature will take a small step forward, and there, you see, an even more lucky lucky person with an even more perfect structure will appear. And so - millions of years, while there is life on Earth.
Darwin, he says, began to think about the problems of species variability already during the voyage on the Beagle: “I came to the conclusion that species probably change, from data on geographical distribution, etc., but within a few years I stopped impotently before the complete inability to propose a mechanism by which each part of each of the creatures was adapted to the conditions of their life. Lamarck's idea of the gradual improvement of species had by this time become quite popular. Just as a drop hammers a stone, statements about natural development repeated for decades, the appearance of new species did their job and accustomed people to the idea of the admissibility of evolution. It is appropriate to recall Benjamin Franklin with his thesis about a man who turned into such an animal due to the production of tools, and the famous grandfather of Charles, Erasmus Darwin, a doctor and publicist, who outlined in his essay "Zoonomy, or the Laws of Organic Life" (1795) idea of organic progress.
Darwin repeatedly repeated (including in his declining years in his Autobiography) that the idea of natural selection dawned on him in October 1838, when a book by Malthus fell into his hands. However, he allegedly made the first draft of his hypothesis not at the same time, but only 4 years later, in 1842. This manuscript, often mentioned by Darwin in letters to friends, was not published during his lifetime.
Already after the death of Darwin, his son Francis published the book "Fundamentals of the Origin of Species", in which he included two previously unknown manuscripts of his father - the first draft of the hypothesis mentioned above on 35 pages (allegedly written by his father in 1842) and a more lengthy one (on 230 pages). .) text marked 1844. Why these works were not published during the author's lifetime, although, as we will see later, there was an urgent need for this, it is now hardly possible to find out.
Unpublished manuscripts
By 1842–1844, during the decades that had elapsed since the publication of Lamarck's work on evolution, biology had accumulated many facts that fit perfectly into the mainstream of evolutionary ideas. The idea has become stronger, and the society has matured for its perception.
This is evidenced by another, curious, example. In 1843 and 1845 in England, a 2-volume work by an anonymous author "Traces of Natural History" was published. It outlined the idea of the evolution of the living world, pointed out the relationship between related species, and the role of electricity and magnetism in this process was called as the reason for the change in species.
The author drew the following analogy: metal filings form a characteristic pattern of a branched plant stem around one end electrical conductor or the poles of a magnet and a picture, more like a root of a plant, around another. Therefore, it cannot be ruled out that plants arose precisely in this way, because electrical forces took part in their formation. Despite such superficial judgments, the author created a work that was read with unflagging interest.
One of Darwin's friends, writer and publicist Robert Chambers, sent him a copy of the sensational book, and Darwin read it with interest. Six years after the publication of the book, it became clear that the same Chambers was its author.
By 1844, there is a letter from Darwin that sheds light on the fact that it was in this year that he himself began to attach great importance to his reflections on evolution, which was not the case before. On June 5, 1844, he wrote a long letter to his wife Emma, in which he stated in lofty terms his will: in the event of his sudden death, to spend 400 pounds on finishing the just completed manuscript on evolution (the task was detailed - to select the proper examples from books marked by Darwin, edit the text, etc.). On the other hand, it was in January of that year, in a letter to the botanist Joseph Hooker, son of the director of the Royal Botanic Gardens and son-in-law of the then patriarch of geology, Charles Lyell, that Darwin was reflecting on the problem of species variability.
Why did Darwin suddenly decide to address his wife with a special message? He really complained about his health during these years (the diagnosis was not made, and he remained ill for another 40 (!) years). It would seem that if he so valued his idea of evolution that he was ready to spend money on paying fees from the legacy he left, then he would have to spend all available strength and time on bringing the main work to final stage. But nothing of the sort happened. One after another, he published thick books about anything but evolution. In 1845, the second, revised edition of the Beagle Travel Diary was published, in 1846 - a volume on geological observations in South America, in 1851 - a monograph on barnacles, then a book on sea ducks, etc. And the essay on evolution lay motionless. What was Darwin waiting for? Why was he afraid to betray his work to the criticism of colleagues? Maybe he was afraid that someone would see in his work borrowing from other people's works without reference to the true authors?
What Darwin did, however, was to frequently remind his high-ranking friends in letters that he used all his free time to think about the problem of evolution. Some of Darwin's addressees were aware of his main thesis in the most in general terms: for all those born there are not enough supplies of food, water and other means of subsistence, only those who have the potential for survival are kept alive. It is they who ensure progress in the living world.
Edward Blyth and his idea of natural selection
Darwin's supporters later explained his strange slowness with the publication of a work on evolution by the fact that he was absolutely convinced that this idea could not have occurred to anyone, which is why there was no reason to hurry with the publication of the hypothesis, although friends urged Darwin to printing this work. This became clear from the surviving correspondence published after Darwin's death (son Francis reported that his father more than once carefully looked through all his correspondence and selectively burned some of the letters).
However, it is unlikely that only unshakable confidence in his originality explains such behavior of Darwin. In 1959, during the celebration of the centennial anniversary of the publication of The Origin of Species, University of Pennsylvania anthropology professor Lauren Eisley stated that Darwin had other reasons for delaying publication of the evolutionary hypothesis for nearly twenty years. According to Eisley, who did a great deal of research work, Darwin did not come up with the idea of the struggle for existence on his own, but borrowed it, and not at all from the economist Malthus, but from the famous biologist Edward Blyth in those years, who was personally close to Darwin.
Blyth was a year younger than Darwin, grew up in a poor family and, due to difficult financial situations, could only finish a regular school. To provide for himself, he was forced to go to work, and spent all his free time reading, diligently visiting the London British Museum. In 1841 he received a position as curator of the Museum of the Royal Asiatic Society in Bengal and spent 22 years in India. Here he carried out first-class studies of the nature of Southeast Asia. In 1863, due to a sharp deterioration in his health, he was forced to return to England, where he died in 1873.
In 1835 and 1837 Blyth published two articles in the Journal of Natural History in which he introduced the concepts of the struggle for existence and the survival of the more adapted to the environment of existence. However, according to Blyth, selection is not in the direction of ever more improved creatures, acquiring properties that give them advantages over already existing organisms, but quite differently.
The task of selection, according to Blyth, is the preservation of the invariance of the main features of the species. He believed that any new changes in organs (now we would call them mutations) cannot bring anything progressive already. existing species well adapted for millions of years to the external environment. Changes will only disrupt the well-established mechanism of interaction between the environment and organisms. Therefore, all newcomers, inevitably spoiled by the disorders that have arisen in them, will be cut off by selection, will not withstand competition with well-adapted typical forms, and will die out. Thus Blyth applied the principle of selection to the wild, although selection was given a conservative rather than a creative role.
Darwin could not be unaware of Blyth's work: he held in his hands the issues of journals with his articles and quoted them. He wrote, and more than once, that he carefully and carefully followed all the publications concerning the development of life on Earth, and especially those close to him in spirit. He also cited many other works of Blyth, paying tribute to the merits of his colleague, so he could not get past his works on natural selection. However, he never referred to the article in which Blyth clearly and clearly stated the idea of the struggle for existence and natural selection.
Being proud and, as Eisley and a number of other historians believed, obsessed with the mania of not shared glory with anyone, Darwin could take advantage of Blyth's fundamental provisions, after which he began to put his records in order. By 1844, he really could have prepared a rather voluminous manuscript on evolution, but, realizing the lack of originality of his work on the cornerstone issue of natural science, he waited, dragged out time, hoping that some circumstances would change something in the world and allow him to "save face ". That is why in his Autobiography he repeated once again: the only book of Malthus served as an impetus for him to think about the role of natural selection. It was safe to refer to an economist, rather than a biologist, who spoke about natural selection in the world of living beings a few years earlier, because the priority in applying economic analysis to the situation in the biological world remained with the biologist, that is, with him.
But even in this statement, meticulous historians found a stretch: although Darwin indicated the exact date when he read the book of Malthus (October 1838), but neither in the essay of 1842, nor in the more voluminous work of 1844, does he refer to Malthus, as he never referred to the one who pushed him to the idea of evolution, and in the place where he mentioned him, it was not at all about the idea of competition.
Eisley found several more similar cases when Darwin treated his direct predecessors indelicately and thereby partly confirmed the correctness of the opinion expressed back in 1888 by Professor Hughton from Dublin about Darwin's views on the origin of species: “Everything that was new in them was wrong, and what was right was already known.
Apparently, this explains the mysterious fact of Darwin's unwillingness to publish his work on the origin of species for almost 20 years.
The evolutionary views of Alfred Wallace
Perhaps this work would have continued to remain in Darwin's chest, if one of the days there had not been an event that forced him to urgently change his position. In 1858, he received by mail the work of his compatriot, Alfred Wallace, who was at that moment away from England. In it, Wallace expounded the same idea about the role of natural selection in progressive evolution.
From reading Wallace's work, Darwin realized that his competitor had developed the hypothesis of evolution even more extensively than himself, since he included in his analysis not only material on domestic animals, which Darwin had mainly used, but also gathered facts from the wild. Darwin was particularly struck by the fact that Wallace's main formulations were stated in the same words as in his "Evolutionary Outline", and it was Wallace who referred to Malthus.
How could it be that a competitor described the same thing? Alfred Russel Wallace (1823-1913) for many years collected scientific collections on expeditions to the Amazon and Rio Negro rivers, the Malay Archipelago and other places (he collected a collection containing 125 thousand botanical, zoological and geological specimens; compiled dictionaries of 75 adverbs, etc.). Wallace began to think about the problem of the origin of species almost simultaneously with Darwin. In any case, already in 1848, in a letter to his friend, the traveler Henry Bates, he wrote: "I would like to collect and thoroughly study the representatives of any one family, mainly from the point of view of the origin of species."
It is strange that researchers of Darwinism rarely mention the most important fact for understanding the formation of Wallace's evolutionary views, that in September 1855, four years before the first edition of Darwin's On the Origin of Species, Wallace published in " Annals and Magazine of Natural History» an article entitled "On the law governing the emergence of new species." In it, Wallace not only made a statement about the existence of a process of evolution of species, but also pointed out the role of geographical isolation in the development of new varieties. He even formulated the law: "The appearance of each species coincides geographically and chronologically with the appearance of a species very close to it and preceding it." His other thesis was also significant: "Species are formed according to the plan of the previous ones." He based these conclusions not only on data from studies of collections of contemporaneous species, but also on fossil forms.
A. Wallace, who knew well wildlife, drew examples from his expeditionary observations. In the introduction to his book Darwinism... (1889), he writes: “The weak point in Darwin's writings has always been considered that he mainly based his theory on the phenomena of external variability of domesticated animals and cultivated plants. Therefore, I tried to find a solid explanation for his theory in the facts of the variability of organisms in natural conditions.
Wallace, as usual in the scientific community, sent his article to fellow biologists, including Darwin, whom he highly appreciated for describing the journey on the Beagle. A traveler and naturalist, Wallace was well aware of the daunting task of describing the monotonous journeys from place to place and the repetitive activities of the day to day. Two prominent scientists - Lyell and Blyth - also drew Darwin's attention to Wallace's article, as Darwin reported in a letter to Wallace dated December 22, 1857.
Darwin spoke positively of Wallace's work, and from that time a correspondence began between them. But Darwin, deliberately or unwittingly, dampened Wallace's energy regarding further reflection on the problem of the origin of species, when in one of his letters, as if by chance, he informed him that he had been working on the same problem for a long time and wrote big book about the origin of species. This message had an effect on Wallace, as he wrote in a letter to Bates: “I am very pleased with Darwin's letter in which he writes that he agrees with 'almost every word' of my work. Now he is preparing his great work on species and varieties, for which he has been collecting material for 20 years. He can save me the trouble of writing further about my hypothesis ... in any case, his facts will be placed at my disposal, and I will be able to work on them.
However, as all biographers of Darwin unanimously testify, despite promises, Darwin did not provide his hypotheses and the facts in his hands to Wallace. Thus, the prominent Russian biographer of Darwin A. D. Nekrasov writes: “... Darwin, referring to the impossibility of expressing his views in a letter, kept silent about the theory of selection. Wallace came to the idea of natural selection independently of Darwin... Without a doubt, Darwin in his letters did not say a single word either about the principle of the struggle for existence, or about the preservation of the fittest. And Wallace arrived at these principles independently of Darwin.
So, Wallace himself formulated the hypothesis of natural selection, and this happened on January 25, 1858, when the traveler was on one of the islands of the Moluccas archipelago. Wallace fell ill with a severe fever and, between attacks, suddenly realized how Malthus's discussion of overpopulation and its role in evolution could be applied. After all, if Malthus is right, then the chances for better survival higher in organisms better adapted to the conditions of life! In the "struggle for existence" they will prevail over the less adapted, give more offspring, and due to better reproduction, they will occupy a wider area.
After this insight, in the mind of Wallace, who had pondered the problems of species change for many years, a general picture quickly formed. Since he already had the basic facts at his disposal, it was not difficult for him to hastily sketch out the abstracts of the article and also hastily complete the entire work, giving it a clear title: "On the desire of varieties to infinitely move away from the original type." He sent this article with the first opportunity to Darwin, asking for help with the publication. As Nekrasov wrote, "Wallace sent it to Darwin, hoping that the application of the principle of the 'struggle for existence' to the question of the origin of species would be as news to Darwin as to himself."
However, Wallace's suggestion that Darwin would help popularize his work was a mistake and permanently deprived him of his legitimate priority in publishing the principle of evolution by selecting the organisms most adapted to environmental conditions. Darwin not only did nothing to speed up the publication of Wallace's work, but also tried to take all measures to assert his primacy.
Hasty publication of Darwin's work
Having received Wallace's work, Darwin realized that he was ahead of him. Significantly, in a letter to Lyell, he confessed: “I have never seen such a striking coincidence; if Wallace had my 1842 manuscript, he could not have done a better abridged review. Even its titles match the titles of my chapters."
Upon learning of what had happened, two friends of Darwin - Charles Lyell and Joseph Hooker, who occupied high position in the scientific circles of England, decided to save the situation and presented to the members of the London Linnean Society both the completed work of Wallace and a short (on two pages) note by Darwin "On the tendency of species to form varieties and species by means of natural selection." Both materials were read on July 1, 1859 at a meeting of the society and then published under that date.
Darwin was not present at the meeting. There were two speakers - Lyell and Hooker. One of them ardently, the other more reservedly told that they were witnesses of Darwin's creative torments and certified by their authority the fact of his priority. The meeting ended in deathly silence. Nobody made any statements.
By the end of the year, Darwin had completed On the Origin of Species and paid for its publication. The book was printed in two weeks; the entire circulation (1250 copies) was sold out in one day. Darwin hurriedly paid for the second edition, and a month later another 3,000 copies went on sale; then came the third edition, corrected and enlarged, then the fourth, and so on. Darwin's name became immensely popular.
Wallace, fully reconciled to the loss of priority, published in 1870 the book “Contribution to the Theory of Natural Selection”, and in 1889 - a huge (750 pages) volume, symbolically titled “Darwinism. An exposition of the theory of natural selection and some of its applications".
The main purpose of these books was to illustrate with examples the principle of better survival of animals and plants better suited to a given environment. Darwin used examples from the domestication of animals, the breeding of livestock breeds, ornamental birds and fish, and the breeding of plant varieties to a greater extent.
It is appropriate to recall that Wallace had earlier (in his 1856 article) rejected the proof of examples of evolution drawn from the sphere of variability of domesticated animals, rightly pointing out that adaptive (adaptive) variability does not exist in domestic animals. After all, it is man who selects the best forms for him, and the animals themselves do not participate in the struggle for existence: “Thus, from observations of varieties of domestic animals, no conclusions can be drawn regarding varieties of animals living in the wild.”
Darwin's relation to Lamarck
Darwin never tired of repeating that his views had nothing in common with Lamarck's, and throughout his life he never ceased to speak ill of his great predecessor. Perhaps the very idea that he was not the first and that 50 years before him the same thoughts had already been expressed by a Frenchman weighed on him.
In the 1840s in letters to Hooker, he wrote about this more than once: “... I don’t know of any systematic writings on this subject, except for Lamarck’s book, but this is real rubbish”; "Lamarck ... damaged the question with his absurd, albeit clever work"; “May Heaven save me from the stupid Lamarckian “striving for progress”, “adaptation due to the slow desire of animals” and other things. True, he was forced to continue the last phrase of the quoted quotations with the words: "But the conclusions I come to do not differ significantly from his conclusions, although the methods of change are quite different."
In one of his letters to Lyell, sent almost twenty years later, he wrote, discussing the significance of his predecessor's work: from which I have not benefited. But I know you took advantage of it more."
In general, as the Russian researcher of Darwinism Vl. Karpov, initially "Lamarck was alien and little understood by Darwin, as a representative of a different mindset, a circle of ideas, a different nationality." Nevertheless, there were more fundamental similarities in the books of Lamarck and Darwin than differences. Both authors were unanimous in the central issue - the proclamation of the principle of the progressive development of species, and both stated that it is the need to better meet the requirements of the external environment that forces species to progress.
Even the main groups of examples used by Darwin coincided with those of Lamarck (breeds of dogs, poultry, garden plants). Only Darwin tried to give as many examples as possible, albeit of the same type, but creating in the reader the impression of solidity, solidity; Lamarck, on the other hand, limited himself to one or two examples for each point.
The extinction of species, according to Darwin, is a phenomenon that correlates with the origin of new species: “Since, over time, new species are formed by the activity of natural selection, others must become more and more rare and, finally, disappear. ... In the chapter devoted to the struggle for existence, we saw that the most fierce competition should occur between forms, the closest - varieties of one species or one genus or genera closest to each other, since these forms will have almost the same structure, common warehouse and habits "
Where Darwin's thinking differed greatly from Lamarck's was in trying to explain the causes of evolution. Lamarck looked for them inside organisms, in the ability inherent in them to change the structure of the body depending on the exercise of the organs (and in the second half of the 19th century this position of Lamarck was regarded as extremely important, because the vast majority of scientists believed that the property of self-improvement is inherent in living beings). Darwin initially proceeded from the fact that the properties of organisms could change due to random causes, and the external environment played the role of a controller, cutting off less adapted individuals. But since Darwin did not understand what could change in organisms, what hereditary structures were, these thoughts of his were entirely hypothetical philosophizing.
The paradox lies in the fact that, starting with a categorical rejection of the "stupid" views of Lamarck, Darwin gradually began to change his views and talk about the possibility of direct inheritance of traits acquired during his life. The main reason for this change was the most important circumstance that interfered with Lamarck, namely: the lack of information about the laws of inheritance of traits, ignorance that there are special structures in the body that carry hereditary information.
However, if at the time of Lamarck science was still far from posing questions related to the discovery of the laws of heredity, and it would be absurd to cast even a shadow of a reproach against Lamarck, then by the time the Origin of Species was published, the situation had changed radically.
Gemmules instead of genes
The first approaches to the knowledge of the laws of heredity, albeit still in a rather amorphous form, developed as a result of the work of the German researcher Josef Gottlieb Kölreuter (1733–1806), who worked for several years in St. Petersburg, and a number of other European scientists. Kölreuther in 1756–1760 conducted the first experiments on hybridization and formulated the concept of heritability.
The Englishman Thomas Andrew Knight (1789–1835), crossing different varieties of cultivated plants, came to the conclusion that in the generations of hybrid plants, the traits by which the original varieties differ among themselves “crumble” and appear individually. Moreover, he noted that there are small individual differences, which are not further "divided" during crossings and retain their individuality in generations. Thus, already in early XIX V. Knight formulated the concept of elementary inherited traits.
Frenchman Auguste Sageret (1763–1851) in 1825–1835 made another important discovery. By following Knight's "elementary signs," he found that some of them, when combined with others, suppressed the manifestation of these signs. So dominant and recessive traits were discovered.
In 1852, another Frenchman, Charles Naudin (1815-1899), studied these two types of traits more closely and, like Sageret, found that in combinations of dominant and recessive traits, the latter cease to appear. However, it is worth crossing such hybrids among themselves, as in some of their descendants they again appear (later Mendel will call this process splitting of characters). These works proved the most important fact - the preservation of hereditary structures that carry information about repressed (recessive) traits even in cases where these traits did not appear outwardly. Naudin tried to discover the quantitative patterns of the combination of dominant and recessive traits, but, having undertaken to follow a large number of them at once, he got confused in the results and could not move forward.
Darwin was well aware of the results of the work of these scientists, but he did not understand their significance, did not appreciate the great benefit that the discoveries of elementary hereditary units brought him, the patterns of their combination and manifestation in descendants. It was necessary to take one more step - to simplify the task and analyze the quantitative distribution of traits in organisms that differ in one or at most two traits, and then the laws of genetics would be discovered.
This breakthrough in science was made by the Czech naturalist, brilliant experimenter Johann Gregor Mendel, who in 1865 published a brilliant work in which he outlined the conclusions of experiments to reveal the laws of heredity. Mendel built the scheme of his experiments precisely by simplifying the problem, when he decided to scrupulously monitor the behavior in crosses, first only one inherited trait, and then two. As a result, he proved, now definitively, the existence of elementary units of heredity, clearly described the rules of dominance, discovered the quantitative patterns of combining units of heredity in hybrids, and the rules for the splitting of hereditary traits.
Darwin, therefore, could discover these laws himself (he advanced in understanding the importance of clarifying the laws of inheritance, moreover, the progress of science at that time was so tangible that what Mendel had done was, in principle, accessible to anyone who thought about the problems of inheritance). But Darwin was not an experimenter. Of course, he could have simply read Mendel's published work in German, however, this did not happen either.
Instead, Darwin set about conjuring up the hypothesis (he pretentiously called it the theory) of pangenesis about how hereditary properties are passed on to descendants. He allowed the presence in any part of the body “... special, independently reproducing and feeding hereditary grains - gemmules, which are collected in the reproductive products, but can be scattered throughout the body ... each of which can restore in the next generation that part that gave them a start."
This hypothesis was by no means original: the same idea was put forward in his 36-volume History of Nature by Georges Louis Leclerc Buffon a hundred years before Darwin. Many eminent scientists, including those who helped Darwin strengthen his priority in proclaiming the role of natural selection in evolution (Hooker and Lyell), advised Darwin not to publish his "theory of pangenesis". He verbally agreed with them, but in fact he decided not to deviate from his own and included the corresponding chapter in the book "Changes in animals and plants under the influence of domestication", published in 1868 (three years later than Mendel's work).
Until the end of his life, Darwin remained convinced that his theory of pangenesis had a great future ahead of it. Although in letters to those on whose help he depended all his life (Lyell, Hooker, Huxley), he coquettishly called this brainchild of his "reckless and unfinished hypothesis", said that "dealing with such speculations is" pure nonsense "" and promised " try to convince himself not to publish "a statement of his" theory ", but he was not going to fulfill this promise, but only tried to extinguish the critical fuse of his high friends. At the same time, he wrote to other addressees completely different:" In the depths of my soul, I believe that there is great truth in it" (letter to A. Gray, 1867), or: "I would rather die than cease to defend my poor child from attacks" (letter to G. Spencer, 1868). The same notes sounded later : “With regard to pangenesis, I am not going to roll up the banners” (letter to A. Wallace, 1875); “I had to think a lot on this issue, and I am convinced of his great importance, although it will take years until physiologists realize that the genital organs only collect reproductive elements ”(letter to J. Romains, 1875).
Tailless cat can't be obtained by exercising
In most cases, when discussing the hypothesis of Darwin's pangenesis, it is customary to say that its author did not go far from his time, but, they say, Mendel was ahead of his time by 35 years (no wonder his laws were indeed rediscovered 35 years later). But it can be said in another way: in understanding the mechanisms of inheritance of traits, Darwin did not grow up to his contemporary Mendel.
And yet this question was the most important for Darwin. In the first edition of The Origin of Species, he proceeded from the premise that changes in living things occur frequently and that they are indefinite: some bring some benefit to the organism, the rest are harmful or useless. He believed that with regard to useful traits, everything is clear - they are mainly inherited. “Any change, no matter how insignificant it may be, and no matter what reasons it depends on, if it is in any way beneficial for an individual of any species, any such change will contribute to the preservation of the individual and for the most part will be transmitted to offspring,” he wrote. .
He believed that volatility itself does not contain predestination, primordial benefit. At this point he saw a fundamental difference between his views and Lamarck's. There is no "internal striving for perfection", no property of predestination embedded in living beings in "improvement due to slow desire" does not exist (the words "slow desire" belonged to Darwin himself).
However, despite the defiant rejection of the Lamarckian postulate, Darwin, as shown by the above quotation about the inheritance of "any change, no matter how insignificant it may be, and no matter what reasons it may depend on", if only it "was beneficial for the individual of some species," was even at this initial moment not too far from Lamarck. He also attributed to organisms an inherent (i.e., predetermined) ability to preserve any useful deviations in a hereditary basis. The hypothesis of gemmules that perceive useful stimuli did not change the essence of the matter. Darwin did not have a single fact in favor of his hypothesis, and in this sense Lamarck, with his “organ exercise”, was no weaker in argumentation than Darwin.
Rejecting the Lamarckian inheritance of acquired characteristics, Darwin did not offer anything real in return, but simply bypassed the question of what, how and when is inherited, dividing the possible variability into two types. The first is definitely favorable changes that the organism “craves” and which are the result of a direct response to the action of the environment (he denied such inheritance). The second type is indefinite changes that may occur and not under the direct influence of the external environment (they are inherited). In this point, he saw the main difference between his doctrine and the views of Lamarck, which he attributed to erroneous.
But why are the first changes not inherited, while the second ones arise and are inherited? What hereditary structures are in general and how they are transmitted to descendants, he did not imagine. Calling them gemmules, he did not come one iota closer to understanding their nature. Intuitively, he probably guessed that no matter how much you cut off the tails of cats so that they do not knock down Wedgwood figurines when they jump from chests of drawers, the offspring from tailless cats and cats will still have tails.
"Jenkin's Nightmare"
The only belief that Darwin shared with most of his contemporaries was that the transmission of heredity is akin to the fusion of a fluid, say blood. The blood of the record-breaking mother merges with the blood of an ordinary, unremarkable father - and a half-breed is obtained. And if identical organisms (siblings) give offspring, then this offspring will be “pure blood” (they will be called later a pure “line”).
Darwin fully adhered to these views, which is why he was so devastated by the criticism expressed in June 1867 by the engineer Fleming Jenkin in the Northern British Review. Jenkin was the largest specialist in electricity, electric networks, with his personal participation cables were laid in Europe, in South and North America, he is considered the father of the telegraph, he was the closest friend of William Thomson, who later became Lord Kelvin, all his life. A year before the publication of his devastating article on the main principle used by Darwin to justify natural selection, Jenkin became a professor of engineering at University College London. With his brilliantly written paper, without a single superfluous word, Jenkin, it was believed, undermined the Darwinian explanation of the inheritance of useful deviations with one blow.
Suppose Darwin is right, Jenkin explained, and there is an indeterminate variability due to which some single organism has acquired a useful evasion for it (necessarily a single one, otherwise it is a massive Lamarckian change under the influence of the environment). But this lucky one will interbreed with an ordinary individual. This means that there will be a dilution of "bloods" - the trait in the offspring will retain only half of the useful deviation. In the next generation, a quarter will remain from it, then an eighth, etc. As a result, instead of evolution, useful deviations will be absorbed (Jenkin used the term swamping"swamping" or absorption by unchanged hereditary potencies of the altered potency).
Criticism of the professor-engineer aroused feelings in Darwin, which he called only "Jenkin's nightmare." As Darwin admitted in one of his letters, the correctness of the opponent's reasoning "can hardly be doubted." In a letter to Hooker dated August 7, 1860, Darwin wrote: "You know, I felt very humiliated when I finished reading the article."
In the end, after much thought, he saw only one way to respond to criticism: to recognize that the environment directly affects heredity and thereby leads to a change in a large number of individuals living in new conditions at once. Only in this case, the "resorption" of new signs should not have occurred. Such a recognition of the role of the mass direct influence of the environment in progressive evolution meant a decisive rapprochement with the position of Lamarck and the recognition of the principle of inheritance of acquired traits.
Agreeing with the arguments contained in Jenkin's devastating article regarding the Darwinian mechanism of inheritance of useful traits, Darwin decided to correct the next, fifth, and then the sixth edition of the book. “... I am so sad,” he wrote to Hooker, “but my work is leading me to a somewhat greater recognition of the direct influence of physical conditions. Perhaps I regret it because it lessens the glory of natural selection.”
Meanwhile, a saving way for Darwin already existed. Gregor Mendel had proved a few years earlier that hereditary structures do not merge with anything, but keep their structure unchanged. If the unit responsible for the transmission of heredity (later called the gene) is changed, and as a result the trait controlled by it is formed in a new way, then all the descendants of this first hereditarily changed organism will carry the same new trait. The "Jenkin Nightmare" that had spoiled so much of Darwin's blood was completely dissipated, and evolutionary theory took on a complete form. But Darwin did not know the work of Mendel, and he himself did not think of his conclusions.
Literature:
1) Loren C. Eisley. Charles Darwin, Edward Blyth, and the theory of natural selection // Proc. amer. Philosopher. soc. 1959. V. 03, N. 1. P. 94–115.
2) Edward Blyth. An attempt to classify the "varieties" of animals, with observations on the marked seasonal and other changes which naturally take place in various British species, and which do not constitute varieties // (London). 1835. V. 8. P. 40–53; On the physiological distinction between man and all other animals, etc. // The Magazine of Natural History(London), n.s. 1837. V. 1. P. 1–9, and P. 77–85, and P. 131–141; excerpts from Blyth's work, as well as memoirs of him by Arthur Grout, published in the August issue of the magazine Journ. Asiatic Society of Bengal, 1875, are given as an appendix to Eisley's article (see note / 1 /, pp. 115–160).
3) Wallace A. R. Darwinism. Presentation of the theory of natural selection and some of its applications. Translation from English. prof. M. A. Menzbira. Library for self-education. M.: Ed. Sytin, 1898. T. XV.
4) Fleeming Jenkin. Review of The Origin of Species // North British Review. 1867. V. 46. P. 277–318.
See Science First Hand, 2010, No. 3 (33). pp. 88–103.
"Science first hand", 2005, No. 3 (6). pp. 106–119.
Born Wedgwood, daughter of the owner of a famous pottery factory (called "Wedgewoods" to this day). She was famous for many virtues, including being a good pianist and taking music lessons from Chopin himself.
The most prominent American Darwinists of the 20th century. E. Mayr, S. Darlington, S. D. Gould later disputed the opinion regarding Darwin's borrowing of the ideas of E. Blyth, based on the fact that Blyth argued about the selection of degraded forms, and not about progressive evolution.
Already in the XX century. Wallace's "law" on the role of geographical isolation in accelerating the evolution of species has become an integral part of the doctrine called the "Synthetic Theory of Evolution", developed by the American scientist of Russian origin F. G. Dobzhansky. The role of geographic isolation for gene selection was first pointed out in 1926 by S. S. Chetverikov in his work “On Some Moments evolutionary process from the point of view of modern genetics.
Charles Darwin (1809 - 1882) formulated the theory of evolution as a result of natural selection.
Background of evolutionary theory
Socio-economic (intensive development of industry, rapid urban growth, a significant rise in agriculture, the intensification of breeding work to develop new varieties of plants and animal breeds in England).
Scientific: In the field of biology - progress in the taxonomy of animals and plants, biogeography, paleontology, comparative anatomy, embryology, etc.
Scientific in other fields: astronomy, which developed theories of origin solar system; geology, which discovered the successive formation of sedimentary rocks; chemistry, which established similarities in the composition of animate and inanimate nature, etc.
1859 "The Origin of Species by Means of Natural Selection, or the Preservation of Chosen Breeds in the Struggle for Life."
The logical structure of Darwinism
Heredity. Variability. The intensity of reproduction (geometric progression). Limited space and resources for life.
Obvious properties of organisms
Struggle for existence
Natural selection
The theory of the origin of species created by Darwin is based on the following fundamentally important provisions:
A phylogenetic change in a species is always caused by a change in environmental conditions.
The formation of a new species begins with the formation of new intraspecific forms, which Darwin called varieties.
As a result of natural selection, new organic forms adapt to changing conditions.
The formation of species is a long historical process.
The main direction of phylogenesis is divergence. But the possibility of the formation of convergent forms is not excluded.
Each large group of animals or plants always comes from the same root (monophyletic origin).
The main provisions of the theory of Darwin and Wallace
All organisms are characterized by variability.
The number of offspring born into the world is much greater (reproduction intensity) than the number that can find food (limited resources and places to live). Therefore, most of the offspring die.
Since more individuals are born than can survive, there is a struggle for existence (explicit or indirect).
Hereditary changes that make it easier for an organism to survive in certain specific conditions give them an advantage over others, that is, the fittest survive (natural selection).
The surviving individuals give rise to the next generations, and thus, successful changes are fixed. As a result, distant descendants may differ significantly from their ancestors.
Essence The theory of evolution is as follows: a huge variety of species on Earth, adapted to certain conditions of existence, were formed due to constantly arising in nature multidirectional hereditary changes and natural selection. The ability of organisms to intensive reproduction and the simultaneous survival of a few individuals, the most adapted to specific environmental conditions, is a consequence of the struggle for existence. Thus, between species there is a struggle for existence, as a result of which organisms that are most adapted to specific environmental conditions survive. Meaning Darwin's theory consists in establishing the main driving forces for the evolution of the organic world and introducing the natural-historical method into biology.
The creation by man of new varieties of plants or animal breeds is based on three factors - variability, heredity and selection.
Heredity is the property of living organisms to preserve and transmit to offspring the features of their structure and development with the help of genes. Due to heredity from generation to generation, the characteristics of a species, variety, breed, strain are preserved. Communication between generations is carried out during reproduction through haploid or diploid cells. The leading role in heredity belongs to chromosomes capable of self-duplication and formation with the help of genes of the entire complex of traits characteristic of the species. The entire set of genes characteristic of an individual of a species makes up the genotype.
