Chapters in the history of the theory of evolution about the ideas and those who conceived them - Chapter 13 - Part D

Here is the fourth and last part of chapter 13 - entitled The war of existence of the theory of evolution in David Wall's book

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Fleming Jenkin

Henry Charles Fleeming Jenkin (Henry Charles Fleeming Jenkin, 1833–1885) was a Scottish engineer, who was employed for about ten years in designing submarine communication cables. Later he was a professor of engineering at the universities of London and Edinburgh. More details about the man and his work can be found in the Hebrew translation of Steven J. Gold's article "Fleming Jenkin Shev Alino".¹

Jenkin wrote in 1867 a review article on the "Origin of Species". Jenkin had objections to almost all of Darwin's assumptions, including the supposedly unlimited time that allows for any eventuality to occur:

If six years or sixty years were enough to cultivate a species of pigeon that differs from the rock pigeon, say, in the shape of the tail, is it permissible to assume that six million or six billion years later the pigeon will turn into something similar to the thrush? It is no more accurate than to assume that if a cannon ball travels one mile per minute, then in an hour it will travel sixty miles, and in the course of generations it will reach the stars.²

In particular, Jenkin attacked Darwin's assumption of unlimited variation in nature. Jenkin described each species as a datum within a spherical space, symbolizing the range of possible variation. Each detail is a point within this space. The center of the ball is the average for that species. There are details that are close to the envelope of space, others close to the center. Variation occurs in all directions, but most changes are toward the center. To create a new species you have to go beyond the range of variation within the species. It is usually impossible to exceed the envelope of space, except in exceptional and accidental cases. Natural selection, operating within the shell, cannot bring about the creation of a new species.

In the first editions of the "Origin of Species" Darwin wrote that such unusual details (sports) are the beginning of new species. Jenkin attacked this assumption. Based on the generally accepted explanation at the time, that the traits of the father and mother are blended in the offspring (blending inheritance), Jenkin claimed that even if an individual appeared that was much more successful than the others - his advantage would decrease by half in each generation and would not be preserved in his offspring, and therefore could not be the beginning of a new species.

Jenkin used an example that reflects the prejudices that prevailed in the nineteenth century about the supremacy of the white race. Suppose that one white person survived a shipwreck near an island inhabited entirely by blacks ("negroes") and that the survivor befriended the locals. Let's also assume that the white survivor had extraordinary physical and intellectual skills, which gave him a huge advantage over the other residents in the war of existence and he survived the clashes in which he killed other residents. It is possible that this man would have been crowned the king of the island, and could have acquired many wives for him and raised masses of offspring. In the first generation he may have produced a few dozen intelligent mulattoes, and one of these may become king in place of his father - but the white race will not take over the island, as long as the advantaged breed freely with the inferior inhabitants.

Indeed, if that individual with the advantage could give his special qualities to all his descendants for generations without the advantage being known - because then his descendants could really replace the original species, as Darwin predicted. But how does such a case differ from the assertion that from time to time a new species is created by a higher power?³ Darwin had no answer to this argument, and he was forced to change a paragraph in the fifth edition of his book - to abandon the idea that sports could be the progenitors of new species, and to concentrate on the action of natural selection on individual variation.

Jenkin also rejected Darwin's assumption that any similarity between species is evidence of close descent. Jenkin explained that animals and plants are composed of a non-infinite number of elementary components, just as complicated chemical compounds are composed of a finite number of elements. A chemical compound is analogous to the hybrids in nature. The problem of sorting in the systematics of the animal world is similar to the problems encountered by the chemist sorting compounds: the more compounds there are to sort, the more difficult it is to differentiate between them. But this also increases the probability that a similarity will be found between them. According to the common components, it is necessary that there be groups of animals whose composition is more similar to each other than to the composition of other groups.⁴

Jenkin's general conclusion is that Darwin's theory is based on assumptions rather than facts. It is possible that there was variation between animals, and it is possible that this variation accumulated over time. Variants may have become stable. It is possible that new continents were discovered above the sea, or continents sank and disappeared in whole or in part, thereby helping or limiting the distribution of animals, and so on. All these and similar things may have happened in reality. Therefore it is possible that Darwin's theory is correct. But there is only very little evidence that these possibilities did materialize, and therefore: "Darwin's theory is nothing but speculation - [although] intelligent and plausible, but surely the times have passed when hypotheses of this type, which are not supported by facts, are considered possible only because in our ignorance we cannot To find sufficient reasons to decide that they are not correct - although we cannot prove their correctness".⁵

Does the fame go to Darwin rightly?

In the twentieth century, claims were heard from time to time that Darwin gained fame unfairly. The journalist Barkman, based on a review of letters and notes from the nineteenth century, accused Darwin and his friends in his book of a plot they concocted to deny Wallace the birthright, through a legal exercise.⁶ From time to time the names of people who expressed ideas about natural selection are brought up and Darwin did not know about them, or mentioned their names briefly in the introduction to the sixth and last edition of "The Origin of Species" (for example Patrick Matteau).

An interesting example was put forward by the historian Lauren Eisley. Eisley researched and found two articles published before "The Origin of Species" in a newspaper to which Darwin was a subscriber. The articles (from the years 1835, 1837) include ideas that can be understood as similar to the idea of ​​natural selection. As a fair historian, Eisley included the full text of both articles in his book. The author of the articles was Edward Blyth (1810-1873, Blyth), a biologist and passionate nature lover. Blythe was a partner in the translation of Kivia's book into English (1840) and participated in scientific expeditions to India and China. He lived for many years in Calcutta, India, where he ran the Nature Museum.⁷ Darwin knew Blyth well and used his knowledge in writing his books on mate selection and domestication of plants and animals. Nevertheless, Darwin in "The Origin of Species" did not mention Blyth's articles, although he cited the man in other contexts. Eisley claims that Darwin must have read both papers, and suggests that he deliberately avoided quoting them in order to maintain his primacy over the idea of ​​natural selection.

In the most important of the two articles Dan Blythe⁸ On the question of the difference between breed and species - a question that also occupied Darwin, and describes a process of selection in the sense of eliminating weak types and the survival of the stronger individuals, who will pass on these traits to their descendants: since the stronger will always prevail over the weaker, the latter will have fewer opportunities to continue the race, and the more organized He will always obtain a greater amount of resources, and thus, by eliminating his opponents, he will be able to pass on his superior qualities to a greater number of offspring.
However, from reading the text it becomes clear that Blyth understood the increased mortality of the weak as a filtering device by the supreme providence and not as a natural process. On the basis of his observations of the changes in the fur colors of mammals with the seasons, Blythe wrote explicitly: "These changes are an expression of the planning of a higher power - to adapt the animals to the climatic conditions and for crazy camouflage and protection".⁹

Darwin, in stark contrast to Blythe, stated that nature runs without the intervention of a higher power. Darwin cannot be accused of ignoring Blyth's articles.

To Mark and Darwin - the common and the different

In retrospect, Darwin's theory of evolution was accepted by most biologists, while Lamarck's ideas were denounced as incorrect, unscientific or ridiculous. But in the middle of the nineteenth century there were many who had difficulty distinguishing between the two theories, and mentioned them in the same breath as "the theory of Lamarck and Darwin" or "the theory of Lamarck with Darwin's modifications". Even Lyle often mentioned the two teachings together in his letters.¹⁰

Darwin, like Mark fifty years before him, believed that there are connections of origin between all species. The possibility of transmutation is common to both theories: life was created in its simplest form, changed over time and developed into more complex forms. The similarity between the two theories also stems from the fact that Darwin, like Lamarck, took into account the inheritance of acquired traits through "use and non-use". The inheritance of acquired traits - the subject that provoked the most opposition to Lamarck in the twentieth century - was not a central issue of controversy until the end of the nineteenth century, and Darwin used this explanation in many places in his book "The Origin of Species" and also in his later book on "The Descent of Man". This similarity made it difficult for readers to distinguish between them. In a letter from 1844, Darwin described his attitude to Lamarck's ideas: "God forbid Lamarck's nonsense about 'tendency to progress', 'slow adaptation due to the will of animals', etc. But the conclusions I reach are not much different from his, although the means that cause changes are quite different."¹¹

Darwin vehemently denied that he had been helped by Lamarck's ideas, and the repeated reference to their similarity angered him. He wrote to Lyle:

You often allude to Lamarck's work. I don't know what you think of him, but to me [Lamarck's book] seems very bad. I did not draw any facts or ideas from him.¹²

Plato, Buffon, my grandfather [Erasmus Darwin] before Marx, and others, all expressed the self-evident idea that if species were not created individually, they would have to evolve from other species, and I can find no other similarity between the "origin of species" and Marx. I believe that presenting things in this way is detrimental to its reception [of "The Origin of Species"], and connects Wallace's and my ideas with what I think, after reading and re-reading it carefully, a bad book which - to my well-remembered surprise - did nothing for me.¹³

Footnotes:

1. Gold b1994.
2. Jenkin 1867, p. 2
3. Ibid., pp. 4–5.
4. Ibid., P. 11.
5. Ibid., P. 14.
6. Brackman 1980
7. Eisley 1981, p. 169
8. Blyth 1835, in Eisley 1981
9. Eisley 1981, p. 103
10. Lyell 1881, II: 332
11. Darwin, F. 1887, II: 23
12. Ibid., II: 215.
13. Ibid., II: 198.