The origin of the species

the Origin of the species (One the origin off species by means off natural selection, gold the safeguarding off favoured races in the struggle for life) is a work of Charles Darwin, published the November 29th 1859 and in which he explains the mechanism governing the evolution of the species in nature. The many examples which illustrate the work result from its study trips, in particular that which it did on the Beagle December 27th 1831 with the October 2nd 1836 and which passed by the islands Galapagos. Darwin took along with him, on this occasion, the Principes of geology of Charles Lyell treating fossils and of their evolution.

This work is regarded today as founder of the theory of the evolution. Very honestly, Darwin does not pay there less homage to his predecessors in the search of the truth, as Newton had done it in its Principia .

Genesis of work

Former work cities by Darwin

Transformation of the species

Aristote, in its Physicoe Auscultationes : " worked characteristics in a way adapted by an internal spontaneousness were preserved, while in the contrary case they perished and perish encore".
Buffon, " the first (...) which covered this subject in way (...) scientifique"
Lamarck ( zoological Philosophy , 1809), " the first which woke up by its conclusions a serious attention on this sujet"
Goethe, Erasme Darwin (his grandfather) and Isidore Geoffroy Saint-Hilaire, all in 1794-95

Durable modifications by human intervention

Botanical, 1822, W. Hebert, senior of Manchester
Zoology, as from 1826: many work on

results obtained by the stockbreeders
the " creative power désordonnée" of variation of the descents, from which those do not have any more but to draw.

The synthesis darwinienne

According to the thesis of Stephen Jay Gould, it seems that he was not in the intentions of Darwin to publish his work, that he kept private during twenty years. It is only when Alfred Russel Wallace presents to them his to him which lead to the same conclusions that it decides to publish to keep the paternity of the theory.

The evolution directed of the species was already at its time a fact largely admitted and put into practice by the stockbreeders by means of crossings. It did not lend to dispute, and was not named besides thus. One spoke simply then about “improvement of the race”, in general bovine or ovine. The choice of the best animals for the reproduction was undoubtedly practiced since the Antiquité accordingly: who would have bought at full price a bull malingre for the reproduction? Who wouldn't have observed that the children rather post some of the features of their parents than those of the neighbors (in theory)?

The contribution of Darwin is elsewhere:

In the absence of stockbreeders, the species evolve/move all the same (from where the name of natural evolution ).
This evolution results from two convergent factors: variation, then selection.
the Natural selection results in its turn from two factors:

selection of survival: those which die before the age of the reproduction do not have a descent;
sexual Selection: those which do not manage to convince one or a partner do not have a descent either, or will have some less than the others. He thus explains phenomena like the tail of the peacock , which seems to make this one more vulnerable to predatory and could seem contradicting the theory of the survival of most suited.

The mechanism

There is a selection why? Because the number of possible children per couple is higher than two: the population increases as a long time as resources are available, and once they are saturated, then all the individuals cannot survive at the same time. This point is shown of Thomas Malthus, which had seems it be the first to state it.

Darwin is not posed in his book into dogmatic. Each one of its thought processes there is explained and supported examples. Errors that one finds there (heredity of the raising of the dogs pointers!) are minor compared to the contribution of the remainder, and comprehensible being a theory have just been born.

More precisely, Darwin shows that his theory is compatible with a possible transmission of acquired features, even if it does not have, to paraphrase Laplace need for this assumption . There its true opposition with Lamarck is: in the theory of this last, indeed, this transmission was essential under penalty of collapse of the theory.

Insufficiencies?

Darwin admits in his book that certain functions, in particular those of the eye, remain not easily explainable within the framework of its theory (they are it less today, affirms Richard Dawkins, by supporting this idea of small simulations of principle on computer). But if he admits that his theory can be incomplete , the examples which he gives not making it possible to suppose it distorts .

The reception

The book leaves in bookstore the November 24th 1859, the 1.250 specimens of the first pulling are exhausted in the course of the day. It will be republished six times between 1859 and 1872. The idea will be adopted immediately by Ernest Renan. Victor Hugo, on the other hand, will remain opposite there all its life.

Anecdotes

the report of 1859 of the British royal Académie establishing its annual statement of account of the advance of sciences will not mention of it less “one year scientific a little disappointing, where nothing very important was discovered”!
the year 1863 sees a confirmation of the theory when the naturalist Henry Walter Bates publishes a paper on the theory of the Mimétisme, The imitation by has species off other life forms gold inanimate objects , where it shows that a species of Amazonian butterfly evolved/moved to avoid colors similar to another close species neglected by the predatory birds.

A small error

Darwin written at one time this:

" the act to fall in stop is probably only one exaggeration of the short pause which the animal makes which collects to spring on its prey. The first tendency to stop once expressed, the methodical selection, united with the hereditary effects of a severe raising in each successive generation, quickly had to supplement work "

We know today that no raising, so severe was it, cannot have hereditary effects (on the other hand, guenons with which one teaches the sign language teaches it in their turn with their small, but that is not any more about the genetics). See on this subject the articles Vernalization and Lyssenko

Darwin was not informed of work of Mendel, which at the same time endeavoured to quantify the heredity of the characters. The junction of this work will be done only then.

External bonds

the Origin of the species, French text.

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