Charles Darwin at Six (Ellen Sharples Oil, 1816) ; Darwin at 28, shortly after his return from the voyage aboard the Beagle (George Richmond Watercolor, 1836-7); Darwin at the age of 33 with his son William (daguerreotype reproduced in Karl Pearson's book In The Life, Letters, and Labors of Francis Galton); Darwin at 65 (photograph and art-of-visit published by John G. Murdoch, digitally colored); and profile of Darwin's marble bust exhibited at the National History Museum in London, in position with the spine of the first edition of Origin of Species.
Darwin's impact on science and paleontology needs no further presentation, but it is worth noting the impact Humboldt's work on Darwin: "Nothing has ever so aroused my enthusiasm as reading Humboldt's Personal Narrative,, Darwin wrote. He stated that he would not have embarked on the Beagle or written The Origin of Species without that influence.
Comics showing the arrival of the HMS Beagle in the River Plate region and Darwin's meeting of Quaternary megafauna fossils Argentina, Extracted from the comic strip produced by the company Exodus Travel in celebration of Darwin Day.
As a fossil collector, Darwin gathered around his world a formidable collection of 1,529 vertebrate specimens, mollusks, brachiopods, barnacles and fossil plants, about one third of which are described as new species and named by different experts. The enthusiasm and importance that he reserved for fossils can be illustrated by this excerpt from a letter sent from the Falkland Islands to Sister Catherine Darwin on April 6, 1834, in which he relativized his passion for youth, hunting: "There is nothing like it." Geology, the pleasure of the early days of partridge hunting cannot be compared to the pleasure of finding a good group of fossil bones, which tell the story of bygone days almost as if they spoke. " Further correspondence and notes show us that by the time Darwin arrived in the Galapagos Islands, his ideas about the evolution of species through natural selection were well advanced and that his most fruitful inspiration came from the quaternary megafauna fossils he himself found in Argentina, influenced by Lund's discoveries in Minas Gerais as reported in chapter X (Of Geological Succession of Living Beings) in The Origin of Species: "(...) This kinship becomes even more evident from the admirable collection of fossil bones collected in the caves of Brazil by Mr. Lund and Mr. Claussen, these facts impressed me so vividly that from 1839 to 1845 he strongly insisted on this 'law of succession of types' and 'these'. remarkable kinship relations between extinct forms and living forms on the same continent. '(...) there are in the caves of Brazil a large number of fossil species their configuration and by all other characters approximate the species that currently live in South America, and some may have been the actual ancestors of the living species. "
Darwin, like everyone else in his day, applied the Cuvierian laws and principles of comparative anatomy (correlation between parts and subordination of characters), since they allowed the reconstruction of extinct organisms from fragmented fossils. But gradually these principles were re-signified in Darwin's new paradigm, linking the fundamental agreement of structure, or type unit, not to a geometric rule, but to what he termed "unity of descent" . In other words, the common ancestry. The data were the same, but in order to reach this new cognitive objective, it was necessary to understand the phylogenetic relationships between species, which was absent from the model cuvieriano. Anticipating modern species concepts in the light of phylogenetic systematics, Darwin tells us about the then rarity of intermediate forms between two species, a theme that is a true obsession with critics of the day, and of today's uninformed: intermediaries that exist between each of them and an unknown ancestor, common to both, which in turn must be different from their modified descendants "(Chapter X, From Geological Succession of Living Beings, from The Origin of Species). With that expression, Darwin anticipated the study of sibling groups as a key to the proper positioning of extinct forms in evolutionary narrative, rather than the attempt to establish a direct ancestor-descendant relationship. Surely Darwin would be jubilant with the modern perspective brought by Phylogenetic Systematics and the multitude of examples of intermediate morphotypes that the fossil record has given us since its time, and which position themselves in the history of life exactly as predicted by him. Still reminding uninformed critics that the attributes of primitive, intermediate, and derived are inherent in characters, not in the species themselves.
Darwin also overcomes, and opposes, the Lamarckian perspective that if an unbroken offspring between an ancestral species and a living species can be detected, then there would have been no extinction, and all fossils would necessarily be ancestors of the living form to them. , without loss or gain in diversity over time2. The very detail of stratigraphy and paleontology has made the Lamarckian view unsustainable, and Darwin recognizes extinctions outside the catastrophic mold as a consequence of the natural selection mechanism in economics of nature and a counterpart to species diversification derived from natural selection over common ancestors.
Cuvier's establishment of extinction was used by Darwin as a fundamental component of his own concept of natural selection, but incorporated into it. as a biological phenomenon. In Cuvier, by contrast, extinction is treated as a catastrophic contingency of the environment on populations. Adhering to the uniformitarian paradigm that followed Catastrophism, Darwin did not deny the occurrence of any cataclysms, but certainly did not exalt them as Cuvier did not acknowledge that sudden extinctions might occur. Nor did it attribute to the changes of the physical environment either propulsion for adaptation or extinction, highlighting in the competition between individuals and species the source of the instability that leads to change. The irreconcilable propositions of extinction and transformism between Cuvier and Lamarck, not imbedded in Darwin as both consequences of the same processes.
Darwin, who recognized Cuvier (and Linnaeus) as his "gods" in a letter sent to his friend William Ogle just a month and a half before he passed away, set a new paradigm, now materialistic and evolutionary, for understanding extinctions and at the same time. replacement of the cuvierian fixist, determinist and essentialist paradigm. Posterity recognized the reality of several "globe revolutions" and accommodated the Darwinian revolution in Cuvierian paleontology.
1 Faria FFA. 2012. A revolução darwiniana na paleontologia e a ideia de progresso no processo evolutivo. Scientiae Studia, 10 (2): 297-326.
2 Ferreira MA. Transformismo e extinção: de Lamarck a Darwin. Tese, Programa de Pós-graduação em Filosofia, Universidade de São Paulo. 155p.
