In response to Isaac de la Peyrere‘s theory of polygenesis, Hale, Chief Justice of the King’s Bench, advanced his own theory that the earth was not eternal, but rather had a spontaneous “beginning,” and defended “the Mosaic account of the single origin of all peoples.“ Hale also seems to have been the first to use the expression ‘Geometrical Proportion’ for the growth of a population from a single family” (Hutchinson). In this he anticipated Malthus (No. 215.4). He believed that in animals, especially insects, various natural calamities reduce the numbers to low levels intermittently, so maintaining a balance of nature. Digital facsimile from the Hathi Trust at this link.

The earliest work of importance in comparative morphology. Tyson compared the anatomy of man and monkeys and between the two he placed the chimpanzee, which he regarded as the typical pygmy. This was the origin of the idea of a “missing link” in the ascent of man from the apes. Facsimile reprint with introduction, 1966. Biography of Tyson by Ashley Montagu, Philadelphia, 1943.

This pioneering work on experimental entomology incorporates Bonnet’s most important discovery–parthenogenetic reproduction–based on his study of aphids. Bonnet used the result of this and other discoveries as a basis for speculation about life on earth. This work presents in tabular form his version of the “great chain of being”. Bonnet’s concept of the essential continuity of life, a consequence of his discovery and preformationist interpretation of parthenogenesis, was a major force in the shaping of later evolutionary opinion. See No. 472.

This vast work is divided into seven parts. I: Histoire naturelle générale et particulière…15 vols., by Buffon and L.J.M. Daubenton (1749-67). II: Histoire naturelle des oiseaux. 9 vols., by Buffon, P. Guéneau de Montbeillard and G.L.C.A. Bexon (1770-1783). III: Histoire naturelle des mineraux. 5 vols., by Buffon (1783-88). IV: Supplement. 7 vols., by Buffon, the last volume finished by La Cépède after Buffon’s death (1774-1789). V: Histoire naturelle des quadrupèdes ovipare et des serpents. 2 vols., by Le Compte de la Cépède (1788-89). VI: Histoire naturelle des poissons. 5 vols., by La Cépède (1798- “An XI” [1802/03]). Histoire naturelle des cétacées. 1 vol., by La Cépède. (An XII [1803/04]).

“Natural history, prior to Buffon, had all the earmarks of an avocation, a hobby. Buffon is the one who raised it to the status of a science” (Mayr). Buffon is also regarded as an important early contributor to the history of evolutionary thought as he introduced a large number of evolutionary problems, such as common descent, extinction, and reproductive isolation of species, into the realm of scientific investigation.

Herder’s history has long been regarded as a very strong statement of Darwinian evolution before Darwin: many single passages come close to the evolution theory. Among the passages most often regarded as anticipating Darwin are those on the temporal sequence of forms from simpler to more highly organized, and on the overabundance of nature with the ensuing struggle for existence between species and individuals.

The first edition of part 2, preceded part 1, being published in 1789. This poem was the chief source of Erasmus Darwin's literary fame during his lifetime. Like his other works, this poem contains a great deal of frequently advanced scientific information in the nearly 300 footnotes and 115 pages of appendices. This work also contains five plates engraved by William Blake, including "The fertilisation of Egypt" after a design by Henry Fuseli, and 4 engravings of the Portland Vase.

Sprengel demonstrated for the first time that the whole structure of nectar-bearing flowers is adapted for fertilization by insects. In his study of the Rose-bay Sprengel discovered dichogamy – that in some plants the two sexes (stigmas and anthers) while occurring in one blossom, mature at different times. This prevents the flowers from being fertilized by their own pollen, and necessitates fertilization by the pollen carried to them by insects.

Grandfather of Charles Darwin and Francis Galton, Erasmus Darwin provided in Zoonomia, his major work in medicine and natural science, the first consistent all-embracing hypothesis of evolution. Nevertheless, his grandson, Charles, said Erasmus’s theory had no effect on his On the Origin of Species.

Malthus laid down the principle that populations increase in geometrical ratio, but that subsistence increases only in arithmetical ratio. He argued that a stage is reached where increase of populations must be limited by sheer want, and he advocated checks on population increase in order to reduce misery and want. His work was an important influence on both Darwin and Wallace in their formulation of the concept of natural selection. It also had a profound influence on the decrease in size of families down to the present time. The book was at first published anonymously, but Malthus attached his name to the greatly expanded second edition of 1803. Malthus continued to revise the work through the sixth edition, 2 vols., 1826. All editions but the fourth contain significant new material.

The “Discours d’ouverture” contains Lamarck’s first published statement of the theory of the inheritance of acquired characteristics. See No. 316.

Simultaneously with Lamarck, Treviranus coined the term “biology” for the study of living things, and he was the first to use it in a book title. This massive work was a summary of all basic knowledge about the structure and function of living matter. Treviranus wrote that any living creature has the ability to adapt its organization to changing external conditions. Thus both Haeckel and Weismann considered Treviranus to be a precurser of evolution theory, even though Treviranus never explained how changes in organic structures occurred nor how they could become hereditary. Digital facsimile from Biodiversity Heritage Library at this link.

Erasmus Darwin's last poem, which mainly expounds his theories of evolution. He traces the progress of life form its origin as microscopic specks in premeval seas to its culmination in a civilized human society. The first canto shows life's origin and its evolution from aquatic to land forms. The second deals with reproduction--asexual, hermaphroditic and finally sexual reproduction with all its advantages. The third canto traces the progress of the mind, from its origin as a mere meeting-place of nerves to its present complexity in man. In the fourth canto Darwin descrbies the struggle for existence and the survival of the fittest. The essay-length scientific notes (last 124pp.) contain summaries of theories of spontaneous generation, etc. Erasmus Darwin's theory of evolution has been compared to Lamarckism.

Digital facsimile from the Internet Archive at this link.

Lamarck was one of the greatest of the comparative anatomists. This work is considered the greatest exposition of his argument that evolution occurred by the inheritance of characteristics acquired by animals as a result of the use or disuse of organs in response to external stimuli. English translation by H. Elliot, 1914. Digital facsimile of the 1809 edition from Google Books at this link.

Prichard, a Bristol physician, classified and systematized facts relating to the races of men better than any previous writer. His interest in anthropology was stimulated by one of the pressing questions of his day: Did all the races of mankind have a common origin, as stated in the Scriptures, or did they spring from different ancestral stocks? Prichard, a confirmed monogenist, sought to demonstrate the common origin of the human races by compiling evidence from a variety of fields, including anatomy, physiology, comparative psychology, linguistics and cross-cultural studies. He theorized that the earliest races of mankind had been dark-skinned, and that the black races, far from representing a degeneration from white "perfection," were the origin from which the white races had sprung.

The second edition of his book, 1826, contains a remarkable anticipation of modern views on evolution, views which were suppressed in later editions. Facsimile edited with an introductory essay [and bibliography] by G. W. Stocking, Jr., Chicago, University Press, 1973. The one-volume first edition was unillustrated. By the 3rd edition the work was expanded to 5 vols. (1836-47) and contained many color plates. In that form it synthesized all then known information about the various races of mankind, forming a basis for modern ethnological research.

Prichard issued a popularization of his work, with numerous color plates, as The natural history of man (1843). The fourth edition of that was edited and enlarged, and published in 2 vols. by Edwin Norris (1855). 

An elaborate expansion of Lamarck’s one-volume work with the same title published in Paris, 1801 (No.215.5). As a systematist Lamarck made important contributions to biology. He separated spiders and crustaceans from insects, made advances in the classification of worms and echinoderms, and introduced the classification of animals into vertebrates and invertebrates. The introduction to this work includes Lamarck’s summary of his four laws of evolution. Digital facsimile from the Biodiversity Heritage Library, Internet Archive, at this link.

First statement of the theory of natural selection. Wells’s paper on a white woman with patchy brown discoloration of the skin contains an almost complete anticipation of Darwin’s theory of natural selection, although it was completely ignored until it was resurrected by a correspondent of Darwin in the 1860s. The volume also contains Wells’s autobiography. See no. 1604.

This work set forth Lawrence's then radical and remarkably advanced ideas concerning evolution and heredity. Arguing that theology and metaphysics had no place in science, Lawrence relied instead on empirical evidence in his examination of variation in animals and man, and the dissemination of variation through inheritance. On the question of cause, Lawrence disagreed with those who ascribed variation to external factors such as climate, and rejected the Lamarckian notion of the inheritance of acquired characteristics. His understanding of the mechanics of heredity was well ahead of his time: he stated that "offspring inherit only [their parents'] connate qualities and not any of the acquired qualities," and that the "signal diversities which constitute differences of race in animals . . . can only be explained by two principles . . . namely, the occasional production of an offspring with different characters from those of the parents, as a native or congenital variety; and the propagation of such varieties by generation" (p. 510). While Lawrence did not grasp the role that natural selection plays in the origination of new species, he recognized that "selections and exclusions," including geographical separation, were the means of change and adaptation in all animals, including humans. He noted that men as well as animals can be improved by selective breeding, and pointed out that sexual selection was responsible for enhancing the beauty of the aristocracy:

"The great and noble have generally had it more in their power than others to select the beauty of nations in marriage; and thus . . . they have distinguished their order, as much by elegant proportions of person, as by its prerogatives in society" (p. 454) Lawrence investigated the human races in detail, and insisted that the proper approach to this study was a zoological one, since the question of variation in mankind "cannot be settled from the Jewish Scriptures; nor from other historical records" (p. 243). The Natural History of Man came under fire from conservatives and clergy for its materialist approach to human life, and Lawrence was accused of atheism for having dared to challenge the relevance of Scripture to science. In 1822 the Court of Chancery ruled the Natural History blasphemous, thus revoking the work's copyright. Lawrence was forced to withdraw the book; however, it continued to be republished in unauthorized editiions. Darwin , who owned one of the unauthorized editions, cited Lawrence's book five times in The Descent of Man (1871)

"Combe argues that the human mind is best understood through Phrenology, and that the relative size of the various regions of the brain defined by Phrenology determines a persons behavior and potential interactions with the external world. In The Constitution of Man Combe uses Phrenology to create a practical science of morality,^[2] proposing that conforming to Natural Laws leads to happiness based on the Phrenological understanding of human nature.^[3] The book was an international bestseller, selling at least 100,000 copies in Britain alone^[4] and over 300,000 copies worldwide by 1855, largely due to the publication of the 'people's edition,'^[5] making it one of the best-sellers of the nineteenth century " (Wikipedia article on The Constitution of Man, accessed 03-2018).

"In this book, Combe wrote: "Mental qualities are determined by the size, form and constitution of the brain; and these are transmitted by hereditary descent". ‘Combe was part of an active Edinburgh scene composed of people thinking about the nature of heredity and its possible malleability, such as Lamarck proposed. Combe himself was not a Lamarckian, but in the decades before the publication of Darwin's Origin of Species, the Constitution was probably the single most important vehicle for the dissemination of naturalistic progressivism in the English-speaking world’^[13] "(Wikipedia article on George Combe, accessed 03-2018).

Digital facsimile from Google Books at this link.

Goethe believed that in 1784 he demonstrated the presence of the intermaxillary (premaxillary) bone in man, proving an anatomical connection between man and the lower animals, and certifying to Goethe that there is no fundamental difference between man and apes. He was one of the pioneers of evolution and the first to use the term “morphology”. Digital facsimile from the Internet Archive at this link. See George A. Wells, "Goethe and the intermaxillary bone," British Journal for the History of Science, 3 (1967) 348-61. (Available from JSTOR at this link.)

The “first clear and complete” anticipation of the Darwinian theory of evolution by natural selection. The appendix to Matthew’s work actually uses the expression, “natural process of selection”. See W.J. Dempster, Patrick Matthew and natural selection: A nineteenth century gentleman-farmer, naturalist and writer, Edinburgh, Paul Harris, 1983.

Darwin's teacher, John Stevens Henslow, had some of Darwin's letters to him published for private distribution as a pamphlet while Darwin was on the Beagle circumnavigation. Estimates of the number of copies printed vary from about 25 to about 200.

Darwin’s first published book, now universally known as The Voyage of the Beagle, is the most often read and the most often printed of all his works, after On the origin of species. Its relation to the background of Darwin's evolutionary ideas has often been stressed.

The traditionally identified first issue forms the third volume of The Narrative of the Voyages of H. M. Ships Adventure and Beagle, edited by Captain Robert Fitzroy and published, in three volumes and an appendix to Volume II, in 1839 in London by Henry Colburn. In its first separate issue, also in 1839, it was called Journal of Researches into the Geology and Natural History. Whether the separate version was issued simultaneously with the set, or slightly later is unknown, as both were advertised in the same set of advertisements in August 1839. The text and maps of the separate version are identifical to the set except that pp. i-iv of the preliminaries are cancels and [v-vi], the original volume title, is discarded.

Though Darwin tended to discard or disperse the manuscripts of his later works after they were published, in some cases giving sheets to his children for use as scrap paper, he saved the  original autograph manuscript for this work, and it is preserved at Down House. The manuscript was reproduced in facsimile by Genesis Publications, London, 1979.

Part 1: Fossil mammalia by Richard Owen; Part 2: Mammalia by George Waterhouse; Part 3: Birds by John Gould; Part 4: Fish by Leonard Jenyns; Part 5: Reptiles by Thomas Bell. Digital facsimile from the Internet Archive at this link.

With slight modification, Darwin's work remains the accepted explanation for these phenomena. "Even if he had done nothing else, the theory of the coral islands alone would have placed Darwin in the very front of investigations of nature" (Geikie).

This outspoken statement of a belief in evolution, published anonymously to protect Chambers’s reputation as a publisher, anticipated Darwin’s Origin by 16 years and generally prepared the public for Darwin’s theories. For a scientific book in the Victorian era, it became a sensational best seller. Authorship was not revealed until the 12th edition (1884) 13 years after Chambers’s death. Facsimile reprint, Leicester, Univ. Press, 1969. See M. Millhauser, Just before Darwin: Robert Chambers and ‘Vestiges’, Middletown, Wesleyan University Press, [1959].

The third and last of Darwin's geological reports on the Beagle voyage. In it he described the pampas, the plateaus and the Andres, showing how they had been gradually pushed up in the way that Charles Lyell surmised without the introduction of catastrophic events. The descriptions of secondary fossil shells from South America, illustrated in Sowerby's plates, are by Edward Forbes.

Owen’s vertebral theory of the origin of the skull, later refuted by Thomas Huxley and others.
"Owen began working systematically on problems of transcendental morphology in 1841, as part of his curatorial task to arrange the osteological collection of the Hunterian Museum. The osteological work was not published until 1853, but in the intervening years various spin-offs of this basic museum work appeared in print. . . . Owen extracted from the catalogue work his comprehensive account of transcendental osteology which he presented to the British Association in the form of a major report (1846); it was enormously detailed, densely packed with specifics, loaded with technical terms, and tedious to read. This report, with some additions, was published in book form under the title On the Archetype and Homologies of the Vertebrate Skeleton (1848). The following year, 1849, Owen expanded upon some parts of his BAAS Report in a lecture at the Royal Institution, published as On the Nature of Limbs. It was less overloaded with anatomical detail and nomenclature than his report, and more accessible to a wider audience" (Rupke, Richard Owen Victorian Naturalist, pp. 163-64)

This paper is sometimes referred to as the Sarawak Law paper since it was written while Wallace was on a specimen collecting expedition in the province of Sarawak (East Malayasian States) on the great island of Borneo. The paper has been misrepresented by certain historians as presenting a portion of the theory of natural selection. That is false; Wallace did not publish on natural selection until the Darwin-Wallace papers published in 1858 (No. 219).

The "law" states "The following law may be deduced from these facts: — Every species has come into existence coincident both in space and time with a pre–existing closely allied species."  

About this Malcolm Jay Kottler wrote to me in April, 2023, "Darwin did not see that Wallace was thinking in evolutionary terms in this paper. In his paper Wallace used the word 'created' a number of times--such as 'It is evidently possible that two or three distinct species may have had a common antitype, and that each of these may again have become the antitypes from which other closely allied species were created"--which Darwin interpreted as creationist, and not evolutionary, in meaning.

See John van Wyhe, "The impact of A. R. Wallace's Sarawak Law paper reassessed," Studies in History and Philosophy of Science Part: Studies in History and Philosophy of Biological and Biomedical Sciences, 60 (2016) 56-66.

In Omphalos, published in 1857, two years before the publication of Darwin's On the Origin of Species, Gosse attempted to reconcile the paleontological record with creationist religious beliefs by arguing that the fossil record was not evidence of evolution, but an act of creation by God to make the world appear older than it actually is. This tautology parallels how Gosse chose to explain why Adam, who could have had no mother, had a navel: Though Adam would have had no need of a navel, God gave him one anyway to give him the appearance of having human ancestry. Following this argument, the title of Gosse's book, Omphalos, means "navel" in Greek.

Digital facsimile from Biodiversity Heritage Library at this link.

The first printed exposition of the “Darwinian” theory of evolution by natural selection. Had not Wallace independently discovered the theory of natural selection, it is possible that the extremely cautious Darwin might never have published his evolutionary theories during his lifetime. However, Wallace conceived the theory during an attack of malarial fever in Ternate in the Mollucas (February, 1858) and sent a manuscript summary to Darwin, who feared that his discovery would be pre-empted. In the interest of justice Joseph Dalton Hooker and Charles Lyell suggested joint publication of Wallace’s paper, On the tendency of varieties to depart indefinitely from the original type, prefaced by a section of a manuscript of a work on species written by Darwin in 1844, when it was read by Hooker, plus an abstract of a letter by Darwin to Asa Gray, dated 1857, to show that Darwin’s views on the subject had not changed between 1844 and 1857.

The Darwin-Wallace paper was issued in five different forms, all from the same setting of type. Four of these resulted from the publishing customs of the Linnean Society of London, which issued the journal in three different printed wrappers, depending on whether members subscribed to the zoological or botanical parts alone or both parts together. The fourth form was publication in the annual volume of the Journal, "made up from reserved stock of the parts with new title pages, dated in the year of completion of the volume, and indexes. This again was available complete or as Zoology or Botany alone" (Freeman). The fifth form was the authors' offprint. That form is of the greatest rarity.

Prepared under the advice of Lyell and Hooker, and brought to press soon after publication of the joint paper by Darwin and Wallace (No. 219), this was Darwin’s greatest work and one of the most important books ever published. The whole edition of 1250 copies was sold on the day of publication.

The theory of evolution can be traced to the ancient Greek belief in the “great chain of being.” Darwin’s greatest achievement was to make this centuries-old “underground” concept acceptable to the scientific community by cogently arguing for the existence of a viable mechanism – natural selection – by which new species evolve over vast periods of time. Darwin’s influence on biology was fundamental, and continues to be felt today. He remains, with Albert Einstein, one of the best-known scientists of all time.

Facsimile reproduction, with introduction by E. Mayr, Cambridge, Mass., 1964. See R.B. Freeman, The works of Charles Darwin: an annotated bibliographical handlist. 2nd ed. Folkestone, Kent, Dawson: 1977. See the Online Variorum of Darwin's Origin of Species, edited by Barbara Bordalejo. This is a variorum edition of the six British editions of Darwin's Origin of Species, published between 1859 and 1872. It identifies and presents every change between the six editions. See the editor's Introduction. Digital facsimile of the 1859 edition from Darwin Online at this link.

The first important botanical work by a supporter of Darwin’s theory of evolution by natural selection. Hooker, a botanist and plant geographer, had been a close friend of Darwin for many years, and was aware of Darwin’s gradual progression toward a belief in the mutability of species, yet he did not begin fully to support Darwin’s views until shortly after the publication of the Origin of Species (1859). In his introduction to Flora Tasmaniae, the third volume of his massive Botany of the Antarctic Voyage of H. M. Discovery Ships ‘Erebus’ and ‘Terror’, Hooker publicly acknowledged his acceptance of Darwinian theory, which had come about “solely and entirely from an independent study of the plants themselves” (letter to W. H. Harvey, c. 1860). (This is a kind of offprint of a portion of No. 7448; it is sometimes viewed as a separate work.) 

Darwin's first work on plant fertilization and the first volume of evidence that he published to support the theories advanced in On the origin of species (1859). This was also the only book by Darwin that was issued by Murray in distinctive purple cloth (first edition only).

Extensively revised, and the first edition to include the "historical sketch" crediting the historical precursors to the theory of evolution by natural selection. Darwin added this chapter in response to writings by Samuel Butler and others.

Bates spent eleven years in the Amazon and there collected 8,000 species of insects new to science. In the above paper he clearly stated and solved the problem of “mimicry”, known today as “Batesian mimicry”. The superficial resemblance of a palatable species (mimic) to an unpalatable species (model) is a form of protective coloration that has evolved by natural selection. (See also No. 228.1)

This series of six lectures delivered to “working men” in November and December, 1862 includes Huxley’s first book-form exposition of Darwin’s theories, of which he was probably the greatest popular exponent. A prolific essayist as well as author of hundreds of scientific papers, Huxley was one of the most eloquent of all English writers on the natural sciences. 

Huxley showed that in the visible characters man differs less from the higher apes than do the latter from lower members of the same order of primates. He also provided the first thorough and detailed comparative description of the Neanderthal remains in English. The first issue of the first edition did not include a Table of Contents.

Lyell’s summary discussion of the evidence for human antiquity “introduced a wide readership to the new view and to the facts that supported it, thus laying the synthetic foundation for future work” (Grayson). This work also contained Lyell’s first published statements about Darwin’s theory of evolution by natural selection. Digital facsimile from the Internet Archive at this link.

Digital facsimile from the Internet Archive at this link.

In vol. 1 of this work written after Spencer read Darwin's On the origin of species, Spencer originated the expression "survival of the fittest." Spencer conceived that every species is endowed with its own type of physiological unit, each unit being capable, under certain circumstances, of reproducing the whole organism. Spencer set forth doctrines of evolution some years before the appearance of the Origin of species. 

Müller, the first German to support Darwin, studied the development of the Crustacea in Brazil and published some of his results in the above little book, which contains much original information. He realized the bearing of individual development on the theory of evolution. English translation as Facts and arguments for Darwin, London, 1869. Repr., 1968.

Wallace delivered this paper to the polygenist Anthropological Society of London on 1 March 1864. It represents “the first effort to connect natural selection to the touchy problem of the evolution of human races” (Wallace 1991, 26), a topic that Huxley broached in his Evidence of Man's Place in Nature (1863) but which Darwin avoided until his Descent of Man (1871).

Wallace argued that man is fundamentally different from all other species because of the nature of the human mind, which enabled him “to remove his body from the modifying influence of external conditions, and the cumulative action of natural selection.” Though Wallace shares credit with Darwin for the theory of evolution by natural selection, Wallace differed fundamentally from Darwin in his attempt to distinguish the effect of natural selection upon man from its effect on the rest of living things. 

Darwin's report on his discoveries concerning the adaptive value of climbing for certain plants, including the development of circumnutation. Darwin waited ten years to publish the first edition in book form (1875) with the same title. That edition included data published by Fritz Muller and Hugo de Vrie's as well as darwin's own folllow-up research. The illustrations in the book form edition were drawn by the author's son George Darwin.

Vol. 1. Fishes and reptiles; Vol. 2. Birds; Vol. 3. Mammals. The most important work on the subject after Cuvier, based entirely on personal observations.

Owen entitled his 40th and concluding chapter "Derivative hypothesis of life and species." Despite the major role he played in the mid-nineteenth century debate over evolution, Owen never wrote a major treatise on the subject, and this 40-page chapter represents his longest and most detailed statement of his position concerning the theory of evolution by natural selection. Contrary to popular belief, Owen was not an anti-evolutionist, but he held that Darwinian natural selection did not satisfactorily explain the process of speciation. Owen instead theorized that new species arose from “an innate tendency to deviate from parental type, operating through periods of adequate duration” (Derivative Hypothesis, p. 22). Owen believed that evolution was a teleological rather than an unguided process, “a movement towards a pre-ordained goal; and mutations were not randomly useful or useless, but a logical embroidering on the [fundamental] archetype” (Rupke, Richard Owen, pp 248-49).

Discovery of the Mendelian ratios, the most significant single achievement in the history of genetics. The story of how Mendel published his paper in this relatively obscure journal only to have his discovery ignored during his lifetime has been frequently retold. In 1900 Correns and de Vries (Nos. 239.01 and 239.1) rediscovered the Mendelian ratios almost simultaneously. William Bateson first translated the above work into English in J. Roy. Hort. Soc., 1901, 26, 1-32. The following year he published his first monograph on Mendel (No. 241).

Haeckel accepted the general principles of Darwinism, disagreeing on some points. He was the first to promote Darwin’s theories in Germany. This work contains the first statement of his theory that “ontogeny recapitulates phylogeny”. See No. 224.

Haeckel constructed the first of the now commonplace ancestral trees, depicting the evolution of life from the simplest organisms through 21 stages of development to modern man – the 22nd and final stage. Within this general scheme he created the concept of the Phylum (i.e. stem) to accommodate all organisms descended from a common form, and created the word Phylogeny to describe their evolutionary development from common form to distinct species. He suggested that within each species the term Ontogeny should describe the development of the individual from conception to maturity. From this he proposed his famous biogenetic law, “Ontogeny recapitulated Phylogeny”. English translation, 2 vols., London, 1876. Darwin wrote in The Descent of man (No. 227) “if [the English translation of] this work had appeared before my essay [Descent…] had been written, I should probably never have completed it. Almost all the conclusions at which I have arrived I find confirmed by this naturalist, whose knowledge on many points is much fuller than mine”. 

Haeckel differed from Darwin in advocating a polygenist theory of human evolution. He traced human lineage back to a hypothetical ancestral form, intermediate between humans and apes, that he named Pithecanthropus. “It was from the ‘Pithecanthropoi,’ Haeckel contended, that primeval humanity (which he termed Homo primigenius) was derived.... The various human races were considered to have been derived from Homo primigenius by natural selection, resulting in the formation of two quite divergent forms of humanity: (i) ‘the wooly-haired men’ (Ulotrichi); and (ii) ‘the straight-haired men’ (Lisotrichi). The Ulotrichi, Haeckel said, initially spread south from their primeval homeland, and then east and west. The remnants of the eastern branch being the peoples of New Guinea and Melanesia, while the negroes of Africa were considered representatives of the western branch. The remainder of modern humanity, the Lisotrichi, consisted of several divergent branches of what he called the ‘primeval Malays, or Promalays.’ The ‘Indo-Germanic race’ was a branch of the Lisotrichi, which he considered to have deviated furthest from the common ancestry. The chief representatives of this group were the Germans and English, who he said ‘are in the present age laying the foundation for a new period of higher mental development’” (Spencer, Ecce Homo [1986] 156.)

Darwin carried out numerous investigations with pigeons and various plants. He recognized continuous and discontinuous variation; he concluded that crossing tends to keep populations uniform.

Huxley proposed a close relationship between birds and dinosaurs after the discovery in Germany of the primitive fossil bird Archaeopteryx. He made detailed comparisons of Archaeopteryx with various prehistoric reptiles and found that it was most similar to dinosaurs like Hypsilophodon and Compsognathus. Digital facsimile from the Biodiversity Heritage Library at this link.

While Agassiz often wrote in general terms regarding his virulent opposition to Darwin's theory of evolution by natural selection, he provided his scientific rationale for that opposition only in an appendix to the French translation of his Essay on classification: Part 3, Chapter 7: Le Darwinisme. - Classification de Haeckel. Digital facsimile from the Biodiversity Heritage Library at this link. See Morris, P.J., "Louis Agassiz's additions to the French translation of his Essay on Classification," Journal of the History of Biology, 30 (1997) 121-134 . Morris's English translation is available from athro.com at this link.

Gegenbaur’s best work. He stressed the value of comparative anatomy as the basis of the study of descent, considering that knowledge of the relations of corresponding parts in different animals was more important even than comparative embryology in this respect.

Reprints, with important revisions and additions, nine important papers concerning natural selection, which had previously appeared in journals, and publishes for the first time a major paper on The limits of natural selection as applied to man. Unlike Darwin, Wallace believed that at some point during man’s history man had partially escaped natural selection, and that a “higher intelligence” had a part in the development of the human race.

Huxley was among those who refuted Owen’s theory of the vertebral skull.

This is really two works. The first demolished the theory that the universe was created for humans while in the second Darwin presented a mass of evidence in support of his earlier hypothesis regarding sexual selection. With respect to human origins, Darwin predicted that the ancestors of humanity would eventually be found in Africa, based on the extensive primate populations there. However, during the 19th and early 20th centuries paleoanthropologists focused their researches in Europe and Asia rather than Africa. This focus only very gradually changed after Raymond Dart discovered Australopithecus africanus in 1924.

Darwin examined the causes, physiological and psychological, of all the fundamental emotions in man and animals. He concluded that “the chief expressive actions exhibited by man and by the lower animals are now innate or inherited”, and that most of the movements of expression must have been gradually acquired. This is the only book by Darwin illustrated with photographs. It reproduces a number of photographs from Duchenne (No. 4973), and other photographs by Oscar Gustav Reijlander. Reprinted, New York, 1955. See P. Ekman (ed.): Darwin and facial expression: A century of research in review. New York, 1973.

Haeckel’s gastraea theory, which considers the two-layered gastrula the ancestral form of multicellular animals.

In this book Belt first described "the mutualistic relationship of certain Acacias and the ant we now know as Pseudomyrmex spinicola. These are a species of red myrmecophyte-inhabiting neotropical ants which are found only in Nicaragua and Costa Rica. They live in the thorns of a tropical tree, Acacia collinsii, feeding on nectaries along with the protein and lipid-rich pods produced by the plant for the ants and now known as Belsian bodies (or Beltian bodies) in honor of Belt" (Wikipedia article on Thomas Belt, accessed 07-31-2016).

Digital facsimile from the Biodiversity Heritage Library at this link.

Dohrn’s theory of change of function as the origin of evolutionary novelties.

Bates’s theory of mimicry did not account for the superficial resemblances between two or more unpalatable species. Müller explained such mimicry, known today as “Müllerian mimicry”. A predator must learn which potential prey are palatable. The coloration of an unpalatable species serves as warning colouration to predators. When warning colouration is shared by two or more unpalatable species, the warning colours are recognized more quickly by the predator and the number of individuals destroyed in each species is reduced while the predator learns. Müller's account contained one of the earliest uses of a mathematical argument in evolutionary ecology to show how powerful the effect of natural selection would be:

"Instead of a general deduction, which is by the way extremely simple, I give an example. There may in a certain area live two unpalatable species; 10,000 individuals of the first species, and 2000 of the second. The predators living in the same area may eat per year 1200 individuals of each [distinct] unpalatable species per year until they avoid it as such. Each species would lose this many if they appeared different; but if they are very similar so that experience with one species benefits the other, then the first species will lose 1000 and the second 200 individuals. The first species therefore will gain because of its similarity 200 individuals, or 2 % of the total number, the second will however gain 1000 individuals, which is 50% of the total number - from this consideration it follows further that probably in some cases (for example Thyridia and Ituna) the question which one of both species is the original and which one is the copy is an irrelevant question; each had an advantage from becoming similar to the other; they could have converged on each other" (http://www.ucl.ac.uk/taxome/jim/Mim/muller1878.html, accessed 03-2018).

Krause's short biography originally appeared in the German evolutionary periodical Kosmos in February 1879. In this translation Darwin added a biographical contribution that is longer than Krause's, i.e. 127pp by Darwin versus 89pp. by Krause. Darwin paid frequent tribute to his grandfather Erasmus, but denied that Erasmus's ideas had influenced him significantly in the development of the theory of evolution by natural selection. Digital facsimile of the copy Darwin presented to his daughter Henrietta Litchfield from the Internet Archive at this link.

"In 1880, Wallace published the book Island Life as a sequel to The Geographical Distribution of Animals. It surveyed the distribution of both animal and plant species on islands. Wallace classified islands into three different types. Oceanic islands, such as the Galapagos and Hawaiian Islands (then known as the Sandwich Islands) formed in mid-ocean and never part of any large continent. Such islands were characterised by a complete lack of terrestrial mammals and amphibians, and their inhabitants (with the exceptions of migratory birds and species introduced by human activity) were typically the result of accidental colonisation and subsequent evolution. He divided continental islands into two separate classes depending on whether they had recently been part of a continent (like Britain) or much less recently (like Madagascar) and discussed how that difference affected the flora and fauna. He talked about how isolation affected evolution and how that could result in the preservation of classes of animals, such as the lemurs of Madagascar that were remnants of once widespread continental faunas. He extensively discussed how changes of climate, particularly periods of increased glaciation, may have affected the distribution of flora and fauna on some islands, and the first portion of the book discusses possible causes of these great ice ages. Island Life was considered a very important work at the time of its publication. It was discussed extensively in scientific circles both in published reviews and in private correspondence^{[126]" (Wikipedia article on Alfred Russel Wallace, accessed 02-2017).}

Includes the first editon of Darwin's most significant contribution to psychology. This was part of Chapter 10 of Darwin's unpublished "big book" on the origin of species. Romanes attempted, with Darwin, to develop a theory of mental evolution in which development of successively higher stages of intelligence, including that of man, could be explained in terms of natural, historical causes. Digital facsimile from the Biodiversity Heritage Library at this link.

By “amphimixis” Weismann meant the union of the two parent germs, which he considered the principal source of heritable variation in evolution by natural selection. English translation in Weismann’s Essays upon Heredity, Vol. 2, Oxford, 1892.

Weismann produced experimental evidence that acquired characters are not transmitted.

Bateson was convinced that discontinuity was the more important type of variation among animals and plants “in some unknown way a part of their nature and not directly dependent upon natural selection at all”. He showed that Darwin’s concept of variation needed modification.

Wilson emphasized the function of cytology in the study of embryology, heredity, evolution and general physiology. The above work has been called the single most influential treatise on cytology of the 20th century. The third edition was extensively revised and enlarged as The cell in development and heredity, 1925. 

The Baldwin effect. "In evolutionary biology, the Baldwin effect describes the effect of learned behavior on evolution. In brief, James Mark Baldwin suggested that an organism's ability to learn new behaviors (e.g. to acclimatise to a new stressor) will affect its reproductive success and will therefore have an effect on the genetic makeup of its species through natural selection. Though this process appears similar to Lamarckian evolution, Lamarck proposed that living things inherited their parents' acquired characteristics. The Baldwin effect has been independently proposed several times, and today it is generally recognized as part of the modern evolutionary synthesis" (Wikipedia article on Baldwin effect, accessed 04-2017). Digital text of the paper from brocku.ca at this link.

Presents virtually all of Huxley's scientific papers arranged in chronological order, as well as reports of his Royal Institution Friday Evening Discourses. The final supplemental volume contains the remainder of Huxley’s survey memoir on fossil fishes, along with three papers not collected elsewhere.

Davenport introduced statistical methods into American evolutionary studies.

More support for the Mendelian law of inheritance was provided by Johannsen, a Danish botanist, who showed that in certain self-fertilizing plants a pure line of descendants can be maintained indefinitely, in which case natural selection is not effective, selection depending upon genetic variability. He introduced the term “gene” in 1909.

See also the digital edition and virtual reconstruction of the surviving books owned by Charles Darwin from the Biodiversity Heritage Library at this link. This BHL special collection draws on original copies and surrogates from other libraries. It also provides full transcriptions of his annotations and marks. "In this first release (2011) we provide 330 of the 1480 titles in his library, concentrating on the most heavily annotated books." 

In this work Johannsen coined the term “gene” as the “underlying structure in the organism, that which was transmitted during hybridzation.” He also coined the term "phenotype" to express what is actually observed and can be measured, in contrast to "genotype" that he coined “to express the underlying constitution of the organism from which development of the organism begins" (Brock).

This massive work with 100 plates including 600 images, was the first large-scale investigation of species differences at the molecular level. Digital facsimile from the Internet Archive at this link.

Wegener originated the theory of continental drift in this paper on the origin of continents, which he conceived after being struck by the apparent correspondence in the shapes of the coastlines on the west and east sides of the Atlantic, and supported with extensive research on the geological and paleontological correspondences between the two sides. He postulated that 200 million years ago there existed a supercontinent (“Pangaea”), which began to break up during the Mesozoic era due to the cumulative effects of the “Eötvös force,” which drives continents towards the equator, and the tidal attraction of the sun and moon, which drags the earth’s crust westward with respect to its interior. Wegener’s theory attracted little interest until 1919, when he published the second edition of his treatise Die Entstehung der Kontinente und Ozeane.

Key documents from the Scopes Trial. Digital facsimile from the Hathi Trust at this link.

Classic study of the evolution of the central nervous system in the higher mammals. Digital facsimile from the Internet Archive at this link.

The first coherent general algebraic analysis of Mendelian population behavior. The work contains Fisher’s rigorous development of his “fundamental theorem of natural selection”–”the rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time.”

"Fisher's principle is an evolutionary model that explains why the sex ratio of most species that produce offspring through sexual reproduction is approximately 1:1 between males and females. It was famously outlined by Ronald Fisher in his 1930 book The Genetical Theory of Natural Selection^[1] (but incorrectly attributed to Fisher as original^[2]). Nevertheless, A. W. F. Edwards has remarked that it is "probably the most celebrated argument in evolutionary biology".^[2] Specifically, Fisher couched his argument in terms of parental expenditure, and predicted that parental expenditure on both sexes should be equal. Sex ratios that are 1:1 are hence known as "Fisherian", and those that are not 1:1 are "non-Fisherian" or "extraordinary" and occur because they break the assumptions made in Fisher's model.^[3] Many eusocial wasps, such as the Polistes fuscatus and the Polistes exclamans seem to exhibit such a ratio at times." (Wikipedia article on Fisher's principle, accessed 03-2017).

Along with Wright (No. 253.1) and Haldane (No. 254), Fisher established mathematical population genetics.

First detailed presentation of Wright’s quantitative theory of the effects of mutation, migration, selection, and population size on changes in gene frequencies in populations. Digital facsimile from Genetics.org at this link.

A study of the relationship of Man to the other primates, from the physiological and biochemical standpoint. Zuckerman’s work is considered the first adequate interpretation of simian society. 2nd ed., 1980.

Haldane’s summary of his mathematical theory of natural selection. The detailed mathematical theory appeared as Mathematical theory of natural and artificial selection, first published (Pt. I) in Trans. Camb. philos. Soc.,1924, 23, 19-41, and (Pts. II-IX) in Proc. Camb. philos. Soc., vol. 1, 23, 26, 27, 28. Pt. X appeared in Genetics, 1934, 19, 412-29.

Gause developed the concept of competitive exclusion as formulated by Volterra.

Dobzhansky, an emigrant from the Soviet Union to the United States, and a postdoctoral worker in Thomas Hunt Morgan's fruit fly lab, was one of the first to apply genetics to natural populations. He worked mostly with Drosophila pseudoobscura. Genetics and the Origin of Species "was a key step in bridging the gap between population geneticists and field naturalists. It presented the conclusions reached by Fisher, Haldane, and especially Wright in their highly mathematical papers in a form that was easily accessible to others. It also emphasized that real world populations had far more genetic variability than the early population geneticists had assumed in their models, and that genetically distinct sub-populations were important. Dobzhansky argued that natural selection worked to maintain genetic diversity as well as driving change^{" ( Wikipedia article on Modern Synthesis, accessed 03-2017).}

Published during WWII, Cott's book was the first major work on camouflage in zoology, appreciated by zoologists for its scientific information and carried by many allied soldiers during the war for survival purposes. The Wikipedia analysis of this book is especially valuable. Digital facsimile of the 1957 slightly corrected reprint from the Internet Archive at this link.

The work which defined the modern synthesis of evolutionary biology of the early 20th century.

One of the canonical publications of the modern evolutionary synthesis. Mayr discussed the different ways different investigators identify species, and he characterized these different approaches as different species concepts. He also argued strongly for what came to be called a Biological Species Concept (BSC)—that a species consists of populations of organisms that can reproduce with one another, and that are reproductively isolated from other such populations.

 Simpson's seminal contribution to the modern evolutionary synthesis integrated the facts of paleontology with those of genetics and natural selection.

"Simpson argued that the microevolution of population genetics was sufficient in itself to explain the patterns of macroevolution observed by paleontology. Simpson also highlighted the distinction between tempo and mode. "Tempo" encompasses "evolutionary rates . . . their acceleration and deceleration, the conditions of exceptionally slow or rapid evolutions, and phenomena suggestive of inertia and momentum", while "mode" embraces "the study of the way, manner, or pattern of evolution, a study in which tempo is a basic factor, but which embraces considerably more than tempo."

Simpson's Tempo and Mode attempted to draw out several distinct generalizations:

• Evolution's tempo can impart information about its mode.
• Multiple tempos can be found in the fossil record (bradytelic, tachytelic, horotelic).
• The facts of paleontology are consistent with the genetical theory of natural selection. Moreover, theories such as orthogenesis, Lamarckism, mutation pressures, and macromutations either are false or play little to no role.
• Most evolution—"nine-tenths"—occurs by the steady phyletic transformation of whole lineages (anagenesis). This contrasts with Ernst Mayr's interpretation of speciation by splitting, particularly allopatric and peripatric speciation.
• The lack of evidence for evolutionary transitions in the fossil record is best accounted for, first, by the poorness of the geological record, and, second, as a consequence of quantum evolution (which is responsible for "the origin of taxonomic units of relatively high rank, such as families, orders, and classes"). Quantum evolution built upon Sewall Wright's theory of random genetic drift." (Wikipedia article on Tempo and Mode in Evolution, accessed 03-2017).

The first comprehensive exposition of the relationship between genetics and natural selection in plants, and the most imporant book on plant evolution published during the 20th century.  Stebbins combined genetics and natural selection to describe plant speciation. His work was one of the main publications that formed the core of the modern evolutionary synthesis and still provides the conceptual framework for research in plant evolutionary biology.

"According to Ernst Mayr, 'Few later works dealing with the evolutionary systematics of plants have not been very deeply affected by Stebbins' work"^[2]....

"The 643-page book cites more than 1,250 references and was the longest of the four books associated with the modern evolutionary synthesis. The other key works of the modern evolutionary synthesis, whose publication also followed their authors' Jesup lectures, are Theodosius Dobzhansky's Genetics and the Origin of Species, Ernst Mayr's Systematics and the Origin of Species and George Gaylord Simpson's Tempo and Mode in Evolution. The great significance of Variation and Evolution in Plants is that it effectively killed any serious belief in alternative mechanisms of evolution for plants, such as Lamarckian evolution or soft inheritance, which were still upheld by some botanists.^[2] Stebbins book Flowering Plants: Evolution Above the Species Level was published in 1974 and was based on the Prather Lectures which he gave at Harvard. It is considered as an update to Variation and Evolution." (Wikipedia article on Variation and Evolution in Plants, accessed 02-2017).

This play about the Scopes Trial that concerned creationism versus evolution was the subject of numerous film adaptations including the most famous one first screened in 1960 starring Spencer Tracy and Fredric March.

Allison was the first to connect a hereditary disease (sickle cell disease) to an infectious disease (malaria). He proved that heterozygous and homozygous individuals to the sickle cell trait or disease respectively show a resistance to malarial illness which allows them to survive while others die. The sickle cell individuals then survive to puberty, reproduce and pass down their ‘beneficial’ trait. Digital facsimile from PubMedCentral at this link.

In 1956 Allison published a semi-popular version of this research as "Sickle cells and evolution," Scientific American, 195 (1956) 87-94.

(Thanks to Juan Weiss for this reference and its interpretation.)

In 2014 Allison was interviewed concerning his sickle cell research in this video from hhmi biointeractive:

In this paper Brown and Wilson defined character displacement as follows: "Two closely related species have overlapping ranges. In the parts of the ranges where one species occurs alone, the populations of that species are similar to the other species and may even be very difficult to distinguish from it. In the area of overlap, where the two species occur together, the populations are more divergent and easily distinguished, i.e., they 'displace' one another in one or more characters. The characters involved can be morphological, ecological, behavioral, or physiological; they are assumed to be genetically based."

Condensed and extensively revised as Populations, species and evolution. Cambridge: Belknap Press of Harvard University Press, 1970.

Using complex mathematics, Motoo Kimura calculated that genomes constantly undergo a remarkably high number of mutations per unit of time. He wrote, "Calculating the rate of evolution in terms of nucleotide substitutions seems to give a value so high that many of the mutations involved must be neutral ones."  Motoo Kimura's theory holds that most evolutionary changes occur at the molecular level, and that most of the variation within and between species is due to random genetic drift of mutant alleles that are selectively neutral -- neither advantageous or disadvantageous. Kimura does not discuss natural selection in his paper; however, his theory does not contradict traditional Darwinian theory that evolution occurs through the natural selection of non-neutral, advantageous variants in a given population. Kimura expanded his theory in his 1983 book The neutral theory of molecular evolution.

In 2021 a digital facsimile of the 1968 paper was available from blackwellpublishing.com at this link.

(Thanks to Juan Weiss for this reference and its interpretation.)

The theory of punctuated equilibrium or punctuated equilibria in evolution. This theory argues that once species appeared in the the fossil record they became stable, showing little net evolutionary change for most of their geological history. This state they called stasis. When significant evolutionary change occurred, the theory states that it is generally restricted to rare and geologically rapid events of branching speciation called cladogenesis. Cladogenesis is the process by which a species splits into two distinct species, rather than one species gradually transforming into another. Eldredge and Gould argued that the degree of gradualism in evolution commonly attributed to Darwin is virtually nonexistent in the fossil record, and that stasis dominates the history of most fossil species. In 2016 the paper and Eldredge and Gould was available from blackwellpublishing.com at this link.

In addition to a frequently original study of the development of Darwin's psychological theories, the authors publish for the first time two extremely significant manuscript notebooks by Darwin written in 1837. These notebooks, which the authors supplement with notes and commentary, provide the earliest available insight into the origins of Darwin's views on human and comparative psychology. Some of the ideas they record were later developed in The descent of man and The expression of emotions in man and animals. Also the notebooks prove something that Darwin never publically admitted: the belief that man and the great apes descended from a common ancestor was the core of his theory of human evolution as early as 1837. Furthermore, the notebooks show that Darwin recognized the relationship between animal and human sexual behavior during the height of Victorian prudery. No wonder he never developed in print such theories as "Our descent, then is the origin of our evil passions!!− The Devil under form of Baboon is our grandfather!" (M. Notebook, p. 123).

http://www.darwinproject.ac.uk/"

"Search over 12000 letters and articles..."

Integration of biological and evolutionary theory with the study of social behavior and social organization of animal populations.

In 1975 Goodman and his collaborators used sequence data to reconstruct the evolutionary history of hemoglobin (including possible ancestral sequences) and analyze which sites on the hemoglobin complex had evolved at which stages. Goodman called this the first "hard evidence of Darwinian evolution".

The authors showed that the Plasmodium vivax parasite requires the Fya/Fyb Duffy antigen/chemokine receptor on the surface of red blood cells for penetration of human red blood cells. Because most African and American blacks have the FyFy genotype they are resistant to infection by P. vivax.

(Thanks to Juan Weiss for this reference and its interpretation.)

This bibliography has been extensively supplemented by the Freeman Bibliographical Database at Darwin Online edited by John van Wyhe. "The database has been supplemented by the entries from unpublished manuscript corrections by Freeman and those in:
Freeman. 1986. The works of Charles Darwin: an annotated bibliographical handlist. Additions and Corrections to Second Edition of 1977 to 1 January, 1986. University College London: for the author; as well as Freeman. 1986. Darwin in Chinese. Archives of Natural History 13 (1): 19-24; P. J. P. Whitehead. 1988. Darwin in Chinese: some additions. Archives of Natural History 15 (1): 61-62; the bibliography of The Correspondence of Charles Darwin; and subsequent research by John van Wyhe, Kees Rookmaaker, Angus Carroll, J. David Archibald and other contributors."

An interpretive history of what Mayr calls “ultimate” explanations in biology, reflecting Mayr’s expertise in systematics, evolution, and genetics.

A pioneering work on the evolution of the human mind. Eccles synthesized comparative anatomy--especially brain anatomy--with evidence from paleontology and archaeology, and brain physiology (especially the physiology of language), and philosophy--all within the framework of Darwinian evolutionary theory, making allowance for the latest critcal developments.

The first book to apply allometry— one definition of which is the study of the growth rate of an organism's parts in relation to the whole — to studies of the evolution, morphology, physiology, and reproduction of plants.

On the evolution of birds and avian flight. Feduccia is best known for his criticisms of the hypothesis, accepted by many paleontologists, that birds originated from and are deeply nested within Theropoda, and are therefore living theropod dinosaurs. "He has argued for an alternative theory in which birds share a common stem-ancestor with theropod dinosaurs among more basal archosaurian lineages, with birds originating from small arboreal archosaurs in the Triassic" (Wikipedia article on Alan Feduccia, accessed 04-2017). 

https://mathcs.clarku.edu/huxley/

"Those merely interested in Huxley and scholars engaged in research on him, on Darwinism, on Victorian culture, on the history of science, and on topics such as those noted will find that THE HUXLEY FILE, in which reside over 1000 items, justifies its title. The 1000 figure covers 680 pieces of published and unpublished text by THH; more than 150 pictures by and on him, with an uncounted number of pictures in text by and for him; and 120 commentaries on him. Cybernauts will find here

• the entirety of the nine-volume Collected Essays;
• 40 selections from the five-volume Scientific Memoirs;
• and also a large number of Huxley essays that were never collected, from The Westminster Review, Youth's Companion, etc.; among these, the most important hidden pieces are the three essays he wrote for a club, The Metaphysical Society, on whether a frog has a soul, whether immortality is reasonable, whether Jesus was actually resurrected;
• several pieces that exist only in draft form, such as his teenage journal "Thoughts and Doings," "Agnosticism–A Fragment" and "The Natural History of Christianity";
• letters published in The Times, Nature, etc.; most of the letters appear in Leonard Huxley, ed., The Life and Letters of Thomas Huxley and Julian Huxley, ed., Thomas Henry Huxley's Diary of the Voyage of H.M.S. Rattlesnake –which is the best provider of THH's diary items; some of the letters come from collections in libraries around the world.
• a cornucopia of illustrations ranging from his doodles and sketches of natives to cartoons and portraits of him, illustrations not attached to any text, and a number illustrating texts such as Man's Place in Nature and Oceanic Hydrozoa.
• 120 commentaries on him, some praising his work, others attacking it, such as Powheads, Porwiggles and Protoplasm."

http://darwin-online.org.uk/AboutUs.html

 Darwin's Complete Publications
    Books Origin of Species, Voyage of the Beagle, Descent of Man...
    Articles Volcanic, Darwin-Wallace paper...
    Published Letters Life and letters, Darwin & Henslow...
    Published Manuscripts Autobiography, Beagle diary (audio)...

• Darwin's Private Papers & Manuscripts 
    Notebooks, Journal, student bills, marriage notes,
    Geological diary, Emma's diaries, Annie Darwin...

• Supplementary 
    The Beagle Library
    Beagle specimens
    Reviews & Responses 
    Obituaries & Recollections
    Works about Darwin Companion, Beagle itinerary...

A "technical book on macroevolution and the historical development of evolutionary theory.^[1] The book was twenty years in the making,^[2]published just two months before Gould's death.^[3] Aimed primarily at professionals,^[4] the volume is divided into two parts. The first is a historical study of classical evolutionary thought, drawing extensively upon primary documents; the second is a constructive critique of the modern evolutionary synthesis, and presents a case for an interpretation of biological evolution based largely on hierarchical selection, and the theory of punctuated equilibrium (developed by Niles Eldredge and Gould in 1972).^{[5]" (Wikipedia article on The Structure of Evolutionary Theory, accessed 03-2017).}

Through their more than 40 year study of Darwin's finches on the Island of Daphne Major in the Galapagos, the Grants demonstrated how natural selection can drive rapid changes in body and beak size in response to changes in the food supply. In the process the Grants elucidated the mechanisms by which new species arise and how genetic diversity is maintained in natural populations. Their results, which show that the effects of natural selection can be seen within a single lifetime, or sometimes within a couple of years, are in distinct contrast to the theories of Charles Darwin who thought that natural selection required extensive periods of time for its operation.

(Thanks to Juan Weiss for this reference and its interpretation.)

In 2004 Shubin, Daeschler and Jenkins discovered the first well-preserved Tiktaalik fossils in on Ellesmere Island in Nunavut, Canada. Tiktaalik is a non-tetrapod member of Osteichthyes (bony fish) from the late Devonian period about 375 million years before present. It is complete with scales and gills, but has a triangular, flattened head and unusual, cleaver-shaped fins. Its fins have thin ray bones for paddling like most fish, but they also have sturdy interior bones that would have allowed Tiktaalik to prop itself up in shallow water and use its limbs for support as most four-legged animals do. The fins and other mixed characteristics mark Tiktaalik as a crucial transition fossil, a link in evolution from swimming fish to four-legged vertebrates. 

Order of authorship in the original publication: Shubin, Daescher, Jenkins.

(Thanks to Juan Weiss for this reference and its interpretation.)

The authors showed that:
1) This transitional species had a set of features representing a major departure from the pattern in more primitive sarcopterygian fishes.
2) They presented data to indicate that Tiktaalik lived in a low gradient, meandering fluvial system within a subtropical to tropical climactic belt.
3) In this setting this species developed new mechanisms of head movement, respiration and body support; it could lift itself from the ground, enabling it to emerge from the water and ambulate on the ground, since it was endowed with an abundance of chest muscles.
4) The species had expanded gular plates and robust branchial elements that provided it with a mechanical basis for buccal pumping for lungs as well as gills. These elements assumed a
predominant respiratory function for air breathing.
5) Tiktaalik, unlike a fish, had a flat head, and eyes on top of its head and a neck. Thus Tiktaalik’s head architecture resembled that of the present day crocodile.

Order of authorship in the original publication: Daeschler, Shubin, Jenkins.

(Thanks to Juan Weiss for this reference and its interpretation.)

"Our project has so far obtained electronic copies of 5,688 letters, of which 2,748 were written by Wallace and 2,159 were sent to him. The remaining 781 are third party letters which either pertain to him, or were written by Wallace's close relatives and contain information useful to scholars interested in his life. The letters were found in 245 public and private collections around the world, and in 245 articles and books" (accessed 10-2021).

https://www.kew.org/science/our-science/projects/joseph-hooker-correspondence-project

"Sir Joseph Dalton Hooker (1817 – 1911) was a trailblazing botanist and explorer and Kew’s second Director. Detailing plant diversity and economic botany throughout his many expeditions, he remains an influential figure to modern botanical science. 

"During his career he was also a prolific correspondent, writing to family, friends and colleagues, including Charles Darwin, and we are fortunate to hold an extensive archival collection at Kew. The Joseph Hooker Correspondence project is working to make his letters held in Kew’s archive, and other institutions’, available online. The project originally began with a partnership between Kew and the University of Sussex to produce digital images and full transcriptions of Hooker's Indian letters. Staff at Kew are continuing the project with the digitisation and transcription of further series of Hooker's correspondence. A team of expert remote volunteers transcribe the letters.

"The formation of this online repository, comprised largely of previously unpublished archive material, is intended to facilitate academic research in such fields as botany and other natural sciences, horticulture, British imperialism, garden history, the history of science and the history of the Royal Botanic Gardens, Kew. Kew also hopes to bring knowledge of Joseph Hooker to a wider audience and to extend awareness of the extent and significance of his work."

"Currently available online are:
•    Letters from Hooker’s Expedition to India (1847-1851), including accounts of his pioneering exploration and plant hunting in the Himalayas.
•    A series primarily composed of letters from Hooker to pre-eminent American botanist Asa Gray, with whom he went on a plant hunting tour of America in 1877 and shared a lifelong scientific dialogue.
•    Letters written by Hooker during his time as assistant surgeon and unofficial botanist to James Clark Ross’s expedition of discovery to Antarctica (1839-1843)
•    Other letters have been digitised and transcribed and will be available shortly.." (accessed 10-2021)

[Start date of this project is not posted on its website; to fit this into the chronology I have estimated the date at 2010.]

http://wallace-online.org/

"Wallace Online is the first complete edition of the writings of naturalist Alfred Russel Wallace, including the first compilation of his specimens. The project is directed by John van Wyhe, assisted by Kees Rookmaaker, at the National University of Singapore, in collaboration with the Wallace Page by Charles H. Smith.

Biography

Illustrations

Wallace in Singapore

About the project

Acknowledgements

Quick links: Wallace's books, book chapters, articles
Amazon, Sarawak law, Darwin-Wallace paper, Malay Archipelago, Darwinism, My Life, Letters and reminiscences.
To search Wallace's complete works (and not other authors) click Advanced Search."

Chapter one is "The history of placental investigations."

The authors sequenced the genome of 120 individuals representing all of Darwin’s finches. They found that a 240 kilobase haplotype encompassing the ALX1 gene, which encodes a transcription factor affecting craniofacial development, is strongly associated with beak shape diversity across Darwin’s finch species, as well as the medium ground finch (Geospiza fortis), a species that the Grants observed undergoing rapid evolution of beak morphology in response to the environmental changes described in their 2006 paper.
The authors saw variants of this gene in the finches, each of which encoded for a different type of beak morphology. These variants had arisen during natural selection processes.

Order of authorship in the original publication: Lamichhaney, Berglund, .... Grant, Grant.

(Thanks to Juan Weiss for this reference and its interpretation.)

Researching how the malarial mosquito A. gambiae developed resistance to common pyrethroid insecticides, the authors discovered how natural selection had enabled this insect population to develop resistance. They analyzed the gene-expression profiles of insecticide resistant A. gambiae populations from Burkina Faso and Côte d'Ivoire, finding higher than normal expression of genes that encode a family of chemosensory proteins, called sensory appendage proteins (SAPs). This protein specifically binds to pyrethroids that penetrate the moquito's hard exterior when it lands on a bed net (mosquito net), and thus prevents the insecticide from exerting its toxic effect by sequestering it and preventing its action on the mosquito's nervous system by promoting the breakdown of the pyrethrin. The authors also found that the expression of this protein is enhanced in the legs of the mosquito and mostly at the tips where the legs come in contact with the bed net. (Order of authorship in the original paper: Ingham, Anthousi, Douris, et al.)

(Thanks to Juan Weiss for this reference and its interpretation.)