Ernst Heinrich Philipp August Haeckel (/ˈhɛkəl/;[1]German:[ɛʁnstˈhɛkl̩]; 16 February 1834 – 9 August 1919)[2] was a Germanzoologist,naturalist,eugenicist,philosopher, physician, professor,marine biologist and artist. He discovered, described and named thousands of new species, mapped agenealogical tree relating all life forms and coined many terms inbiology, includingecology,[3]phylum,[4]phylogeny,[5]ontogeny,[6] andProtista.[7] Haeckel promoted and popularisedCharles Darwin's work in Germany[8] and developed the disproven but influentialrecapitulation theory ("ontogeny recapitulates phylogeny"), wrongly claiming that an individual organism's biological development, orontogeny, parallels and summarizes its species' evolutionary development, orphylogeny, using incorrectly drawn images of human embryonic development. Whether they were intentionally falsified, or drawn poorly by accident is a matter of debate.[9]
The published artwork of Haeckel includes over 100 detailed, multi-colourillustrations of animals and sea creatures, collected in hisKunstformen der Natur ("Art Forms of Nature"), a book which would go on to influence theArt Nouveau artistic movement. As a philosopher, Ernst Haeckel wroteDie Welträthsel (1895–1899; in English:The Riddles of the Universe, 1900), the genesis for the term "world riddle" (Welträtsel); andFreedom in Science and Teaching[10] to support teaching evolution.
Ernst Haeckel was born on 16 February 1834, inPotsdam (then part of theKingdom of Prussia).[13]In 1852, Haeckel completed studies at theDomgymnasium, the cathedral high-school ofMerseburg.[14][better source needed] He then studied medicine in Berlin andWürzburg, particularly withAlbert von Kölliker,Franz Leydig,Rudolf Virchow (with whom he later worked briefly as assistant), and with the anatomist-physiologistJohannes Peter Müller (1801–1858).[14] Together withHermann Steudner he attendedbotany lectures in Würzburg. In 1857 Haeckel attained a doctorate in medicine, and afterwards he received the license to practice medicine. The occupation of physician appeared less worthwhile to Haeckel after contact with suffering patients.[14]
From 1866 to 1867 Haeckel made an extended journey to theCanary Islands withHermann Fol. On 17 October 1866 he arrived in London. Over the next few days he metCharles Lyell, and visitedThomas Huxley and family at their home. On 21 October he visitedCharles Darwin atDown House in Kent.[16] In 1867 he married Agnes Huschke. Their son Walter was born in 1868, their daughters Elizabeth in 1871 and Emma in 1873.[14] In 1869 he traveled as a researcher toNorway, in 1871 toCroatia (where he lived on the island ofHvar in a monastery),[17] and in 1873 toEgypt,Turkey, andGreece.[14] In 1907 he hada museum built inJena to teach the public aboutevolution. Haeckel retired from teaching in 1909, and in 1910 he withdrew from theEvangelical Church of Prussia.[14]
In later life
On the occasion of his 80th birthday celebration he was presented with a two-volume work entitledWas wir Ernst Haeckel verdanken (What We Owe to Ernst Haeckel), edited at the request of the German Monistenbund by Heinrich Schmidt of Jena.[18][19]
In 1864, his first wife, Anna Sethe, died. Haeckel dedicated some species of jellyfish that he found beautiful (such asDesmonema annasethe) to her.[20][21]
Haeckel's second wife, Agnes, died in 1915, and he became substantially frailer, breaking his leg and arm.[14] He sold his "Villa Medusa" inJena in 1918 to theCarl Zeiss foundation, which preserved his library.[14] Haeckel died on 9 August 1919.[22]
InMonism as Connecting Religion and Science (1892), he argued in favor ofmonism as the view most compatible with the current scientific understanding of the natural world. His perspective of monism was pantheistic and impersonal.
The monistic idea of God, which alone is compatible with our present knowledge of nature, recognizes the divine spirit in all things. It can never recognise in God a "personal being," or, in other words, an individual of limited extension in space, or even of human form. God is everywhere.[23]
Haeckel's affinity for the GermanRomantic movement, coupled with his acceptance of a form ofLamarckism, influenced his political beliefs. Rather than being a strictDarwinian, Haeckel believed that the characteristics of an organism were acquired through interactions with the environment and thatontogeny reflectedphylogeny. He saw thesocial sciences as instances of "applied biology", and that phrase was picked up and used forNazi propaganda.[15]
He was the first person to use the term "first world war" aboutWorld War I.[27]
However, Haeckel's books were banned by theNazi Party, which refused Monism and Haeckel's freedom of thought. Moreover, it is worth mentioning that Haeckel had often overtly recognized the great contribution of educated Jews to the German culture.[28]
Sea anemones from Ernst Haeckel'sKunstformen der Natur (Art forms of Nature) of 1904
Haeckel was azoologist, an accomplished artist and illustrator, and later a professor ofcomparative anatomy. Although Haeckel's ideas are important to the history ofevolutionary theory, and although he was a competentinvertebrateanatomist most famous for his work onradiolaria, many speculative concepts that he championed are now considered incorrect. For example, Haeckel described and named hypothetical ancestralmicroorganisms that have never been found.[29]
He was one of the first to considerpsychology as a branch ofphysiology. He also proposed the kingdomProtista[14] in 1866. His chief interests lay inevolution and life development processes in general, including development of nonrandom form, which culminated in the beautifully illustratedKunstformen der Natur (Art forms of nature). Haeckel did not supportnatural selection, rather believing inLamarckism.[30]
Haeckel advanced a version of the earlierrecapitulation theory previously set out byÉtienne Serres in the 1820s and supported by followers ofÉtienne Geoffroy Saint-Hilaire includingRobert Edmond Grant.[31] It proposed a link betweenontogeny (development of form) andphylogeny (evolutionary descent), summed up by Haeckel in the phrase "ontogeny recapitulates phylogeny". His concept of recapitulation has been refuted in the form he gave it (now called "strong recapitulation"), in favour of the ideasfirst advanced by Karl Ernst von Baer. The strong recapitulation hypothesis views ontogeny as repeating forms of adult ancestors, while weak recapitulation means that what is repeated (and built upon) is the ancestral embryonic development process.[32] Haeckel supported the theory withembryo drawings that have since been shown to be oversimplified and in part inaccurate, and the theory is now considered an oversimplification of quite complicated relationships, however comparison of embryos[8] remains a powerful way to demonstrate that all animals are related. Haeckel introduced the concept ofheterochrony, the change in timing ofembryonic development over the course of evolution.[33][34]
Haeckel (left) withNicholai Miklukho-Maklai, his assistant, in theCanaries, 1866Portrait of two ''P. alalus'', speculative species
Haeckel was a flamboyant figure, who sometimes took great, non-scientific leaps from available evidence. For example, at the time when Darwin publishedOn the Origin of Species by Means of Natural Selection (1859), Haeckel postulated that evidence of human evolution would be found in theDutch East Indies (nowIndonesia). At that time, no remains of human ancestors had yet been identified. He described these theoretical remains in great detail and even named the as-yet unfound species,Pithecanthropus alalus, and instructed his students such asRichard andOskar Hertwig to go and find it.[citation needed]
One student did find some remains: a Dutchman namedEugène Dubois searched theEast Indies from 1887 to 1895, discovering the remains ofJava Man in 1891, consisting of a skullcap, thighbone, and a few teeth. These remains are among the oldest hominid remains ever found. Dubois classified Java Man with Haeckel'sPithecanthropus label, though they were later reclassified asHomo erectus. Some scientists of the day suggested[35] Dubois' Java Man as a potential intermediate form between modern humans and the common ancestor we share with the othergreat apes. The current consensus of anthropologists is that the direct ancestors of modern humans were African populations ofHomo erectus (possiblyHomo ergaster), rather than the Asian populations exemplified by Java Man andPeking Man. (Ironically, a new human species,Homo floresiensis, a dwarf human type, has recently been discovered in the island of Flores).[36]
Thecreationistpolygenism ofSamuel George Morton andLouis Agassiz, which presented humanraces as separately createdspecies, was rejected byCharles Darwin, who argued for themonogenesis of thehuman species and theAfrican origin of modern humans. Haeckel put forward a racist[37] doctrine of evolutionary polygenism based on the ideas of the linguistAugust Schleicher, in which several different language groups had arisen separately from speechless prehumanUrmenschen (German:proto-humans), which themselves had evolved from simian ancestors. These separate languages had completed the transition from animals to man, and under the influence of each main branch of languages, humans had evolved – in a kind ofLamarckian use-inheritance – as separate species, which could be subdivided into races. From this, Haeckel drew the implication that languages with the most potential yield the human races with the most potential, led by the Semitic and Indo-Germanic groups, with Berber, Jewish, Greco-Roman and Germanic varieties to the fore.[38] As Haeckel stated:[39]
We must mention here one of the most important results of the comparative study of languages, which for the Stammbaum of the species of men is of the highest significance, namely that human languages probably had a multiple or polyphyletic origin. Human language as such probably developed only after the species of speechlessUrmenschen orAffenmenschen (German:ape-men) had split into several species or kinds. With each of these human species, language developed on its own and independently of the others. At least this is the view of Schleicher, one of the foremost authorities on this subject. ... If one views the origin of the branches of language as the special and principal act of becoming human, and the species of humankind as distinguished according to their language stem, then one can say that the different species of men arose independently of one another.
Haeckel's view can be seen as a forerunner of the views ofCarleton Coon, who also believed that human races evolved independently and in parallel with each other. These ideas eventually fell from favour.[40]
Haeckel also applied the hypothesis of polygenism to the modern diversity of human groups. He became a key figure insocial darwinism and leading proponent ofscientific racism, stating for instance:[41]
The Caucasian, or Mediterranean man (Homo Mediterraneus), has from time immemorial been placed at the head of all the races of men, as the most highly developed and perfect. It is generally called the Caucasian race, but as, among all the varieties of the species, the Caucasian branch is the least important, we prefer the much more suitable appellation proposed byFriedrich Müller, namely, that ofMediterranese. For the most important varieties of this species, which are moreover the most eminent actors in what is called "Universal History", first rose to a flourishing condition on the shores of the Mediterranean. ... This species alone (with the exception of the Mongolian) has had an actual history; it alone has attained to that degree of civilisation which seems to raise men above the rest of nature.
Haeckel divided human beings into ten races, of which theCaucasian was the highest and the primitives were doomed to extinction.[42] In his view, 'Negroes' were savages and Whites were the most civilised: for instance, he claimed that '[t]he Negro' had stronger and more freely movable toes than any other race, which, he argued, was evidence of their being less evolved, and which led him to compare them to'"four-handed" Apes'.[43]
In hisOntogeny and Phylogeny Harvard paleontologistStephen Jay Gould wrote: "[Haeckel's] evolutionary racism; his call to the German people for racial purity and unflinching devotion to a 'just' state; his belief that harsh, inexorable laws of evolution ruled human civilization and nature alike, conferring upon favored races the right to dominate others ... all contributed to the rise ofNazism."[44]
In his introduction to theNazi Party ideologueAlfred Rosenberg's 1930 bookThe Myth of the Twentieth Century Peter Peel affirms that Rosenberg had indeed read Haeckel.[45]
In the same line of thought, historianDaniel Gasman states that Haeckel's ideology stimulated the birth ofFascist ideology in Italy and France.[46]
However, in 2009Robert J. Richards noted: "Haeckel, on his travels to Ceylon and Indonesia, often formed closer and more intimate relations with natives, even members of the untouchable classes, than with the European colonials." and says the Nazis rejected Haeckel, since he opposed antisemitism, while supporting ideas they disliked (for instance atheism, feminism, internationalism, pacifism etc.).[47]
Haeckel claimed the origin of humanity was to be found in Asia: he believed thatHindustan (Indian subcontinent) was the actual location where the first humans had evolved. Haeckel argued that humans were closely related to theprimates of Southeast Asia and rejected Darwin's hypothesis of Africa.[50][51]
Haeckel later claimed that themissing link was to be found on the lost continent ofLemuria located in the Indian Ocean. He believed that Lemuria was the home of the first humans and that Asia was the home of many of the earliestprimates; he thus supported that Asia was the cradle of hominid evolution. Haeckel also claimed that Lemuria connected Asia and Africa, which allowed themigration of humans to the rest of the world.[52][53]
In Haeckel's bookThe History of Creation (1884) he includedmigration routes which he thought the first humans had used outside of Lemuria.[54]
Illustrations of dog and human embryos, looking almost identical at 4 weeks then differing at 6 weeks, shown above a 6-week turtle embryo and 8-day hen embryo, presented by Haeckel in 1868 as convincing proof of evolution. The pictures of the earliest embryonic stages are now considered inaccurate.[55]
When Haeckel was a student in the 1850s he showed great interest inembryology, attending the rather unpopular lectures twice and in his notes sketched the visual aids: textbooks had few illustrations, and large format plates were used to show students how to see the tiny forms under a reflecting microscope, with the translucent tissues seen against a black background. Developmental series were used to show stages within a species, but inconsistent views and stages made it even more difficult to compare different species. It was agreed by all European evolutionists that allvertebrates looked very similar at an early stage, in what was thought of as a common ideal type, but there was a continuing debate from the 1820s between the Romanticrecapitulation theory that human embryos developed through stages of the forms of all the major groups of adult animals, literally manifesting a sequence of organisms on alinear chain of being, andKarl Ernst von Baer's opposing view, stated invon Baer's laws of embryology, that the early general forms diverged into four major groups of specialised forms without ever resembling the adult of another species, showing affinity to anarchetype but no relation to other types or anytransmutation of species. By the time Haeckel was teaching he was able to use a textbook with woodcut illustrations written by his own teacherAlbert von Kölliker, which purported to explain human development while also using other mammalian embryos to claim a coherent sequence. Despite the significance to ideas of transformism, this was not really polite enough for the new popular science writing, and was a matter for medical institutions and for experts who could make their own comparisons.[56]: 264–267 [57]
Darwin'sOn the Origin of Species, which made a powerful impression on Haeckel when he read it in 1864, was very cautious about the possibility of ever reconstructing the history of life, but did include a section reinterpreting von Baer's embryology and revolutionising the field of study, concluding that "Embryology rises greatly in interest, when we thus look at the embryo as a picture, more or less obscured, of the common parent-form of each great class of animals." It mentioned von Baer's 1828 anecdote (misattributing it toLouis Agassiz) that at an early stage embryos were so similar that it could be impossible to tell whether an unlabelled specimen was of a mammal, a bird, or of a reptile, and Darwin's own research using embryonic stages ofbarnacles to show that they arecrustaceans, while cautioning against the idea that one organism or embryonic stage is "higher" or "lower", or more or less evolved.[58] Haeckel disregarded such caution, and in a year wrote his massive and ambitiousGenerelle Morphologie, published in 1866, presenting a revolutionary new synthesis of Darwin's ideas with the German tradition ofNaturphilosophie going back toGoethe and with the progressive evolutionism ofLamarck in what he calledDarwinismus. He usedmorphology to reconstruct theevolutionary history of life, in the absence of fossil evidence using embryology as evidence of ancestral relationships. He invented new terms, includingontogeny andphylogeny, to present his evolutionised recapitulation theory that "ontogeny recapitulated phylogeny". The two massive volumes sold poorly, and were heavy going: with his limited understanding of German, Darwin found them impossible to read. Haeckel's publisher turned down a proposal for a "strictly scholarly and objective" second edition.[56]: 269–270
Haeckel's aim was a reformed morphology with evolution as the organising principle of a cosmic synthesis unifying science, religion, and art. He was giving successful "popular lectures" on his ideas to students and townspeople inJena, in an approach pioneered by his teacherRudolf Virchow. To meet his publisher's need for a popular work he used a student's transcript of his lectures as the basis of hisNatürliche Schöpfungsgeschichte of 1868, presenting a comprehensive presentation of evolution. In the Spring of that year he drew figures for the book, synthesising his views of specimens in Jena and published pictures to represent types. After publication he told a colleague that the images "are completely exact, partly copied from nature, partly assembled from all illustrations of these early stages that have hitherto become known". There were various styles ofembryological drawings at that time, ranging from more schematic representations to "naturalistic" illustrations of specific specimens. Haeckel believed privately that his figures were both exact and synthetic, and in public asserted that they were schematic like most figures used in teaching. The images were reworked to match in size and orientation, and though displaying Haeckel's own views of essential features, they support von Baer's concept that vertebrate embryos begin similarly and then diverge. Relating different images on a grid conveyed a powerful evolutionary message. As a book for the general public, it followed the common practice of not citing sources.[56]: 270–274
In 1868 Haeckel illustrated von Baer's observation that early embryos of different species could not be told apart by using the same woodcut three times as dog, chick and turtle embryos: he changed this in the next edition.
The book sold very well, and while some anatomical experts hostile to Haeckel's evolutionary views expressed some private concerns that certain figures had been drawn rather freely, the figures showed what they already knew about similarities in embryos. The first published concerns came fromLudwig Rütimeyer, a professor of zoology and comparative anatomy at theUniversity of Basel who had placed fossil mammals in an evolutionary lineage early in the 1860s and had been sent a complimentary copy. At the end of 1868 his review in theArchiv für Anthropologie wondered about the claim that the work was "popular and scholarly", doubting whether the second was true, and expressed horror about such public discussion of man's place in nature with illustrations such as the evolutionary trees being shown to non-experts. Though he made no suggestion that embryo illustrations should be directly based on specimens, to him the subject demanded the utmost "scrupulosity and conscientiousness" and an artist must "not arbitrarily model or generalise his originals for speculative purposes" which he considered proved by comparison with works by other authors. In particular, "one and the same, moreover incorrectly interpreted woodcut, is presented to the reader three times in a row and with three different captions as [the] embryo of the dog, the chick, [and] the turtle". He accused Haeckel of "playing fast and loose with the public and with science", and failing to live up to the obligation to the truth of every serious researcher. Haeckel responded with angry accusations of bowing to religious prejudice, but in the second (1870) edition changed the duplicated embryo images to a single image captioned "embryo of a mammal or bird". Duplication using galvanoplastic stereotypes (clichés) was a common technique in textbooks, but not on the same page to represent different eggs or embryos. In 1891 Haeckel made the excuse that this "extremely rash foolishness" had occurred in undue haste but was "bona fide", and since repetition of incidental details was obvious on close inspection, it is unlikely to have been intentional deception.[56]: 275–276, 282–286
The revised 1870 second edition of 1,500 copies attracted more attention, being quickly followed by further revised editions with larger print runs as the book became a prominent part of the optimistic, nationalist, anticlerical "culture of progress" inOtto von Bismarck's newGerman Empire. The similarity of early vertebrate embryos became common knowledge, and the illustrations were praised by experts such asMichael Foster of theUniversity of Cambridge. In the introduction to his 1871The Descent of Man, and Selection in Relation to Sex, Darwin gave particular praise to Haeckel, writing that ifNatürliche Schöpfungsgeschichte "had appeared before my essay had been written, I should probably never have completed it". The first chapter included an illustration: "As some of my readers may never have seen a drawing of an embryo, I have given one of man and another of a dog, at about the same early stage of development, carefully copied from two works of undoubted accuracy" with a footnote citing the sources and noting that "Häckel has also given analogous drawings in hisSchöpfungsgeschichte." The fifth edition of Haeckel's book appeared in 1874, with its frontispiece a heroic portrait of Haeckel himself, replacing the previous controversial image of the heads of apes and humans.[56]: 285–288 [59]
1874 illustration fromAnthropogenie showing "very early", "somewhat later" and "still later" stages of embryos of fish (F), salamander (A), turtle (T), chick (H), pig (S), cow (R), rabbit (K), and human (M)
Later in 1874, Haeckel's simplified embryology textbookAnthropogenie made the subject into a battleground over Darwinism aligned with Bismarck'sKulturkampf ("culture struggle") against the Catholic Church. Haeckel took particular care over the illustrations, changing to the leading zoological publisher Wilhelm Engelmann of Leipzig and obtaining from them use of illustrations from their other textbooks as well as preparing his own drawings including a dramatic double page illustration showing "early", "somewhat later" and "still later" stages of 8 different vertebrates. Though Haeckel's views had attracted continuing controversy, there had been little dispute about the embryos and he had many expert supporters, butWilhelm His revived the earlier criticisms and introduced new attacks on the 1874 illustrations.[60]
Expert anatomists were critical of Haeckel's work. Catholic priests also opposed Haeckel's views. Specifically, Haeckel's critics accused him of manipulating the embryo drawings to make the early stages of different species look more similar. They claimed that the drawings of four-week dog and human embryos had been copied without attribution from other sources, and changed by expanding dog's head and reducing the human head, moving the eye, and exaggerating the size of the human tail. Haeckel himself considered the drawings stylized and illustrative, but his detractors considered them forgery and fraud.[56]: 270–271, 288–296, 299
While it has been widely claimed that Haeckel was charged with fraud by five professors and convicted by a university court at Jena, there does not appear to be an independently verifiable source for this claim.[61] Recent analyses (Richardson 1998, Richardson and Keuck 2002) have found that some of the criticisms of Haeckel's embryo drawings were legitimate,[citation needed] but others were unfounded.[62][63] There were multiple versions of the embryo drawings, and Haeckel rejected the claims of fraud. It was later said that "there is evidence of sleight of hand" on both sides of the feud between Haeckel andWilhelm His.[64]Robert J. Richards, in a paper published in 2008, defends the case for Haeckel, shedding doubt against the fraud accusations based on the material used for comparison with what Haeckel could access at the time.[65]
Some historians have seen Haeckel's social Darwinism as a forerunner toNazi ideology.[66][67][68][page needed] Others have denied the relationship altogether.[69][70][71]
The evidence is in some respects ambiguous. On one hand, Haeckel was an advocate ofscientific racism. He held that evolutionary biology had definitively proven that races were unequal in intelligence and ability, and that their lives were also of unequal value, e.g., "These lower races (such as the Veddahs or Australian negroes) are psychologically nearer to the mammals (apes or dogs) than to civilised Europeans; we must therefore, assign a totally different value to their lives."[72] As a result of the "struggle for existence", it followed that the "lower" races would eventually be exterminated.[73] He was also a social Darwinist who believed that "survival of the fittest" was a natural law, and that struggle led to improvement of the race.[74] As an advocate of eugenics, he also believed that about 200,000mentally andcongenitally ill should be killed by a medical control board.[75] This idea was later put into practice byNazi Germany, as part of theAktion T4 program.[76]
Alfred Ploetz, founder of theGerman Society for Racial Hygiene, praised Haeckel repeatedly, and invited him to become an honorary member. Haeckel accepted the invitation.[77] Haeckel also believed that Germany should be governed by an authoritarian political system, and that inequalities both within and between societies were an inevitable product of evolutionary law.[78] Haeckel was also an extreme German nationalist who believed strongly in the superiority of German culture.[79]
On the other hand, Haeckel was not an anti-Semite. In the racial hierarchies he constructed Jews tended to appear closer to the top, rather than closer to the bottom as inNazi racial thought.[80] He was also a pacifist until the First World War, when he wrote propaganda in favor of the war.[81] The principal arguments of historians who deny a meaningful connection between Haeckel and Nazism are that Haeckel's ideas were very common at the time, that Nazis were much more strongly influenced by other thinkers, and that Haeckel is properly classified as a 19th-century German liberal, rather than a forerunner to Nazism.[82][83] They also point to incompatibilities between evolutionary biology and Nazi ideology.[84]
Nazis themselves divided on the question of whether Haeckel should be counted as a pioneer of their ideology.SS captain and biologistHeinz Brücher wrote a biography of Haeckel in 1936, in which he praised Haeckel as a "pioneer in biological state thinking".[85] This opinion was also shared by the scholarly journal,Der Biologe, which celebrated Haeckel's 100th birthday, in 1934, with several essays acclaiming him as a pioneering thinker of Nazism.[86] Other Nazis kept their distance from Haeckel. Nazi propaganda guidelines issued in 1935 listed books which popularized Darwin and evolution on an "expunged list". Haeckel was included by name as a forbidden author.[87] Gunther Hecht, a member of the Nazi Department of Race Politics, also issued a memorandum rejecting Haeckel as a forerunner of Nazism.[88] Kurt Hildebrandt, a Nazi political philosopher, also rejected Haeckel.[88] Eventually Haeckel was rejected by Nazi bureaucrats.[89]
In Jena he is remembered with a monument at Herrenberg (erected in 1969),[94] an exhibition atErnst-Haeckel-Haus,[95] and at theJena Phyletic Museum, which continues to teach about evolution and share his work to this day.[96]
The research vesselErnst Haeckel is named in his honor.[98]
In 1981, a botanical journal calledErnstia was started being published in the city ofMaracay, Venezuela.[99]
In 2013,Ernstia, agenus ofcalcareous sponges in the familyClathrinidae. The genus was erected to contain five species previously assigned toClathrina. The genus name honors Ernst Haeckel for his contributions towards sponge taxonomy and phylogeny.[100][101]
Darwin's 1859 bookOn the Origin of Species had immense popular influence, but although its sales exceeded its publisher's hopes it was a technical book rather than a work of popular science: long, difficult and with few illustrations. One of Haeckel's books did a great deal to explain his version of "Darwinism" to the world. It was a bestselling, provocatively illustrated book in German, titledNatürliche Schöpfungsgeschichte, published in Berlin in 1868, and translated into English asThe History of Creation in 1876. Until 1909, eleven editions had appeared, as well as 25 translations into other languages. TheNatürliche Schöpfungsgeschichte cemented Haeckel's reputation as one of Germany's most forceful popularizers of science. HisWelträthsel were reprinted ten times after the book's first publication in 1899; ultimately, over 400,000 copies were sold.[102]
Haeckel argued that human evolution consisted of precisely 22 phases, the 21st – the "missing link" – being a halfway step between apes and humans. He even formally named this missing linkPithecanthropus alalus, translated as "ape man without speech".[103]
Haeckel's literary output was extensive, including many books, scientific papers, and illustrations.[104]
"Monophyletischer Stammbaum der Organismen" fromGenerelle Morphologie der Organismen (1866) with the three branches Plantae, Protista, Animalia
Generelle Morphologie der Organismen: allgemeine Grundzüge der organischen Formen-Wissenschaft, mechanisch begründet durch die von Charles Darwin reformirte Descendenz-Theorie. (1866) Berlin (General morphology of organisms: general foundations of form-science, mechanically grounded by the descendance theory reformed by Charles Darwin)
Über unsere gegenwärtige Kenntnis vom Ursprung des Menschen (1898) (On our current understanding of the origin of man) – in EnglishThe Last Link, 1898
Der Kampf um den Entwickelungsgedanken (1905) (The struggle over thought on evolution) – in EnglishLast Words on Evolution: A Popular Retrospect and Summary, Translated from the Second Edition by Joseph McCabe, New York: Peter Eckler, Publisher; London: A. Owen & Co., 1906.
^Haeckel, Ernst (1866).Generelle Morphologie der Organismen [The General Morphology of Organisms] (in German). Vol. 2. Berlin, (Germany): Georg Reimer. From p. 286:"Unter Oecologie verstehen wir die gesammte Wissenschaft von den Beziehungen des Organismus zur umgebenden Aussenwelt, wohin wir im weiteren Sinne alle "Existenz-Bedingungen" rechnen können." (By "ecology" we understand the comprehensive science of the relationships of the organism to its surrounding environment, where we can include, in the broader sense, all "conditions of existence".)
^Haeckel, Ernst (1866).Generelle Morphologie der Organismen [The General Morphology of Organisms] (in German). Vol. 1. Berlin, (Germany): G. Reimer. pp. 28–29. Haeckel noted that species constantly evolved into new species that seemed to retain few consistent features among themselves and therefore few features that distinguished them as a group ("a self-contained unity")."Wohl aber ist eine solche reale und vollkommen abgeschlossene Einheit die Summe aller Species, welche aus einer und derselben gemeinschaftlichen Stammform allmählig sich entwickelt haben, wie z. B. alle Wirbelthiere. Diese Summe nennen wir Stamm (Phylon)." (However, perhaps such a real and completely self-contained unity is the aggregate of all species which have gradually evolved from one and the same common original form, as, for example, all vertebrates. We name this aggregate [a]Stamm [i.e., race] (Phylon).)
^(Haeckel, 1866),vol. 1, p. 29:"Die Untersuchung der Entwicklung dieser Stämme und die Feststellung der genealogischen Verwandtschaft aller Species, die zu einem Stamm gehören, halten wir für die höchste und letzte besondere Aufgabe der organischen Morphologie. Im sechsten Buche werden wir die Grundzüge dieser Phylogenie oder Entwicklungsgeschichte der organischen Stämme (Kreise oder "Typen") festzustellen haben." (The investigation of the evolution of these phyla and the identification of the genealogical kinship of all species that belong to a phylum—we deem [this] the highest and ultimately specific task of organic morphology. In the sixth book, we will have to establish the outline of this "phylogeny" or history of the evolution of the organic phyla (groups or "types").)
^(Haeckel, 1866), vol. 1, pp. 215 ff. From p. 215:"VII. Character des Protistenreiches." (VII. Character of the kingdom of Protists.) From p. 216:"VII. B. Morphologischer Character des Protistenreiches. Ba. Character der protistischen Individualitäten. Der wesentliche tectologische Character der Protisten liegt in der sehr unvollkommenen Ausbildung und Differenzirung der Individualität überhaupt, insbesondere aber derjenigen zweiter Ordnung, der Organe. Sehr viele Protisten erheben sich niemals über den morphologischen Werth von Individuen erster Ordnung oder Plastiden." (VII. B. Morphological character of the kingdom of protists. Ba. Character of the protist Individualities. The essentialtectological character of protists lies in the very incomplete formation and differentiation of individuality generally, however particularly of those of the second order, the organs. Very many protists never rise above the morphological level of individuals of the first order or plastids.)
^Freedom in Science and Teaching. German 1877, English 1879,ISBN1-4102-1175-4.
^Hawkins, Mike (1997).Social Darwinism in European and American Thought. Cambridge: Cambridge University Press. p. 140.
^Hawkins, Mike (1997).Social Darwinism in European and American Thought. Cambridge: Cambridge University Press. p. 137.
^Di Gregorio, Mario A. (2005). "1: Young Haeckel".From Here to Eternity: Ernst Haeckel and Scientific Faith. Religion, Theologie Und Naturwissenschaft/Religion, Theology, And Natural Science. Vol. 3. Goettingen: Vandenhoeck & Ruprecht. p. 26.ISBN9783525569726. Retrieved25 March 2019.On 16 February 1834 a son was born to Charlotte and Carl Gottlob Haeckel in Kanal 24a (later Yorkstrasse 7), Potsdam, Prussia. His name was Ernst Heinrich Phillip August, and he was destined to become one of the most influential and controversial thinkers of his time.
^abcdefghi"Ernst Haeckel" (article),German Wikipedia, 26 October 2006, webpage:DE-Wiki-Ernst-Haeckel: last paragraph of "Leben" (Life) section.
^New York Times Haeckel Again Honored in Spite of Himself on his 80th Birthday, published: 22 February 1914
^Felden, Emil[in German] (1914)."Felden Pastor an St. Martini Bremen" [Pastor of St. Martini Church, Bremen, Germany]. InSchmidt, Heinrich (ed.).Was wir Ernst Haeckel Verdanken (What We Owe to Ernst Haeckel): Ein Buch der Verehrung und Dankbarkeit (in German). Vol. 2. Deutscher Monistenbund. Leipzig: Verlag Unesma. pp. 125–128.testimony of Emil Felden inWas wir Ernst Haeckel Verdanken, vol. ii, p. 125.
^Carus, Paul (1914).The Open Court. Open Court Publishing Company. p. 385.PROFESSOR Ernst Haeckel's celebration of his 80th birthday, ...on this occasion we note a work of two stately volumes, entitledWas wir Ernst Haeckel verdanken, edited at the request of the GermanMonistenbund by Heinrich Schmidt of Jena. (Image of p. 385 at Google Books)
^Innes, Shelley (2006). "From Here to Eternity: Ernst Haeckel and Scientific Faith, Religion, Theology, and Natural Science, Vol. 3 by Mario di Gregorio".Journal of the History of Biology.39 (1):214–216.doi:10.1007/s10739-006-0001-9.JSTOR4332000.S2CID189843968.
^Weir, Todd H.Secularism and religion in nineteenth-century Germany. The rise of the fourth confession. Cambridge University Press, 2014, p. 67
^Daum, Andreas W. (1998).Wissenschaftspopularisierung im 19. Jahrhundert: Bürgerliche Kultur, naturwissenschaftliche Bildung und die deutsche Öffentlichkeit, 1848–1914. Munich: Oldenbourg. pp. 215–219.ISBN3-486-56337-8.
^Health, Race and German Politics Between National Unification and Nazism byPaul Weindling, Cambridge University Press, 1993., pp. 46, 250
^Richardson and Keuck, (Biol. Review (2002), 77, pp. 495–528) show that it is a simplification to suppose that Haeckel held the recapitulation theory in its strong form. They quote Haeckel as saying "If [recapitulation] was always complete, it would be a very easy task to construct whole phylogeny on the basis of ontogeny. … There is certainly, even now, a number of lower vertebrate animals (e.g. some Anthozoa and Vermes) where we are authorised to interpret each embryological form directly as the historical representation or portrait-like silhouette of an extinct ancestral form. But in a great majority of animals, including man, this is not possible because the infinitely varied conditions of existence have led the embryonic forms themselves to be changed and to partly lose their original condition (Haeckel, 1903: pp. 435–436)"
^Horder, Tim (April 2006). "Heterochrony".Encyclopedia of Life Sciences. John Wiley & Sons.
^Hall, B. K. (2003). "Evo-Devo: evolutionary developmental mechanisms".International Journal of Developmental Biology.47 (7–8):491–495.PMID14756324.
^Natürliche Schöpfungsgeschichte (1868), p. 511; quoted afterRobert J. Richards, "The linguistic creation of man: Charles Darwin, August Schleicher, Ernst Haeckel, and the Missing Link in Nineteenth-Century Evolutionary Theory".[1]Archived 3 February 2004 at theWayback Machine
^Daniel Gasman (1998). "Haeckel's Monism and the Birth of Fascist Ideology".Studies in Modern European History 33. Peter Lang Pub Incorporated.ISSN0893-6897.ISBN978-0-8204-4108-5
^Robert J. Richards, "Myth 19: That Darwin and Haeckel Were Complicit in Nazi Biology", inRonald L. Numbers, ed.,Galileo Goes to Jail and Other Myths About Science and Religion, Harvard University Press, 2009, p. 174.
^Max Planck Institute of Geoanthropology (10 September 2019)."Jenaer Erklärung".www.shh.mpg.de. Retrieved17 November 2023.
^Nachrichten Informationsdienst Wissenschaft (10 September 2019)."'Human races' do not exist".nachrichten.idw-online.de (in German). Retrieved17 November 2023.
^Douglas Palmer,Prehistoric past: The four billion year history of life on earth, p. 43
^Brian Regal,Human evolution: a guide to the debates, pp. 73–75
^Christopher J Norton and David R Braun.Asian Paleoanthropology: From Africa to China and beyond. p. 4
^Mario A. Di Gregorio.From here to Eternity: Ernst Haeckel and the scientific faith. p. 480
^Michael K. Richardson. 1998. "Haeckel's embryos continued".Science 281:1289, quoted in NaturalScience.com webpageRe:Ontogeny and phylogenyArchived 14 November 2006 at theWayback Machine: A Letter from Richard Bassetti; Editor's note.
^"While some criticisms of the drawings are legitimate, others are more tendentious", Richardson and Keuck "Haeckel's ABC of evolution and development",Biol. Rev. (2002),77, pp. 495–528. Quoted from p. 495.
^Richardson & Keuck 2001. See for example, their Fig. 7, showing His's drawing of the forelimb of a deer embryo developing a clef, compared with a similar drawing (Sakurai, 1906) showing the forelimb initially developing as a digital plate with rays. Richardson and Keuck say "Unfortunately His's embryos are mostly at later stages than the nearly identical early stage embryos illustrated by Haeckel [top row of Haeckel's drawing]. Thus they do not inform the debate and may themselves be disingenuous." p. 518.
^Gasman, Daniel (1971).The Scientific Origins of National Socialism: Social Darwinism in Ernst Haeckel and the German Monist League. New Brunswick: MacDonald & co. p. xiv.
^Weikart, Richard (2004).From Darwin to Hitler. New York: Palgrave MacMillan.ISBN1403965021.
^The Story of Mount Cook National Park : a handbook to help you enjoy the park (6th ed.). New Zealand: Dept. of Lands and Survey; Auckland, N.Z. 1986. p. 152.ISBN9780477061360.
