Editing Orthogenesis (section)

==Status==

===In science===
[[File:Human pedigree.jpg|thumb|left|upright=0.9<!--img is almost square, equalizing area-->|A satirical opinion of [[Ernst Haeckel]]'s 1874 ''The modern theory of the descent of man'', showing a linear sequence of forms leading up to 'Man'. Illustration by G. Avery for ''[[Scientific American]]'', 11 March 1876]]

The stronger versions of the orthogenetic hypothesis began to lose popularity when it became clear that they were inconsistent with the patterns found by [[paleontology|paleontologists]] in the [[fossil record]], which were non-rectilinear (richly branching) with many complications. The hypothesis was abandoned by mainstream biologists when no mechanism could be found that would account for the process, and the theory of evolution by natural selection came to prevail.<ref name=Mayr1982>{{cite book |last=Mayr |first=Ernst |author-link=Ernst Mayr |date=1982 |title=The Growth of Biological Thought: Diversity, Evolution, and Inheritance |publisher=Harvard University Press |pages=530–531 |isbn=978-0-674-36446-2}}</ref> The historian of biology Edward J. Larson commented that

{{quote|At theoretical and philosophical levels, Lamarckism and orthogenesis seemed to solve too many problems to be dismissed out of hand—yet biologists could never reliably document them happening in nature or in the laboratory. Support for both concepts evaporated rapidly once a plausible alternative appeared on the scene.{{sfn|Larson|2004|page=127}}}}

The [[Modern synthesis (20th century)|modern synthesis]] of the 1930s and 1940s, in which the [[genetics|genetic]] mechanisms of evolution were incorporated, appeared to refute the hypothesis for good. As more was understood about these mechanisms it came to be held that there was no naturalistic way in which the newly discovered mechanism of [[heredity]] could be far-sighted or have a memory of past trends. Orthogenesis was seen to lie outside the [[methodological naturalism]] of the sciences.<ref>{{cite book |author-link=Stephen Jay Gould |last=Gould |first=Stephen Jay |title=The Structure of Evolutionary Theory |date=2002 |pages=[https://archive.org/details/structureofevolu00goul/page/ Chapter 7, section "Synthesis as Restriction"] |isbn=978-0-674-00613-3 |title-link=The Structure of Evolutionary Theory }}</ref><ref>{{cite book |last=Levinton |first=Jeffrey S. |date=2001 |title=Genetics, Paleontology, and Macroevolution |publisher=Cambridge University Press |pages=14–16 |isbn=978-0-521-80317-5}}</ref><ref>{{cite book |last1=Montgomery |first1=Georgina M. |last2=Largent |first2=Mark A. |date=2015 |title=A Companion to the History of American Science  |publisher=Wiley |page=218 |isbn=978-1-4051-5625-7 |quote=With the integration of Mendelian genetics and population genetics into evolutionary theory in the 1930s a new generation of biologists applied mathematical techniques to investigate how changes in the frequency of genes in populations combined with natural selection could produce species change. This demonstrated that Darwinian natural selection was the primary mechanism for evolution and that other models of evolution, such as neo-Lamarckism and orthogenesis, were invalid.}}</ref>

[[File:Ernst Mayr PLoS.jpg|thumb|[[Ernst Mayr]] considered orthogenesis effectively taboo in 1948.{{sfn|Ruse|1996|page=447}}]]

By 1948, the evolutionary biologist [[Ernst Mayr]], as editor of the journal ''Evolution'', made the use of the term ''orthogenesis'' taboo: "It might be well to abstain from use of the word 'orthogenesis' .. since so many of the geneticists seem to be of the opinion that the use of the term implies some supernatural force."{{sfn|Ruse|1996|page=447}}<ref name=Mayr1948/> For these and other reasons, belief in evolutionary progress has remained "a persistent [[heresy]]",<ref name=Popov2005>{{cite web |last1=Popov |first1=Igor |title=The Persistence of Heresy: The Concepts of Directed Evolution (Orthogenesis) |url=http://www.kli.ac.at/events/event-detail/1112872500/the-persistence-of-heresy-the-concepts-of-directed-evolution-orthogenesis |access-date=15 April 2017 |date=7 April 2005 |archive-date=15 April 2017 |archive-url=https://web.archive.org/web/20170415202806/http://www.kli.ac.at/events/event-detail/1112872500/the-persistence-of-heresy-the-concepts-of-directed-evolution-orthogenesis |url-status=dead }}</ref> among evolutionary biologists including [[E. O. Wilson]]<ref name=Ruse>{{cite web |last1=Ruse |first1=Michael |author-link1=Michael Ruse |title=Edward O. Wilson on Sociobiology |url=http://www.chronicle.com/blogs/brainstorm/edward-o-wilson-on-sociobiology/22185 |publisher=The Chronicle of Higher Education |access-date=4 April 2017 |date=31 March 2010}}</ref> and [[Simon Conway Morris]], although often denied or veiled. The philosopher of biology [[Michael Ruse]] wrote that "some of the most significant of today's evolutionists are progressionists, and that because of this we find (absolute) progressionism alive and well in their work."{{sfn|Ruse|1996|p=536}} He argued that progressionism has harmed the status of [[evolutionary biology]] as a mature, professional science.{{sfn|Ruse|1996|p=530}} Presentations of evolution remain characteristically progressionist, with humans at the top of the "Tower of Time" in the [[Smithsonian Institution]] in [[Washington D.C.]], while ''[[Scientific American]]'' magazine could illustrate the history of life leading progressively from mammals to dinosaurs to primates and finally man. Ruse noted that at the popular level, progress and evolution are simply synonyms, as they were in the nineteenth century, though confidence in the value of cultural and technological progress has declined.{{sfn|Ruse|1996|pages=526–539}}

The discipline of [[evolutionary developmental biology]], however, is open to an expanded concept of heredity that incorporates the physics of [[self-organization]]. With its rise in the late 20th-early 21st centuries, ideas of constraint and preferred directions of morphological change have made a reappearance in evolutionary theory.<ref>see, for example, {{cite book |editor1-link=Gerd Müller (theoretical biologist)|editor1=Müller, Gerd B.|editor2-link=Stuart Newman|editor2=Newman, Stuart A.|title=Origination of Organismal Form |date=2003 |publisher=Bradford |isbn=978-0-262-13419-4|title-link=Origination of Organismal Form}}</ref>

===In popular culture===
[[File:Huxley - Mans Place in Nature.jpg|thumb|left|upright=1.3|The frontispiece to [[Thomas Henry Huxley]]'s 1863 ''[[Evidence as to Man's Place in Nature]]'' was intended to compare the skeletons of apes and humans, but unintentionally created a durable [[meme]] of supposed "monkey-to-man" progress.<ref name="Tucker2012">{{cite news|last1=Tucker|first1=Jennifer|title=What our most famous evolutionary cartoon gets wrong|url=https://www.bostonglobe.com/ideas/2012/10/27/what-our-most-famous-evolutionary-cartoon-gets-wrong/drKMD5121W6EUxXJ4pF0YL/story.html|access-date=29 December 2017|work=The [[Boston Globe]]|date=28 October 2012}}</ref>]]
{{further|March of Progress}}

In popular culture, progressionist images of evolution are widespread. The historian Jennifer Tucker, writing in ''[[The Boston Globe]]'', notes that [[Thomas Henry Huxley]]'s 1863 illustration comparing the skeletons of apes and humans "has become an iconic and instantly recognizable visual shorthand for evolution."<ref name="Tucker2012"/> She calls its history extraordinary, saying that it is "one of the most intriguing, and most misleading, drawings in the modern history of science." Nobody, Tucker observes, supposes that the "monkey-to-man" sequence accurately depicts Darwinian evolution. ''The Origin of Species'' had only one illustration, a diagram showing that random events create a process of branching evolution, a view that Tucker notes is broadly acceptable to modern biologists. But Huxley's image recalled the great chain of being, implying with the force of a visual image a "logical, evenly paced progression" leading up to ''Homo sapiens'', a view denounced by [[Stephen Jay Gould]] in ''[[Wonderful Life (book)|Wonderful Life]]''.<ref name="Tucker2012"/>

[[File:Man is But a Worm.jpg|thumb|upright|''Man is But a Worm'' by [[Edward Linley Sambourne]], ''Punch's Almanack'' for 1882]]

Popular perception, however, had seized upon the idea of linear progress. [[Edward Linley Sambourne]]'s ''Man is But a Worm'', drawn for ''Punch's Almanack'', mocked the idea of any evolutionary link between humans and animals, with a sequence from chaos to earthworm to apes, primitive men, a Victorian beau, and Darwin in a pose that according to Tucker recalls [[Michelangelo]]'s figure of [[Adam]] in his fresco adorning the ceiling of the [[Sistine Chapel]]. This was followed by a flood of variations on the evolution-as-progress theme, including ''The New Yorker''{{'}}s 1925 "The Rise and Fall of Man", the sequence running from a chimpanzee to [[Neanderthal man]], [[Socrates]], and finally the lawyer [[William Jennings Bryan]] who argued for the anti-evolutionist prosecution in the [[Scopes Trial]] on the State of Tennessee law limiting the teaching of evolution.  Tucker noted that [[Rudolph Franz Zallinger]]'s 1965 "[[March of Progress|The Road to Homo Sapiens]]" fold-out illustration in [[F. Clark Howell]]'s ''Early Man'', showing a sequence of 14 walking figures ending with modern man, fitted the palaeoanthropological discoveries "not into a branching Darwinian scheme, but into the framework of the original Huxley diagram." Howell ruefully commented that the "powerful and emotional" graphic had overwhelmed his Darwinian text.<ref name="Tucker2012"/>

[[File:Astronomy Evolution 2 (27458655072).jpg|thumb|One of many versions of the progressionist [[meme]]: ''Astronomy Evolution 2'' artwork by Giuseppe Donatiello, 2016]]

===Sliding between meanings===

Scientists, Ruse argues, continue to slide easily from one notion of progress to another: even committed Darwinians like [[Richard Dawkins]] embed the idea of cultural progress in a theory of cultural units, [[meme]]s, that act much like genes.{{sfn|Ruse|1996|pages=526–539}} Dawkins can speak of "progressive rather than random&nbsp;... trends in evolution".<ref>{{cite journal |author1=Dawkins, Richard |author2=Krebs, J. R. |author-link1=Richard Dawkins |author-link2=John Krebs, Baron Krebs |title=Arms races between and within species |date=1979 |journal=Proceedings of the Royal Society B |volume=205 |issue=1161 |pages=489–511 |doi=10.1098/rspb.1979.0081|pmid=42057 |bibcode=1979RSPSB.205..489D |s2cid=9695900 }}</ref>{{sfn|Ruse|1996|page=466}} Dawkins and [[John Krebs, Baron Krebs|John Krebs]] deny the "earlier [Darwinian] prejudice"{{sfn|Ruse|1996|page=468}} that there is anything "inherently progressive about evolution",{{sfn|Dawkins|1986|page=178}}{{sfn|Ruse|1996|page=468}} but, Ruse argues, the feeling of progress comes from evolutionary [[arms race]]s which remain in Dawkins's words "by far the most satisfactory explanation for the existence of the advanced and complex machinery that animals and plants possess".{{sfn|Dawkins|1986|page=181}}{{sfn|Ruse|1996|page=468}}

Ruse concludes his detailed analysis of the idea of ''Progress'', meaning a progressionist philosophy, in evolutionary biology by stating that evolutionary thought came out of that philosophy. Before Darwin, Ruse argues, evolution was just a [[pseudoscience]]; Darwin made it respectable, but "only as popular science". "There it remained frozen, for nearly another hundred years",{{sfn|Ruse|1996|pages=526–539}} until mathematicians such as Fisher{{sfn|Ruse|1996|pages=292–295}} provided "both [[population genetics|models]] and status", enabling evolutionary biologists to construct the [[Modern synthesis (20th century)|modern synthesis]] of the 1930s and 1940s. That made biology a professional science, at the price of ejecting the notion of progress. That, Ruse argues, was a significant cost to "people [biologists] still firmly committed to Progress" as a philosophy.{{sfn|Ruse|1996|pages=526–539}}