![Lamarck's Two-Factor Theory](https://upload.wikimedia.org/wikipedia/commons/2/22/Lamarck%27s_Two-Factor_Theory.svg)
Orthogenesis, also known as orthogenetic evolution, progressive evolution, evolutionary progress, or progressionism, is an
obsolete biological
hypothesis
A hypothesis (plural hypotheses) is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it. Scientists generally base scientific hypotheses on previous obse ...
that
organism
In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and ...
s have an innate tendency to
evolve in a definite direction
towards some goal (teleology) due to some internal mechanism or "driving force". According to the theory, the
largest-scale trends in evolution have an absolute goal such as
increasing biological complexity. Prominent historical figures who have championed some form of evolutionary progress include
Jean-Baptiste Lamarck
Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (1 August 1744 – 18 December 1829), often known simply as Lamarck (; ), was a French naturalist, biologist, academic, and soldier. He was an early proponent of the idea that biologi ...
,
Pierre Teilhard de Chardin
Pierre Teilhard de Chardin ( (); 1 May 1881 – 10 April 1955) was a French Jesuit priest, scientist, paleontologist, theologian, philosopher and teacher. He was Darwinian in outlook and the author of several influential theological and philos ...
, and
Henri Bergson
Henri-Louis Bergson (; 18 October 1859 – 4 January 1941) was a French philosopherHenri Bergson. 2014. Encyclopædia Britannica Online. Retrieved 13 August 2014, from https://www.britannica.com/EBchecked/topic/61856/Henri-Bergson .
The term ''orthogenesis'' was introduced by
Wilhelm Haacke
Johann Wilhelm Haacke (23 August 1855 – 6 December 1912) was a German zoologist born in Clenze, Lower Saxony, who served as Director of the South Australian Museum in Adelaide from 1882 to 1884.
Career
He studied zoology at the University ...
in 1893 and popularized by
Theodor Eimer
Gustav Heinrich Theodor Eimer (22 February 1843 – 29 May 1898) was a German zoologist. He was a popularizer of orthogenesis, a form of directed evolution through mutations that made use of Lamarckian principles.
Life and work
Eimer was born ...
five years later. Proponents of orthogenesis had rejected the theory of
natural selection
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. Charle ...
as the organizing mechanism in
evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
for a rectilinear model of directed evolution. With the emergence of the
modern synthesis
Modern synthesis or modern evolutionary synthesis refers to several perspectives on evolutionary biology, namely:
* Modern synthesis (20th century), the term coined by Julian Huxley in 1942 to denote the synthesis between Mendelian genetics and s ...
, in which
genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar wor ...
was integrated with evolution, orthogenesis and other
alternatives to Darwinism
Alternatives to Darwinian evolution have been proposed by scholars investigating biology to explain signs of evolution and the relatedness of different groups of living things. The alternatives in question do not deny that evolutionary changes ove ...
were largely abandoned by biologists, but the notion that evolution represents progress is still widely shared; modern supporters include
E. O. Wilson
Edward Osborne Wilson (June 10, 1929 – December 26, 2021) was an American biologist, naturalist, entomologist and writer. According to David Attenborough, Wilson was the world's leading expert in his specialty of myrmecology, the study of an ...
and
Simon Conway Morris
Simon Conway Morris (born 1951) is an English palaeontologist, evolutionary biologist, and astrobiologist known for his study of the fossils of the Burgess Shale and the Cambrian explosion. The results of these discoveries were celebrated in ...
. The evolutionary biologist
Ernst Mayr
Ernst Walter Mayr (; 5 July 1904 – 3 February 2005) was one of the 20th century's leading evolutionary biologists. He was also a renowned Taxonomy (biology), taxonomist, tropical explorer, ornithologist, Philosophy of biology, philosopher o ...
made the term effectively taboo in the journal ''
Nature
Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...
'' in 1948, by stating that it implied "some supernatural force".
[Letter from ]Ernst Mayr
Ernst Walter Mayr (; 5 July 1904 – 3 February 2005) was one of the 20th century's leading evolutionary biologists. He was also a renowned Taxonomy (biology), taxonomist, tropical explorer, ornithologist, Philosophy of biology, philosopher o ...
to R. H. Flower, ''Evolution'' papers, 23 January 1948 The American paleontologist
George Gaylord Simpson
George Gaylord Simpson (June 16, 1902 – October 6, 1984) was an American paleontologist. Simpson was perhaps the most influential paleontologist of the twentieth century, and a major participant in the Modern synthesis (20th century), modern ...
(1953) attacked orthogenesis, linking it with
vitalism
Vitalism is a belief that starts from the premise that "living organisms are fundamentally different from non-living entities because they contain some non-physical element or are governed by different principles than are inanimate things." Wher ...
by describing it as "the mysterious inner force". Despite this, many museum displays and textbook illustrations continue to give the impression that evolution is directed.
The philosopher of biology
Michael Ruse
Michael Ruse (born 21 June 1940) is a British-born Canadian philosopher of science who specializes in the philosophy of biology and works on the relationship between science and religion, the creation–evolution controversy, and the demarcatio ...
notes that in popular culture, evolution and progress are synonyms, while the unintentionally misleading image of the ''
March of Progress
''The March of Progress'', originally titled ''The Road to Homo Sapiens'', is an illustration that presents 25 million years of human evolution. It was created for the ''Early Man'' volume of the ''Life Nature Library'', published in 1965, and dr ...
'', from apes to modern humans, has been widely imitated.
Definition
![Theodor Eimer (Professorengalerie Universität Tübingen)](https://upload.wikimedia.org/wikipedia/commons/b/bd/Theodor_Eimer_%28Professorengalerie_Universit%C3%A4t_T%C3%BCbingen%29.jpg)
The term orthogenesis (from Ancient el, ὀρθός orthós, "straight", and Ancient el, γένεσις génesis, "origin") was first used by the biologist
Wilhelm Haacke
Johann Wilhelm Haacke (23 August 1855 – 6 December 1912) was a German zoologist born in Clenze, Lower Saxony, who served as Director of the South Australian Museum in Adelaide from 1882 to 1884.
Career
He studied zoology at the University ...
in 1893.
Theodor Eimer
Gustav Heinrich Theodor Eimer (22 February 1843 – 29 May 1898) was a German zoologist. He was a popularizer of orthogenesis, a form of directed evolution through mutations that made use of Lamarckian principles.
Life and work
Eimer was born ...
was the first to give the word a definition; he defined orthogenesis as "the general law according to which evolutionary development takes place in a noticeable direction, above all in specialized groups".
In 1922, the zoologist Michael F. Guyer
Michael Frederic Guyer (1874–1959) was an American cytologist and zoologist.
Guyer was professor of zoology at the University of Wisconsin. In 1902, he independently discovered Mendel's laws from the cytology of spermatogenesis in pigeon h ...
wrote:
According to Susan R. Schrepfer in 1983:
In 1988, Francisco J. Ayala
Francisco José Ayala Pereda (born March 12, 1934) is a Spanish-American evolutionary biologist, philosopher, and former Catholic priest who was a longtime faculty member at the University of California, Irvine and University of California, Dav ...
defined progress as "systematic change in a feature belonging to all the members of a sequence in such a way that posterior members of the sequence exhibit an improvement of that feature". He argued that there are two elements in this definition, directional change and improvement according to some standard. Whether a directional change constitutes an improvement is not a scientific question; therefore Ayala suggested that science should focus on the question of whether there is directional change, without regard to whether the change is "improvement". This may be compared to Stephen Jay Gould
Stephen Jay Gould (; September 10, 1941 – May 20, 2002) was an American paleontologist, evolutionary biologist, and historian of science. He was one of the most influential and widely read authors of popular science of his generation. Gould sp ...
's suggestion of "replacing the idea of progress with an operational notion of directionality".
In 1989, Peter J. Bowler
Peter J. Bowler (born 8 October 1944) is a historian of biology who has written extensively on the history of evolutionary thought, the history of the environmental sciences, and on the history of genetics. His 1984 book, ''Evolution: The His ...
defined orthogenesis as:
In 1996, Michael Ruse
Michael Ruse (born 21 June 1940) is a British-born Canadian philosopher of science who specializes in the philosophy of biology and works on the relationship between science and religion, the creation–evolution controversy, and the demarcatio ...
defined orthogenesis as "the view that evolution has a kind of momentum of its own that carries organisms along certain tracks".
History
Medieval
The possibility of progress is embedded in the mediaeval great chain of being
The great chain of being is a hierarchical structure of all matter and life, thought by medieval Christianity to have been decreed by God. The chain begins with God and descends through angels, humans, animals and plants to minerals.
The great ...
, with a linear sequence of forms from lowest to highest. The concept, indeed, had its roots in Aristotle's biology
Aristotle's biology is the theory of biology, grounded in systematic observation and collection of data, mainly zoological, embodied in Aristotle's books on the science. Many of his observations were made during his stay on the island of Lesbo ...
, from insects that produced only a grub, to fish that laid eggs, and on up to animals with blood and live birth. The medieval chain, as in Ramon Lull
Ramon Llull (; c. 1232 – c. 1315/16) was a philosopher, theologian, poet, missionary, and Christian apologist from the Kingdom of Majorca.
He invented a philosophical system known as the ''Art'', conceived as a type of universal logic to pro ...
's ''Ladder of Ascent and Descent of the Mind'', 1305, added steps or levels above humans, with orders of angels reaching up to God at the top.
Pre-Darwinian
The orthogenesis hypothesis had a significant following in the 19th century when evolutionary mechanisms such as Lamarckism
Lamarckism, also known as Lamarckian inheritance or neo-Lamarckism, is the notion that an organism can pass on to its offspring physical characteristics that the parent organism acquired through use or disuse during its lifetime. It is also calle ...
were being proposed. The French zoologist Jean-Baptiste Lamarck
Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (1 August 1744 – 18 December 1829), often known simply as Lamarck (; ), was a French naturalist, biologist, academic, and soldier. He was an early proponent of the idea that biologi ...
(1744–1829) himself accepted the idea, and it had a central role in his theory of inheritance of acquired characteristics, the hypothesized mechanism of which resembled the "mysterious inner force" of orthogenesis. Orthogenesis was particularly accepted by paleontologists who saw in their fossils a directional change, and in invertebrate paleontology
Invertebrate paleontology (also spelled invertebrate palaeontology) is sometimes described as invertebrate paleozoology or invertebrate paleobiology.
Whether it is considered to be a subfield of paleontology, paleozoology, or paleobiology, this d ...
thought there was a gradual and constant directional change. Those who accepted orthogenesis in this way, however, did not necessarily accept that the mechanism that drove orthogenesis was teleological
Teleology (from and )Partridge, Eric. 1977''Origins: A Short Etymological Dictionary of Modern English'' London: Routledge, p. 4187. or finalityDubray, Charles. 2020 912Teleology" In ''The Catholic Encyclopedia'' 14. New York: Robert Appleton ...
(had a definite goal). Charles Darwin
Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended fr ...
himself rarely used the term "evolution" now so commonly used to describe his theory, because the term was strongly associated with orthogenesis, as had been common usage since at least 1647. His grandfather, the physician and polymath Erasmus Darwin
Erasmus Robert Darwin (12 December 173118 April 1802) was an English physician. One of the key thinkers of the Midlands Enlightenment, he was also a natural philosopher, physiologist, slave-trade abolitionist, inventor, and poet.
His poems ...
, was both progressionist and vitalist
Vitalism is a belief that starts from the premise that "living organisms are fundamentally different from non-living entities because they contain some non-physical element or are governed by different principles than are inanimate things." Wher ...
, seeing "the whole cosmos sa living thing propelled by an internal vital force" towards "greater perfection". Robert Chambers, in his popular anonymously published 1844 book ''Vestiges of the Natural History of Creation
''Vestiges of the Natural History of Creation'' is an 1844 work of speculative natural history and philosophy by Robert Chambers. Published anonymously in England, it brought together various ideas of stellar evolution with the progressive tra ...
'' presented a sweeping narrative account of cosmic transmutation, culminating in the evolution of humanity. Chambers included detailed analysis of the fossil record.
With Darwin
Ruse observed that "Progress ''(sic, his capitalisation)'' became essentially a nineteenth-century belief. It gave meaning to life—it offered inspiration—after the collapse ith_Malthus's_pessimism_and_the_shock_of_the_French_revolution.html" ;"title="Malthus.html" ;"title="ith Malthus">ith Malthus's pessimism and the shock of the French revolution">Malthus.html" ;"title="ith Malthus">ith Malthus's pessimism and the shock of the French revolution] of the foundations of the past."
The Baltic German biologist Karl Ernst von Baer (1792–1876) argued for an orthogenetic force in nature, reasoning in a review of Darwin's 1859 ''On the Origin of Species'' that "Forces which are not directed—so-called blind forces—can never produce order."
In 1864, the Swiss anatomist Albert von Kölliker (1817–1905) presented his orthogenetic theory, '' heterogenesis'', arguing for wholly separate lines of descent with no common ancestor.
In 1884, the Swiss botanist Carl Nägeli
Carl Wilhelm von Nägeli (26 or 27 March 1817 – 10 May 1891) was a Swiss people, Swiss botany, botanist. He studied cell division and pollination but became known as the man who discouraged Gregor Mendel from further work on genetics. He reje ...
(1817–1891) proposed a version of orthogenesis involving an "inner perfecting principle". Gregor Mendel
Gregor Johann Mendel, Augustinians, OSA (; cs, Řehoř Jan Mendel; 20 July 1822 – 6 January 1884) was a biologist, meteorologist, mathematician, Augustinians, Augustinian friar and abbot of St Thomas's Abbey, Brno, St. Thomas' Abbey in Br ...
died that same year; Nägeli, who proposed that an " idioplasm" transmitted inherited characteristics, dissuaded Mendel from continuing to work on plant genetics. According to Nägeli many evolutionary developments were nonadaptive and variation was internally programmed. Charles Darwin
Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended fr ...
saw this as a serious challenge, replying that "There must be some efficient cause for each slight individual difference", but was unable to provide a specific answer without knowledge of genetics. Further, Darwin was himself somewhat progressionist, believing for example that "Man" was "higher" than the barnacles he studied.
Darwin indeed wrote in his 1859 ''Origin of Species
''On the Origin of Species'' (or, more completely, ''On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life''),The book's full original title was ''On the Origin of Species by Me ...
'':
In 1898, after studying butterfly
Butterflies are insects in the macrolepidopteran clade Rhopalocera from the Order (biology), order Lepidoptera, which also includes moths. Adult butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. The ...
coloration, ">Theodor Eimer (1843–1898) introduced the term orthogenesis with a widely read book, ''On Orthogenesis: And the Impotence of Natural Selection in Species Formation''. Eimer claimed there were trends in evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
with no adaptive
Adaptation, in biology, is the process or trait by which organisms or population better match their environment
Adaptation may also refer to:
Arts
* Adaptation (arts), a transfer of a work of art from one medium to another
** Film adaptation, a ...
significance that would be difficult to explain by natural selection. To supporters of orthogenesis, in some cases species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
could be led by such trends to extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
. Eimer linked orthogenesis to neo-Lamarckism
Lamarckism, also known as Lamarckian inheritance or neo-Lamarckism, is the notion that an organism can pass on to its offspring physical characteristics that the parent organism acquired through use or disuse during its lifetime. It is also calle ...
in his 1890 book ''Organic Evolution as the Result of the Inheritance of Acquired Characteristics According to the Laws of Organic Growth''. He used examples such as the evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
of the horse
The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million y ...
to argue that evolution had proceeded in a regular single direction that was difficult to explain by random variation. Gould described Eimer as a materialist
Materialism is a form of philosophical monism which holds matter to be the fundamental substance in nature, and all things, including mental states and consciousness, are results of material interactions. According to philosophical materialis ...
who rejected any vitalist
Vitalism is a belief that starts from the premise that "living organisms are fundamentally different from non-living entities because they contain some non-physical element or are governed by different principles than are inanimate things." Wher ...
or teleological
Teleology (from and )Partridge, Eric. 1977''Origins: A Short Etymological Dictionary of Modern English'' London: Routledge, p. 4187. or finalityDubray, Charles. 2020 912Teleology" In ''The Catholic Encyclopedia'' 14. New York: Robert Appleton ...
approach to orthogenesis, arguing that Eimer's criticism of natural selection was common amongst many evolutionists of his generation; they were searching for alternative mechanisms, as they had come to believe that natural selection could not create new species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
.
Nineteenth and twentieth centuries
Numerous versions of orthogenesis (see table) have been proposed. Debate centred on whether such theories were scientific, or whether orthogenesis was inherently vitalistic or essentially theological.[ For example, biologists such as Maynard M. Metcalf (1914), ]John Merle Coulter
John Merle Coulter, Ph. D. (November 20, 1851 – December 23, 1928) was an American botanist and educator. In his career in education administration, Coulter is notable for serving as the president of Indiana University and Lake Forest College a ...
(1915), David Starr Jordan
David Starr Jordan (January 19, 1851 – September 19, 1931) was the founding president of Stanford University, serving from 1891 to 1913. He was an ichthyologist during his research career. Prior to serving as president of Stanford Univer ...
(1920) and Charles B. Lipman (1922) claimed evidence for orthogenesis in bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
, fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
populations and plant
Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...
s.
In 1950, the German paleontologist Otto Schindewolf
Otto Heinrich Schindewolf (7 June 1896 – 10 June 1971) was a German paleontologist who studied the evolution of corals and cephalopods.
Biography
Schindewolf was on the faculty at the University of Marburg from 1919 until 1927. Then he beca ...
argued that variation tends to move in a predetermined direction. He believed this was purely mechanistic, denying any kind of vitalism
Vitalism is a belief that starts from the premise that "living organisms are fundamentally different from non-living entities because they contain some non-physical element or are governed by different principles than are inanimate things." Wher ...
, but that evolution occurs due to a periodic cycle of evolutionary processes dictated by factors internal to the organism.
In 1964 George Gaylord Simpson
George Gaylord Simpson (June 16, 1902 – October 6, 1984) was an American paleontologist. Simpson was perhaps the most influential paleontologist of the twentieth century, and a major participant in the Modern synthesis (20th century), modern ...
argued that orthogenetic theories such as those promulgated by Du Noüy and Sinnott were essentially theology rather than biology.
Though evolution is not progressive, it does sometimes proceed in a linear way, reinforcing characteristics in certain lineages, but such examples are entirely consistent with the modern neo-Darwinian theory of evolution. These examples have sometimes been referred to as ''orthoselection'' but are not strictly orthogenetic, and simply appear as linear and constant changes because of environmental and molecular constraints on the direction of change. The term orthoselection was first used by Ludwig Hermann Plate
Ludwig Hermann Plate (16 August 1862 – 16 November 1937) was a German zoologist and student of Ernst Haeckel. He wrote a "thorough and extensive defence" of Darwinism, but before Mendel's work had been assimilated in the modern synthesis.
...
, and was incorporated into the modern synthesis
Modern synthesis or modern evolutionary synthesis refers to several perspectives on evolutionary biology, namely:
* Modern synthesis (20th century), the term coined by Julian Huxley in 1942 to denote the synthesis between Mendelian genetics and s ...
by Julian Huxley
Sir Julian Sorell Huxley (22 June 1887 – 14 February 1975) was an English evolutionary biologist, eugenicist, and internationalist. He was a proponent of natural selection, and a leading figure in the mid-twentieth century modern synthesis. ...
and Bernard Rensch
Bernhard Rensch (21 January 1900 – 4 April 1990) was a German evolutionary biologist and ornithologist who did field work in Indonesia and India. Starting his scientific career with pro-Lamarckian views, he shifted to selectionism and became o ...
.
Recent work has supported the mechanism and existence of mutation-biased adaptation, meaning that limited local orthogenesis is now seen as possible.
Theories
For the columns for other philosophies of evolution (i.e., combined theories including any of Lamarckism, Mutationism, Natural selection, and Vitalism), "yes" means that person definitely supports the theory; "no" means explicit opposition to the theory; a blank means the matter is apparently not discussed, not part of the theory.
The various alternatives to Darwinian evolution by natural selection were not necessarily mutually exclusive. The evolutionary philosophy of the American palaeontologist Edward Drinker Cope
Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American zoologist, paleontologist, comparative anatomist, herpetologist, and ichthyologist. Born to a wealthy Quaker family, Cope distinguished himself as a child prodigy interested ...
is a case in point. Cope, a religious man, began his career denying the possibility of evolution. In the 1860s, he accepted that evolution could occur, but, influenced by Agassiz, rejected natural selection. Cope accepted instead the theory of recapitulation of evolutionary history during the growth of the embryo - that ontogeny recapitulates phylogeny
Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the egg to adult. The term can also be used to refer to the stu ...
, which Agassiz believed showed a divine plan leading straight up to man, in a pattern revealed both in embryology
Embryology (from Greek ἔμβρυον, ''embryon'', "the unborn, embryo"; and -λογία, '' -logia'') is the branch of animal biology that studies the prenatal development of gametes (sex cells), fertilization, and development of embryos and ...
and palaeontology
Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...
. Cope did not go so far, seeing that evolution created a branching tree of forms, as Darwin had suggested. Each evolutionary step was however non-random: the direction was determined in advance and had a regular pattern (orthogenesis), and steps were not adaptive but part of a divine plan (theistic evolution). This left unanswered the question of why each step should occur, and Cope switched his theory to accommodate functional adaptation for each change. Still rejecting natural selection as the cause of adaptation, Cope turned to Lamarckism to provide the force guiding evolution. Finally, Cope supposed that Lamarckian use and disuse operated by causing a vitalist growth-force substance, "bathmism", to be concentrated in the areas of the body being most intensively used; in turn, it made these areas develop at the expense of the rest. Cope's complex set of beliefs thus assembled five evolutionary philosophies: recapitulationism, orthogenesis, theistic evolution, Lamarckism, and vitalism. Other palaeontologists and field naturalists continued to hold beliefs combining orthogenesis and Lamarckism until the modern synthesis in the 1930s.
Status
In science
The stronger versions of the orthogenetic hypothesis began to lose popularity when it became clear that they were inconsistent with the patterns found by paleontologists
Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...
in the fossil record
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...
, which were non-rectilinear (richly branching) with many complications. The hypothesis was abandoned by the mainstream of evolutionists when no mechanism could be found that would account for the process, and the theory of evolution by natural selection came to prevail. The historian of biology Edward J. Larson commented that
The modern synthesis
Modern synthesis or modern evolutionary synthesis refers to several perspectives on evolutionary biology, namely:
* Modern synthesis (20th century), the term coined by Julian Huxley in 1942 to denote the synthesis between Mendelian genetics and s ...
of the 1930s and 1940s, in which the 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
Heredity, also called inheritance or biological inheritance, is the passing on of traits from parents to their offspring; either through asexual reproduction or sexual reproduction, the offspring cells or organisms acquire the genetic inform ...
could be far-sighted or have a memory of past trends. Orthogenesis was seen to lie outside the methodological naturalism
In philosophy, naturalism is the idea or belief that only natural laws and forces (as opposed to supernatural ones) operate in the universe.
According to philosopher Steven Lockwood, naturalism can be separated into an ontological sense and a me ...
of the sciences.
By 1948, the evolutionary biologist Ernst Mayr
Ernst Walter Mayr (; 5 July 1904 – 3 February 2005) was one of the 20th century's leading evolutionary biologists. He was also a renowned Taxonomy (biology), taxonomist, tropical explorer, ornithologist, Philosophy of biology, philosopher o ...
, 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."[ With the rise of ]evolutionary developmental biology
Evolutionary developmental biology (informally, evo-devo) is a field of biological research that compares the developmental processes of different organisms to infer how developmental processes evolved.
The field grew from 19th-century beginni ...
in the late 20th-early 21st centuries, however, which is open to an expanded concept of heredity that incorporates the physics of self-organization
Self-organization, also called spontaneous order in the social sciences, is a process where some form of overall order arises from local interactions between parts of an initially disordered system. The process can be spontaneous when suffi ...
, ideas of constraint and preferred directions of morphological change have made a reappearance in evolutionary theory.
For these and other reasons, belief in evolutionary progress has remained "a persistent heresy
Heresy is any belief or theory that is strongly at variance with established beliefs or customs, in particular the accepted beliefs of a church or religious organization. The term is usually used in reference to violations of important religi ...
", among evolutionary biologists including E. O. Wilson
Edward Osborne Wilson (June 10, 1929 – December 26, 2021) was an American biologist, naturalist, entomologist and writer. According to David Attenborough, Wilson was the world's leading expert in his specialty of myrmecology, the study of an ...
and Simon Conway Morris
Simon Conway Morris (born 1951) is an English palaeontologist, evolutionary biologist, and astrobiologist known for his study of the fossils of the Burgess Shale and the Cambrian explosion. The results of these discoveries were celebrated in ...
, although often denied or veiled. The philosopher of biology Michael Ruse
Michael Ruse (born 21 June 1940) is a British-born Canadian philosopher of science who specializes in the philosophy of biology and works on the relationship between science and religion, the creation–evolution controversy, and the demarcatio ...
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." He argued that progressionism has harmed the status of evolutionary biology
Evolutionary biology is the subfield of biology that studies the evolutionary processes (natural selection, common descent, speciation) that produced the diversity of life on Earth. It is also defined as the study of the history of life fo ...
as a mature, professional science. Presentations of evolution remain characteristically progressionist, with humans at the top of the "Tower of Time" in the Smithsonian Institution
The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums and education and research centers, the largest such complex in the world, created by the U.S. government "for the increase and diffusion of knowledge". Founded ...
in Washington D.C.
)
, image_skyline =
, image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morgan, Na ...
, while ''Scientific American
''Scientific American'', informally abbreviated ''SciAm'' or sometimes ''SA'', is an American popular science magazine. Many famous scientists, including Albert Einstein and Nikola Tesla, have contributed articles to it. In print since 1845, it i ...
'' 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.
In popular culture
In popular culture, progressionist images of evolution are widespread. The historian Jennifer Tucker, writing in ''The Boston Globe
''The Boston Globe'' is an American daily newspaper founded and based in Boston, Massachusetts. The newspaper has won a total of 27 Pulitzer Prizes, and has a total circulation of close to 300,000 print and digital subscribers. ''The Boston Glob ...
'', notes that Thomas Henry Huxley
Thomas Henry Huxley (4 May 1825 – 29 June 1895) was an English biologist and anthropologist specialising in comparative anatomy. He has become known as "Darwin's Bulldog" for his advocacy of Charles Darwin's theory of evolution.
The storie ...
's 1863 illustration comparing the skeletons of apes and humans "has become an iconic and instantly recognizable visual shorthand for evolution." 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
Stephen Jay Gould (; September 10, 1941 – May 20, 2002) was an American paleontologist, evolutionary biologist, and historian of science. He was one of the most influential and widely read authors of popular science of his generation. Gould sp ...
in '' Wonderful Life''.
Popular perception, however, had seized upon the idea of linear progress. Edward Linley Sambourne
Edward Linley Sambourne (4 January 18443 August 1910) was an English cartoonist and illustrator most famous for being a draughtsman for the satirical magazine ''Punch'' for more than forty years and rising to the position of "First Cartoonist" i ...
'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
Michelangelo di Lodovico Buonarroti Simoni (; 6 March 1475 – 18 February 1564), known as Michelangelo (), was an Italian sculptor, painter, architect, and poet of the High Renaissance. Born in the Republic of Florence, his work was insp ...
's figure of Adam
Adam; el, Ἀδάμ, Adám; la, Adam is the name given in Genesis 1-5 to the first human. Beyond its use as the name of the first man, ''adam'' is also used in the Bible as a pronoun, individually as "a human" and in a collective sense as " ...
in his fresco adorning the ceiling of the Sistine Chapel
The Sistine Chapel (; la, Sacellum Sixtinum; it, Cappella Sistina ) is a chapel in the Apostolic Palace, the official residence of the pope in Vatican City. Originally known as the ''Cappella Magna'' ('Great Chapel'), the chapel takes its name ...
. 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
Neanderthals (, also ''Homo neanderthalensis'' and erroneously ''Homo sapiens neanderthalensis''), also written as Neandertals, are an extinct species or subspecies of archaic humans who lived in Eurasia until about 40,000 years ago. While the ...
, Socrates
Socrates (; ; –399 BC) was a Greek philosopher from Athens who is credited as the founder of Western philosophy and among the first moral philosophers of the ethical tradition of thought. An enigmatic figure, Socrates authored no te ...
, and finally the lawyer William Jennings Bryan
William Jennings Bryan (March 19, 1860 – July 26, 1925) was an American lawyer, orator and politician. Beginning in 1896, he emerged as a dominant force in the History of the Democratic Party (United States), Democratic Party, running ...
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
Rudolph Franz Zallinger (; November 12, 1919 – August 1, 1995) was an American-based Austrian-Russian artist. His most notable works include his mural ''The Age of Reptiles'' (1947) at Yale University's Peabody Museum of Natural History, and th ...
's 1965 " 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.
Sliding between meanings
Scientists, Ruse argues, continue to slide easily from one notion of progress to another: even committed Darwinians like Richard Dawkins
Richard Dawkins (born 26 March 1941) is a British evolutionary biologist and author. He is an emeritus fellow of New College, Oxford and was Professor for Public Understanding of Science in the University of Oxford from 1995 to 2008. An ath ...
embed the idea of cultural progress in a theory of cultural units, meme
A meme ( ) is an idea, behavior, or style that spreads by means of imitation from person to person within a culture and often carries symbolic meaning representing a particular phenomenon or theme. A meme acts as a unit for carrying cultural i ...
s, that act much like genes. Dawkins can speak of "progressive rather than random ... trends in evolution". Dawkins and John Krebs
John Richard Krebs, Baron Krebs, Kt FRS (born 11 April 1945) is an English zoologist researching in the field of behavioural ecology of birds. He was the principal of Jesus College, Oxford, from 2005 until 2015."Elliott Coues Award, 1999: Si ...
deny the "earlier arwinianprejudice" that there is anything "inherently progressive about evolution", but, Ruse argues, the feeling of progress comes from evolutionary arms race
An arms race occurs when two or more groups compete in military superiority. It consists of a competition between two or more states to have superior armed forces; a competition concerning production of weapons, the growth of a military, and t ...
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".
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
Pseudoscience consists of statements, beliefs, or practices that claim to be both scientific and factual but are incompatible with the scientific method. Pseudoscience is often characterized by contradictory, exaggerated or falsifiability, unfa ...
; Darwin made it respectable, but "only as popular science". "There it remained frozen, for nearly another hundred years", until mathematicians such as Fisher provided "both models
A model is an informative representation of an object, person or system. The term originally denoted the plans of a building in late 16th-century English, and derived via French and Italian ultimately from Latin ''modulus'', a measure.
Models c ...
and status", enabling evolutionary biologists to construct the modern synthesis
Modern synthesis or modern evolutionary synthesis refers to several perspectives on evolutionary biology, namely:
* Modern synthesis (20th century), the term coined by Julian Huxley in 1942 to denote the synthesis between Mendelian genetics and s ...
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 iologistsstill firmly committed to Progress" as a philosophy.
Facilitated variation
Biology has largely rejected the idea that evolution is guided in any way, but the evolution of some features is indeed facilitated by the genes of the developmental-genetic toolkit
The evo-devo gene toolkit is the small subset of genes in an organism's genome whose products control the organism's embryonic development. Toolkit genes are central to the synthesis of molecular genetics, palaeontology, evolution and developmen ...
studied in evolutionary developmental biology
Evolutionary developmental biology (informally, evo-devo) is a field of biological research that compares the developmental processes of different organisms to infer how developmental processes evolved.
The field grew from 19th-century beginni ...
. An example is the development of wing pattern in some species of ''Heliconius
''Heliconius'' comprises a colorful and widespread genus of brush-footed butterflies commonly known as the longwings or heliconians. This genus is distributed throughout the tropical and subtropical regions of the New World, from South America a ...
'' butterfly, which have independently evolved similar patterns. These butterflies are Müllerian mimics of each other, so natural selection is the driving force, but their wing patterns, which arose in separate evolutionary events, are controlled by the same genes.
See also
* Adaptive mutation
Adaptive mutation, also called directed mutation or directed mutagenesis is a controversial evolutionary theory. It posits that mutations, or genetic changes, are much less random and more purposeful than traditional evolution, implying that org ...
* Devolution
Devolution is the statutory delegation of powers from the central government of a sovereign state to govern at a subnational level, such as a regional or local level. It is a form of administrative decentralization. Devolved territories h ...
* Directed evolution
Directed evolution (DE) is a method used in protein engineering that mimics the process of natural selection to steer proteins or nucleic acids toward a user-defined goal. It consists of subjecting a gene to iterative rounds of mutagenesis (cre ...
(in protein engineering)
*Directed evolution (transhumanism)
The term directed evolution is used within the transhumanist community to refer to the idea of applying the principles of directed evolution and experimental evolution to the control of human evolution. In this sense, it is distinct from the use ...
* Evolutionism
Evolutionism is a term used (often derogatorily) to denote the theory of evolution. Its exact meaning has changed over time as the study of evolution has progressed. In the 19th century, it was used to describe the belief that organisms deliberate ...
* Evolution of biological complexity
The evolution of biological complexity is one important outcome of the process of evolution. Evolution has produced some remarkably complex organisms – although the actual level of complexity is very hard to define or measure accurately in biolo ...
* History of evolutionary thought
Evolutionary thought, the recognition that species change over time and the perceived understanding of how such processes work, has roots in antiquity—in the ideas of the ancient Greeks, Romans, Chinese, Church Fathers as well as in medie ...
* Structuralism
In sociology, anthropology, archaeology, history, philosophy, and linguistics, structuralism is a general theory of culture and methodology that implies that elements of human culture must be understood by way of their relationship to a broader ...
* Teleonomy
Teleonomy is the quality of apparent purposefulness and of goal-directedness of structures and functions in living organisms brought about by natural processes like natural selection. The term derives from the Greek "τελεονομία", compound ...
*Teleological argument
The teleological argument (from ; also known as physico-theological argument, argument from design, or intelligent design argument) is an argument for the existence of God or, more generally, that complex functionality in the natural world wh ...
References
Sources
*
*
*
*
*
Further reading
* Bateson, William (1909).
Heredity and variation in modern lights
, in ''Darwin and Modern Science'' (A.C. Seward ed.) Cambridge University Press. Chapter V.
* Dennett, Daniel (1995). ''Darwin's Dangerous Idea
''Darwin's Dangerous Idea: Evolution and the Meanings of Life'' is a 1995 book by the philosopher Daniel Dennett, in which the author looks at some of the repercussions of Darwinian theory. The crux of the argument is that, whether or not Darwin ...
''. Simon & Schuster. .
* Huxley, Julian (1942). '' Evolution: The Modern Synthesis'', London: George Allen and Unwin.
*
* Simpson, George G. (1957). ''Life Of The Past: Introduction to Paleontology''. Yale University Press, p. 119.
* Wilkins, John (1997)
"What is macroevolution?"
13 October 2004.
External links
{{Evolution
Non-Darwinian evolution
History of evolutionary biology
Teleology
Vitalism
Obsolete biology theories