Hugo de Vries
Encyclopedia
Hugo Marie de Vries ForMemRS
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

 (ˈhyxoː də ˈvriːs) (February 16, 1848, Haarlem
Haarlem
Haarlem is a municipality and a city in the Netherlands. It is the capital of the province of North Holland, the northern half of Holland, which at one time was the most powerful of the seven provinces of the Dutch Republic...

 – May 21, 1935, Lunteren
Lunteren
Lunteren is a place in Gelderland Province, Netherlands. It has a railway station and the train travels between Amersfoort and Ede.It is known also because of three Conference Centres in the vicinity, like Het Bosgoed, which hosting especially academic conferences and De Werelt Congress Hotel.It...

) was a Dutch
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 botanist and one of the first geneticist
Geneticist
A geneticist is a biologist who studies genetics, the science of genes, heredity, and variation of organisms. A geneticist can be employed as a researcher or lecturer. Some geneticists perform experiments and analyze data to interpret the inheritance of skills. A geneticist is also a Consultant or...

s. He is known chiefly for suggesting the concept of gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

s, rediscovering the laws of heredity in the 1890s while unaware of Gregor Mendel
Gregor Mendel
Gregor Johann Mendel was an Austrian scientist and Augustinian friar who gained posthumous fame as the founder of the new science of genetics. Mendel demonstrated that the inheritance of certain traits in pea plants follows particular patterns, now referred to as the laws of Mendelian inheritance...

's work, for introducing the term "mutation", and for developing a mutation theory of evolution.

Early life

De Vries was born in 1848, the oldest son of Gerrit de Vries
Gerrit de Vries (politician)
Mr. Gerrit Abrahamsz de Vries was a Dutch jurist and politician. He was Prime Minister of the Netherlands from 4 June 1872 to 27 August 1874.-References:* in Elsevier, 21 April 2009 ....

 (1818–1900), a lawyer and deacon in the Mennonite congregation in Haarlem and later Prime Minister of the Netherlands from 1872 until 1874, and Maria Everardina Reuvens (1823–1914), daughter of a professor in archaeology at Leiden University
Leiden University
Leiden University , located in the city of Leiden, is the oldest university in the Netherlands. The university was founded in 1575 by William, Prince of Orange, leader of the Dutch Revolt in the Eighty Years' War. The royal Dutch House of Orange-Nassau and Leiden University still have a close...

. His father became a member of the Dutch Council of State
Dutch Council of State
In the Netherlands, the Council of State is a constitutionally established advisory body to the government which consists of members of the royal family and Crown-appointed members generally having political, commercial, diplomatic, or military experience...

 in 1862 and moved his family over to The Hague
The Hague
The Hague is the capital city of the province of South Holland in the Netherlands. With a population of 500,000 inhabitants , it is the third largest city of the Netherlands, after Amsterdam and Rotterdam...

. From an early age Hugo showed much interest in botany, winning several prizes for his herbarium
Herbarium
In botany, a herbarium – sometimes known by the Anglicized term herbar – is a collection of preserved plant specimens. These specimens may be whole plants or plant parts: these will usually be in a dried form, mounted on a sheet, but depending upon the material may also be kept in...

s while attending gymnasium
Gymnasium (school)
A gymnasium is a type of school providing secondary education in some parts of Europe, comparable to English grammar schools or sixth form colleges and U.S. college preparatory high schools. The word γυμνάσιον was used in Ancient Greece, meaning a locality for both physical and intellectual...

 in Haarlem and The Hague.

In 1866 he enrolled at the Leiden University to major in botany. He enthusiastically took part in W.F.R. Suringar's classes and excursions, but was mostly drawn to the experimental botany outlined in Julius Sachs' 'Lehrbuch der Botanik' from 1868. He was also deeply impressed by Charles Darwin
Charles Darwin
Charles Robert Darwin FRS was an English naturalist. He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection.He published his theory...

's evolution theory, despite Suringar's skepticism. He wrote a dissertation on the effect of heat on plant roots, including several statements by Darwin to provoke his professor, and graduated in 1870.

Early career

After a short period of teaching, De Vries left in September 1870 to take classes in chemistry and physics at the Heidelberg University and work in the laboratory of Wilhelm Hofmeister
Wilhelm Hofmeister
Wilhelm Friedrich Benedikt Hofmeister was a German biologist and botanist. He "stands as one of the true giants in the history of biology and belongs in the same pantheon as Darwin and Mendel." He was largely self-taught....

. In the second semester of that school year he joined the lab of the esteemed Julius Sachs in Würzburg
Würzburg
Würzburg is a city in the region of Franconia which lies in the northern tip of Bavaria, Germany. Located at the Main River, it is the capital of the Regierungsbezirk Lower Franconia. The regional dialect is Franconian....

 to study plant growth. From September 1871 until 1875 he taught botany, zoology, and geology at schools in Amsterdam
Amsterdam
Amsterdam is the largest city and the capital of the Netherlands. The current position of Amsterdam as capital city of the Kingdom of the Netherlands is governed by the constitution of August 24, 1815 and its successors. Amsterdam has a population of 783,364 within city limits, an urban population...

. During each vacation he returned to the lab in Heidelberg to continue his research.

In 1875 the Prussian Ministry of Agriculture offered De Vries a position as professor at the still to be constructed Landwirtschaftliche Hochschule ("Royal Agricultural College") in Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...

. In anticipation, he moved back to Würzburg, where he studied agricultural crops and collaborated with Sachs. By 1877, Berlin's College was still only a plan, and he briefly took up a position teaching at the University of Halle-Wittenberg
University of Halle-Wittenberg
The Martin Luther University of Halle-Wittenberg , also referred to as MLU, is a public, research-oriented university in the cities of Halle and Wittenberg within Saxony-Anhalt, Germany...

. The same year he was offered a position as lecturer in plant physiology at the newly founded University of Amsterdam. He was made adjunct professor in 1878 and full professor on his birthday in 1881, partly to keep him from moving to the Berlin College, which finally opened that year.
De Vries was also professor and director of Amsterdam's Botanical Institute and Garden
Hortus Botanicus (Amsterdam)
Hortus Botanicus is a botanical garden in Amsterdam, the Netherlands. One of the oldest in the world, it is one of Amsterdam's major tourist attractions.- History:...

 from 1885 to 1918.

Definition of the gene

In 1889, De Vries published his book Intracellular Pangenesis, in which, based on a modified version of Charles Darwin
Charles Darwin
Charles Robert Darwin FRS was an English naturalist. He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection.He published his theory...

's theory of Pangenesis
Pangenesis
Pangenesis was Charles Darwin's hypothetical mechanism for heredity. He presented this 'provisional hypothesis' in his 1868 work The Variation of Animals and Plants under Domestication and felt that it brought 'together a multitude of facts which are at present left disconnected by any efficient...

 of 1868, he postulated that different characters have different hereditary carriers. He specifically postulated that inheritance of specific traits in organisms comes in particles. He called these units pangenes, a term 20 years later to be shortened to gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

s by Wilhelm Johannsen
Wilhelm Johannsen
Wilhelm Johannsen was a Danish botanist, plant physiologist and geneticist. He was born in Copenhagen. While very young, he was apprenticed to a pharmacist and worked in Denmark and Germany beginning in 1872 until passing his pharmacist's exam in 1879...

.

Rediscovery of genetics

To support his theory of pangenes, which was not widely noticed at the time, De Vries conducted a series of experiments hybridising varieties of multiple plant species in the 1890s. Unaware of Mendel's work, De Vries used the laws of dominance and recessiveness, segregation, and independent assortment to explain the 3:1 ratio of phenotype
Phenotype
A phenotype is an organism's observable characteristics or traits: such as its morphology, development, biochemical or physiological properties, behavior, and products of behavior...

s in the second generation. His observations also confirmed his hypothesis that inheritance of specific traits in organisms comes in particles.

He further speculated that genes could cross the species barrier, with the same gene being responsible for hairiness in two different species of flower. Although generally true in a sense (orthologous genes, inherited from a common ancestor of both species, tend to stay responsible for similar phenotypes), De Vries meant a physical cross between species. This actually also happens, though very rarely in higher organisms (see horizontal gene transfer
Horizontal gene transfer
Horizontal gene transfer , also lateral gene transfer , is any process in which an organism incorporates genetic material from another organism without being the offspring of that organism...

).

In the late 1890s, De Vries became aware of Mendel's obscure paper of thirty years earlier and he altered some of his terminology to match. When he published the results of his experiments in the French journal Comtes Rendus de l'Académie des Sciences in 1900, he neglected to mention Mendel's work, but after criticism by Carl Correns
Carl Correns
Carl Erich Correns was a German botanist and geneticist, who is notable primarily for his independent discovery of the principles of heredity, and for his rediscovery of Gregor Mendel's earlier paper on that subject, which he achieved simultaneously but independently of the botanists Erich...

 he conceded Mendel's priority.

Correns and Erich von Tschermak
Erich von Tschermak
Erich von Tschermak-Seysenegg was an Austrian agronomist who developed several new disease-resistant crops, including wheat-rye and oat hybrids. He was a son of the Moravia-born mineralogist Gustav Tschermak von Seysenegg...

 now share credit for the rediscovery of Mendel’s laws. Correns was a student of Nägeli, a renowned botanist with whom Mendel corresponded about his work with peas but who failed to understand its significance, while, coincidentally, Tschermak's grandfather taught Mendel botany during his student days in Vienna.

Mutation theory

In his own time, De Vries was best known for his mutation theory. In 1886 he had discovered new forms among a display of the evening primrose
Oenothera
Oenothera is a Genus of about 125 species of annual, biennial and perennial herbaceous flowering plants, native to North and South America. It is the type genus of the family Onagraceae, the Evening Primrose Family. Common names include evening-primrose, suncups, and sundrops.The species vary in...

 (Oenothera lamarckiana) growing wild in a meadow. Taking seeds from these, he found that they produced many new varieties in his experimental gardens; he introduced the term mutations for these suddenly appearing variations. In his two-volume publication The Mutation Theory (1900–1903) he postulated that evolution, especially the origin of species, might occur more frequently with such large-scale changes than via Darwinian gradualism, basically suggesting a form of saltationism
Saltation (biology)
In biology, ""saltation"" is a sudden change from one generation to the next, that is large, or very large, in comparison with the usual variation of an organism...

. De Vries's theory was one of the chief contenders for the explanation of how evolution worked, leading, for example, Thomas Hunt Morgan
Thomas Hunt Morgan
Thomas Hunt Morgan was an American evolutionary biologist, geneticist and embryologist and science author who won the Nobel Prize in Physiology or Medicine in 1933 for discoveries relating the role the chromosome plays in heredity.Morgan received his PhD from Johns Hopkins University in zoology...

 to study mutations in the fruit fly, until the modern evolutionary synthesis
Modern evolutionary synthesis
The modern evolutionary synthesis is a union of ideas from several biological specialties which provides a widely accepted account of evolution...

 became the dominant model in the 1930s. Somewhat ironically, the large-scale primrose variations turned out to be the result of chromosomal duplications (polyploidy
Polyploidy
Polyploid is a term used to describe cells and organisms containing more than two paired sets of chromosomes. Most eukaryotic species are diploid, meaning they have two sets of chromosomes — one set inherited from each parent. However polyploidy is found in some organisms and is especially common...

), while the term mutation now generally is restricted to discrete changes in the DNA sequence.

Finally, in a published lecture of 1903 (Befruchtung und Bastardierung, Veit, Leipzig), De Vries was also the first to suggest the occurrence of recombinations between homologous chromosome
Homologous chromosome
Homologous chromosomes are chromosome pairs of approximately the same length, centromere position, and staining pattern, with genes for the same characteristics at corresponding loci. One homologous chromosome is inherited from the organism's mother; the other from the organism's father...

s, now known as chromosomal crossover
Chromosomal crossover
Chromosomal crossover is an exchange of genetic material between homologous chromosomes. It is one of the final phases of genetic recombination, which occurs during prophase I of meiosis in a process called synapsis. Synapsis begins before the synaptonemal complex develops, and is not completed...

s, within a year after chromosomes were implicated in Mendelian inheritance by Walter Sutton
Walter Sutton
Walter Stanborough Sutton was an American geneticist and physician whose most significant contribution to present-day biology was his theory that the Mendelian laws of inheritance could be applied to chromosomes at the cellular level of living organisms...

.

Honors and retirement

In May 1905, De Vries was elected Foreign Member of the Royal Society. In 1910, he was elected a member of the Royal Swedish Academy of Sciences
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademien is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2...

. He was awarded the Darwin Medal
Darwin Medal
The Darwin Medal is awarded by the Royal Society every alternate year for "work of acknowledged distinction in the broad area of biology in which Charles Darwin worked, notably in evolution, population biology, organismal biology and biological diversity". First awarded in 1890, it was created in...

 in 1906 and the Linnean Medal
Linnean Medal
The Linnean Medal of the Linnean Society of London was established in 1888, and is awarded annually to alternately a botanist or a zoologist or to one of each in the same year...

 in 1929.

He retired in 1918 from the University of Amsterdam and withdrew to his estate "De Boeckhorst" in Lunteren
Lunteren
Lunteren is a place in Gelderland Province, Netherlands. It has a railway station and the train travels between Amersfoort and Ede.It is known also because of three Conference Centres in the vicinity, like Het Bosgoed, which hosting especially academic conferences and De Werelt Congress Hotel.It...

 where he had large experimental gardens. He continued his studies with new forms until his death in 1935.

Books

His best known works are:

External links

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