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Hugo de Vries

Hugo Marie de Vries was a Dutch botanist and one of the first geneticists. He is known chiefly for suggesting the concept of genes, rediscovering the laws of heredity in the 1890s while unaware of Gregor Mendel's work, for introducing the term "mutation", for developing a mutation theory of evolution. De Vries was born in 1848, the eldest son of Gerrit de Vries, a lawyer and deacon in the Mennonite congregation in Haarlem and Prime Minister of the Netherlands from 1872 until 1874, Maria Everardina Reuvens, daughter of a professor in archaeology at Leiden University, his father became a member of the Dutch Council of State in 1862 and moved his family over to The Hague. From an early age Hugo showed much interest in botany, winning several prizes for his herbariums while attending gymnasium 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 drawn to the experimental botany outlined in Julius von Sachs"Lehrbuch der Botanik' from 1868.

He was deeply impressed by Charles Darwin'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, graduated in 1870. 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. In the second semester of that school year he joined the lab of the esteemed Julius Sachs in Würzburg to study plant growth. From September 1871 until 1875 he taught botany and geology at schools in Amsterdam. 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 in Berlin. 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, he took up a position teaching at the University of Halle-Wittenberg.

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 to keep him from moving to the Berlin College, which opened that year. De Vries was professor and director of Amsterdam's Botanical Institute and Garden from 1885 to 1918. In 1889, De Vries published his book Intracellular Pangenesis, in which, based on a modified version of Charles Darwin's theory of Pangenesis of 1868, he postulated that different characters have different hereditary carriers, he postulated that inheritance of specific traits in organisms comes in particles. He called these units pangenes, a term 20 years to be shortened to genes by Wilhelm Johannsen. To support his theory of pangenes, not 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 and independent assortment to explain the 3:1 ratio of phenotypes in the second generation.

His observations 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 true in a sense, De Vries meant a physical cross between species; this also happens, though rarely in higher organisms. De Vries' work on genetics inspired the research of Jantina Tammes, who worked with him for a period in 1898. 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 Comptes rendus de l'Académie des Sciences in 1900, he neglected to mention Mendel's work, but after criticism by Carl Correns he conceded Mendel's priority. Correns and Erich von Tschermak 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, coincidentally, Tschermak's grandfather taught Mendel botany during his student days in Vienna.

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 growing wild in an abandoned potato field near Hilversum, having escaped a nearby garden. Taking seeds from these, he found. In his two-volume publication The Mutation Theory he postulated that evolution the origin of species, might occur more with such large-scale changes than via Darwinian gradualism suggesting a form of saltationism. De Vries's theory was one of the chief contenders for the explanation of how evolution worked, for example, Thomas Hunt Morgan to study mutations in the fruit fly, until the modern evolutionary synthesis became the dominant model in the 1930s. During the early decades of the twentieth century, de Vries' theory was enormously influential and contin

Grove Hill Cemetery

The Grove Hill Cemetery is a historic cemetery at 290 Main Street in Waltham, Massachusetts. Established in 1703, the cemetery was Waltham's only cemetery until 1857, when Mount Feake Cemetery opened, it was authorized in 1703, but its initial 2.3-acre parcel of land was not purchased until 1704. The first documented burial, took place in November 1703; the northwest section of the cemetery is its oldest portion, includes a number of unmarked gravesites. The cemetery continues in active use today, contains a representative sample of funerary art spanning 300 years, it now covers more than 9 acres, extending between Grove Streets. Its main entrance features posts with an Egyptian Revival theme, a style continued with the presence of obelisks dispersed on the grounds; the cemetery was listed on the National Register of Historic Places in 1989. National Register of Historic Places listings in Waltham, Massachusetts

Don Barker (politician)

Charles William Donald Barker was an Australian politician, a Labor Party member of the Legislative Council of Western Australia from 1952 until his death, representing North Province. Barker was born in York and came to Western Australia at the age of 17, working as a station hand in the North-West, he served with the Royal Australian Navy during World War II. On his return to Australia, he ran a café in Broome for a period, worked in Derby as a stock inspector. Barker entered parliament at the 1952 Legislative Council elections, defeating the sitting Liberal member, Mervyn Forrest, by just five votes, he died in office in July 1956, aged 51. In parliament, he was known for his concern for Aboriginal welfare, he and his wife put up visiting Aboriginal students from the North-West at their home in Perth