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Encyclopedia > 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 cause'. Charles Darwin, about the same time as the publication of The Origin of Species. ... For the scientific journal Heredity see Heredity (journal) Heredity (the adjective is hereditary) is the transfer of characters from parent to offspring, either through their genes or through the social institution called inheritance (for example, a title of nobility is passed from individual to individual according to relevant customs and... 1868 was a leap year starting on Wednesday (see link for calendar). ...


The theory itself is now seen as deeply flawed and not supported by observation, yet it represents Darwin's attempt to explain such diverse phenomona as

Simply put, the theory holds that body cells shed 'gemmules' which collect in the reproductive organs prior to fertilization. Thus every cell in the body has a 'vote' in the constitution of the offspring. Atavisms arise due to the awaking of long-dormant gemmules while limbs regenerate due to the activation of gemmules from the missing limb which circulate in the main part of the body. During the interval between the acceptance of Darwinian evolution and the rise of modern understanding of genetics, atavism was used to account for the reappearance in an individual of a trait after several generations of absence. ... This article is about a biological term. ... Jean-Baptiste Pierre Antoine de Monet, Chevalier de Lamarck (August 1, 1744 - December 28, 1829) was a major 19th century naturalist, who was one of the first to use the term biology in its modern sense. ... Regeneration is the ability to restore lost or damaged tissues, organs or limbs. ...


In his later work, The Descent of Man, Darwin elaborated further on the model. In a section on the "Laws of inheritance," Darwin specified that two elements in particular were most important: the transmission and the development of inherited characteristics. Darwin's insights were that characteristics could be transmitted which were not at the time of transmission actually being manifest in the parent organism, and that certain traits would manifest themselves at the same point of development (say, old age) in both the parent and child organisms. In order to make sense of his theory of sexual selection, he also stipulated that certain traits could be passed through organisms but would only develop depending on the sex of the organism in question. The Descent of Man and Selection in Relation to Sex by British naturalist Charles Darwin was first published in 1871. ... Illustration from The Descent of Man and Selection in Relation to Sex by Charles Darwin showing the tufted coquette Lophornis ornatus, female on left, ornamented male on right. ...


While the theory was of little use for biologists, it proved exceedingly useful to the nascent science of statistics, and was taken up in a major way by his cousin Francis Galton in his development of the "biometric" approach to heredity. Galton eventually discarded the notion that somatic cells (and thus, acquired characteristics) could contribute to an individual's heredity, but appreciated that an individual embryo would contain many more gemmules than would actually be expressed. This is now interpretted as a crude, but insightful, first approach to the question of inherited, but unexpressed, characteristics. So useful to the biometricians was the theory of pangenesis that it continued to be used for some time after the "rediscovery" of Mendel's laws completely replaced it in the biological community. The two approaches were later merged in the 1930s by R.A. Fisher in what eventually became known as the modern synthesis. Statistics is the science and practice of developing knowledge through the use of empirical data expressed in quantitative form. ... Francis Galton Sir Francis Galton FRS (February 16, 1822 - January 17, 1911) was an English explorer, statistician, anthropologist, creator of modern eugenics (he coined the term), and investigator of the human mind. ... Mendelian inheritance (or Mendelian genetics or Mendelism) is a set of primary tenets that underlie much of genetics developed by Gregor Mendel in the latter part of the 19th century. ... Sir Ronald Fisher Sir Ronald Aylmer Fisher, FRS (February 17, 1890–July 29, 1962) was an extraordinarily talented evolutionary biologist, geneticist and statistician. ... The modern evolutionary synthesis (often referred to simply as the modern synthesis), neo-Darwinian synthesis or neo-Darwinism, brings together Charles Darwins theory of the evolution of species by natural selection with Gregor Mendels theory of genetics as the basis for biological inheritance. ...


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Pangenesis Information (450 words)
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 cause'.
So useful to the biometricians was the theory of pangenesis that it continued to be used for some time after the "rediscovery" of Mendel's laws completely replaced it in the biological community.
Genetics - Printer-friendly - MSN Encarta (2223 words)
The theories about the inheritance of acquired characteristics and pangenesis persisted until the middle of the 19th century.
A surprising supporter of pangenesis was the British naturalist Charles Robert Darwin, who believed that the theory accounted for the process of heredity and the wide variety of traits seen among offspring.
Despite his mistaken belief in pangenesis, Darwin nonetheless had an enormous impact on human understanding of heredity.
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