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Telegony (pregnancy)
Telegony is a theory of heredity holding that offspring can inherit the characteristics of a previous mate of the female parent; thus the child of a woman might partake of traits of a previous sexual partner. The theory used to be accepted as a fact by the Ancient Greeks, but experiments in the late 19th century on several species failed to provide evidence that offspring would inherit any characteristics from their mother's previous mates. Although there is no strong scientific evidence supporting it, the theory of telegony has been revisited by some in light of emerging interest in non-genetic mechanisms of inheritance. Etymology and description Telegony is the idea that a female will be permanently affected when she is first impregnated, since the fetus will pass back characteristics to her that will affect all future offspring, no matter their progeny. The term was coined by August Weismann from the Greek words τῆλε (tèle) meaning 'far' and γονος (gonos) mea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 information of their parents. Through heredity, variations between individuals can accumulate and cause species to evolve by natural selection. The study of heredity in biology is genetics. Overview In humans, eye color is an example of an inherited characteristic: an individual might inherit the "brown-eye trait" from one of the parents. Inherited traits are controlled by genes and the complete set of genes within an organism's genome is called its genotype. The complete set of observable traits of the structure and behavior of an organism is called its phenotype. These traits arise from the interaction of the organism's genotype with the environment. As a result, many aspects of an organism's phenotype are not inherited. For example, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nag Hammadi
Nag Hammadi ( ; ) is a city and Markaz (administrative division), markaz in Upper Egypt. It is located on the west bank of the Nile in the Qena Governorate, about north-west of Luxor. The city had a population of close to 61,737 . History The town of Nag Hammadi was found on the site of older villages Ansan () and al-Luaqi () in the 19th century and was named after its founder, Mahmoud Pasha Hammadi, a member of the Hammadi family in Sohag, Egypt. Mahmoud Pasha Hammadi was a major landholder in Sohag, and known for his strong opposition to the History of Egypt under the British, British rule in Egypt beginning in 1882. In the city of Nag Hammadi, there is the palace of Prince Youssef Kamal, a member of the royal family (the family of Muhammad Ali of Egypt, Muhammad Ali Pasha), which overlooks the Nile River and is now an archaeological site. Nag Hammadi is about west of ancient Sheneset-Chenoboskion, Chenoboskion () The "Nag Hammadi library", an important collection of 2n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Cossar Ewart
James Cossar Ewart Royal Society, FRS FRSE (26 November 1851 – 31 December 1933) was a Scottish zoologist. He performed breeding experiments with horses and zebras which disproved earlier theories of heredity. Life Ewart was born in Penicuik, Midlothian, Scotland, the son of Jean Cossar and John Ewart, a joiner. He studied medicine from 1871 to 1874 at the University of Edinburgh where he graduated with an MB ChB. After graduation, he became an anatomy demonstrator under William Turner (University Principal), William Turner and then held the position of Curator of the Zoological Museum at University College, London, where he assisted Ray Lankester (later director of the Natural History Museum) by making zoological preparations for the museum and providing teaching support for Lankester's course in practical zoology. In 1878 he returned to Scotland to take a post of Regius Professor of Natural History (Aberdeen), Regius Professor of Natural History at the University of Ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herbert Spencer
Herbert Spencer (27 April 1820 – 8 December 1903) was an English polymath active as a philosopher, psychologist, biologist, sociologist, and anthropologist. Spencer originated the expression "survival of the fittest", which he coined in ''Principles of Biology'' (1864) after reading Charles Darwin's 1859 book ''On the Origin of Species''. The term strongly suggests natural selection, yet Spencer saw evolution as extending into realms of sociology and ethics, so he also supported Lamarckism. Riggenbach, Jeff (24 April 2011The Real William Graham Sumner, Mises Institute. Spencer developed an all-embracing conception of evolutionism, evolution as the progressive development of the physical world, biological organisms, the human mind, and human culture and societies. As a polymath, he contributed to a wide range of subjects, including ethics, religion, anthropology, economics, political theory, philosophy, literature, astronomy, biology, sociology, and psychology. During h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schopenhauer
Arthur Schopenhauer ( ; ; 22 February 1788 – 21 September 1860) was a German philosopher. He is known for his 1818 work '' The World as Will and Representation'' (expanded in 1844), which characterizes the phenomenal world as the manifestation of a blind and irrational noumenal will. Building on the transcendental idealism of Immanuel Kant, Schopenhauer developed an atheistic metaphysical and ethical system that rejected the contemporaneous ideas of German idealism. Schopenhauer was among the first philosophers in the Western tradition to share and affirm significant tenets of Indian philosophy, such as asceticism, denial of the self, and the notion of the world-as-appearance. His work has been described as an exemplary manifestation of philosophical pessimism. Though his work failed to garner substantial attention during his lifetime, he had a posthumous impact across various disciplines, including philosophy, literature, and science. His writing on aesthetics, mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Austin Flint (1836–1915)
Austin Flint II (March 28, 1836 – September 21, 1915) was an American physician. He carried out extensive experimental investigations in human physiology and made several important discoveries. He assisted in establishing the glycogenic function of the liver; showed that one of the functions of the liver is to separate from the blood the cholesterin, which is a product of the nervous system. This becomes a constituent of the bile, and is afterward converted into what he named "stercorin" (better known as coprosterol), the odorous principle of feces. Early life He was born on March 28, 1836, in Northampton, Massachusetts, to Austin Flint I (1812–1886), who helped found Bellevue Hospital, and Anne Balch Skillings (1814–1894). His younger sister was Susan Willard Flint (1838–1869), who married Brevet Major C. Grover. His aunts included Mrs. Susan Willard Jewett and Mrs. Elizabeth Henshaw Thiverick. He attended medical lectures at the University of Louisville from 1854 to 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surgeon-General
Surgeon general (: surgeons general) is a title used in several Commonwealth countries and most NATO nations to refer either to a senior military medical officer or to a senior uniformed physician commissioned by the government and entrusted with public health responsibilities. The title originated in the 17th century, as military units acquired their own physicians. In the United Kingdom, the Surgeon General is the professional head of the military medical services and carries the rank of rear admiral, major general, or air vice marshal. In the United States, the chief public health officer is the Surgeon General of the United States, and a small number of states have state surgeons general. Moreover, three of the U.S. military services have their own surgeon general, namely the Surgeon General of the United States Army, Surgeon General of the United States Navy, and Surgeon General of the United States Air Force. See also * Chief Medical Officer (Ireland) * Chief Medic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zebra
Zebras (, ) (subgenus ''Hippotigris'') are African equines with distinctive black-and-white striped coats. There are three living species: Grévy's zebra (''Equus grevyi''), the plains zebra (''E. quagga''), and the mountain zebra (''E. zebra''). Zebras share the genus '' Equus'' with horses and asses, the three groups being the only living members of the family Equidae. Zebra stripes come in different patterns, unique to each individual. Several theories have been proposed for the function of these patterns, with most evidence supporting them as a deterrent for biting flies. Zebras inhabit eastern and southern Africa and can be found in a variety of habitats such as savannahs, grasslands, woodlands, shrublands, and mountainous areas. Zebras are primarily grazers and can subsist on lower-quality vegetation. They are preyed on mainly by lions, and typically flee when threatened but also bite and kick. Zebra species differ in social behaviour, with plains and mountain z ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stallion (horse)
A stallion is an adult male horse that has not been gelded (Neutering, castrated). Stallions follow the horse conformation, conformation and phenotype of their Horse breed, breed, but within that standard, the presence of hormones such as testosterone may give stallions a thicker, "cresty" neck, as well as a somewhat more muscular physique as compared to female horses, known as ''mares'', and castrated males, called ''geldings''. Temperament varies widely based on genetics and horse training, training, but because of their instincts as herd animals, they may be prone to aggressive behavior, particularly toward other stallions, and thus require careful management by knowledgeable handlers. With proper training and management, stallions are effective equine athletes at the highest levels of many disciplines, including horse racing, horse shows, and international Equestrian at the Summer Olympics, Olympic competition. "Stallion" is also used to refer to males of other equids, incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quagga
The quagga ( or ) (''Equus quagga quagga'') is an extinct subspecies of the plains zebra that was endemic to South Africa until it was hunted to extinction in the late 19th century. It was long thought to be a distinct species, but mtDNA studies have supported it being a subspecies of plains zebra. A more recent study suggested that it was the southernmost cline or ecotype of the species. The quagga is believed to have been around long and tall at the shoulders. It was distinguished from other zebras by its limited pattern of primarily brown and white stripes, mainly on the front part of the body. The rear was brown and without stripes, and appeared more horse-like. The distribution of stripes varied considerably between individuals. Little is known about the quagga's behaviour, but it may have gathered into herds of 30–50. Quaggas were said to be wild and lively, yet were also considered more docile than the related Burchell's zebra. They were once found in great num ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mare (horse)
A mare is an adult female horse or other equine. In most cases, a mare is a female horse over the age of three, and a filly is a female horse three and younger. In Thoroughbred horse racing, a mare is defined as a female horse more than four years old. The word can also be used for other female equine animals, particularly mules and zebras, but a female donkey is usually called a "jenny". A ''broodmare'' is a mare used for breeding. Reproductive cycle Mares carry their young (called foals) for approximately 11 months from conception to birth, the average range being 320–370 days.Ensminger, M. E. ''Horses and Horsemanship: Animal Agriculture Series.'' Sixth Edition. Interstate Publishers, 1990. p. 156 Usually just one young is born; twins are rare. When a domesticated mare foals, she nurses the foal for at least four to six months before it is weaned, though mares in the wild may allow a foal to nurse for up to a year. The estrous cycle, also known as "season" or " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Variation Of Animals And Plants Under Domestication
''The Variation of Animals and Plants Under Domestication'' is a book by Charles Darwin that was first published in January 1868. A large proportion of the book contains detailed information on the domestication of animals and plants but it also contains in Chapter XXVII a description of Darwin's theory of heredity which he called pangenesis. Background Darwin had been working for two years writing his "big book", provisionally titled ''Natural Selection (manuscript), Natural Selection'', when on 18 June 1858 he received a parcel from Alfred Wallace, who was then living in Borneo. It enclosed a twenty pages manuscript describing an evolutionary mechanism that was similar to Darwin's own theory. Under pressure to publish his ideas, Darwin started work on an "Abstract (summary), abstract" summary, which was published in November 1859 as ''On the Origin of Species''. In the introduction he announced that in a future publication he hoped to give "in detail all the facts, with ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
