|
1868 In Science
The year 1868 in science and technology involved some significant events, listed below. Biology * January 30 – Publication of Charles Darwin's ''The Variation of Animals and Plants Under Domestication'' (by John Murray in London), including his theory of heredity, which he calls pangenesis. * Jules-Emile Planchon and colleagues propose ''Phylloxera'' as the cause of the Great French Wine Blight. * Roland Trimen reads a paper to the Linnaean Society explaining Batesian mimicry in African butterflies. * T. H. Huxley discovers what he thinks is primordial matter and names it '' Bathybius haeckelii''. He admits his mistake in 1871. * The Granny Smith apple cultivar originates in Eastwood, New South Wales, Australia, from a chance seedling propagated by Maria Ann Smith (née Sherwood, 1799–1870). Chemistry * August 18 – The element later named as helium is first detected in the spectrum of the Sun's chromosphere by French astronomer Jules Janssen during a total eclipse in G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science
Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for scientific reasoning is tens of thousands of years old. The earliest written records in the history of science come from Ancient Egypt and Mesopotamia in around 3000 to 1200 BCE. Their contributions to mathematics, astronomy, and medicine entered and shaped Greek natural philosophy of classical antiquity, whereby formal attempts were made to provide explanations of events in the physical world based on natural causes. After the fall of the Western Roman Empire, knowledge of Greek conceptions of the world deteriorated in Western Europe during the early centuries (400 to 1000 CE) of the Middle Ages, but was preserved in the Muslim world during the Islamic Golden Age and later by the efforts of Byzantine Greek scholars who brought Greek ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 stories regarding Huxley's famous 1860 Oxford evolution debate with Samuel Wilberforce were a key moment in the wider acceptance of evolution and in his own career, although some historians think that the surviving story of the debate is a later fabrication. Huxley had been planning to leave Oxford on the previous day, but, after an encounter with Robert Chambers, the author of '' Vestiges'', he changed his mind and decided to join the debate. Wilberforce was coached by Richard Owen, against whom Huxley also debated about whether humans were closely related to apes. Huxley was slow to accept some of Darwin's ideas, such as gradualism, and was undecided about natural selection, but despite this he was wholehearted in his public support of Darw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
French People
The French people (french: Français) are an ethnic group and nation primarily located in Western Europe that share a common French culture, history, and language, identified with the country of France. The French people, especially the native speakers of langues d'oïl from northern and central France, are primarily the descendants of Gauls (including the Belgae) and Romans (or Gallo-Romans, western European Celtic and Italic peoples), as well as Germanic peoples such as the Franks, the Visigoths, the Suebi and the Burgundians who settled in Gaul from east of the Rhine after the fall of the Roman Empire, as well as various later waves of lower-level irregular migration that have continued to the present day. The Norse also settled in Normandy in the 10th century and contributed significantly to the ancestry of the Normans. Furthermore, regional ethnic minorities also exist within France that have distinct lineages, languages and cultures such as Bretons in Brittany, Occi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosphere
A chromosphere ("sphere of color") is the second layer of a star's atmosphere, located above the photosphere and below the solar transition region and corona. The term usually refers to the Sun's chromosphere, but not exclusively. In the Sun's atmosphere, the chromosphere is roughly in height, or slightly more than 1% of the Sun's radius at maximum thickness. It possesses a homogeneous layer at the boundary with the photosphere. Hair-like jets of plasma, called spicules, rise from this homogeneous region and through the chromosphere, extending up to into the corona above. The chromosphere has a characteristic red color due to electromagnetic emissions in the ''H''α spectral line. Information about the chromosphere is primarily obtained by analysis of its emitted electromagnetic radiation. Chromospheres have also been observed on stars other than the Sun. On large stars, chromospheres sometimes make up a significant proportion of the entire star. For example, the chro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emission Spectrum
The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an electron making a atomic electron transition, transition from a high energy state to a lower energy state. The photon energy of the emitted photon is equal to the energy difference between the two states. There are many possible electron transitions for each atom, and each transition has a specific energy difference. This collection of different transitions, leading to different radiated wavelengths, make up an emission spectrum. Each element's emission spectrum is unique. Therefore, spectroscopy can be used to identify elements in matter of unknown composition. Similarly, the emission spectra of molecules can be used in chemical analysis of substances. Emission In physics, emission is the process by which a higher energy quantum mechanical state of a particle becomes converted to a lower one through the emission of a photon, resulting in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helium
Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling and melting point are the lowest among all the elements. It is the second lightest and second most abundant element in the observable universe (hydrogen is the lightest and most abundant). It is present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this in both the Sun and in Jupiter, due to the very high nuclear binding energy (per nucleon) of helium-4, with respect to the next three elements after helium. This helium-4 binding energy also accounts for why it is a product of both nuclear fusion and radioactive decay. The most common isotope of helium in the universe is helium-4, the vast majority of which was formed during t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Dictionary Of Biography
The ''Australian Dictionary of Biography'' (ADB or AuDB) is a national co-operative enterprise founded and maintained by the Australian National University (ANU) to produce authoritative biographical articles on eminent people in Australia's history. Initially published in a series of twelve hard-copy volumes between 1966 and 2005, the dictionary has been published online since 2006 by the National Centre of Biography at ANU, which has also published ''Obituaries Australia'' (OA) since 2010. History The ADB project has been operating since 1957. Staff are located at the National Centre of Biography in the History Department of the Research School of Social Sciences at the Australian National University. Since its inception, 4,000 authors have contributed to the ADB and its published volumes contain 9,800 scholarly articles on 12,000 individuals. 210 of these are of Indigenous Australians, which has been explained by Bill Stanner's "cult of forgetfulness" theory around the co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fruit Tree Propagation
Fruit tree propagation is usually carried out vegetatively (non-sexually) by grafting or budding a desired variety onto a suitable rootstock. Perennial plants can be propagated either by sexual or vegetative means. Sexual reproduction begins when a male germ cell ( pollen) from one flower fertilises a female germ cell (ovule, incipient seed) of the same species, initiating the development of a fruit containing seeds. Each seed, when germinated, can grow to become a new specimen tree. However, the new tree inherits characteristics of both its parents, and it will not grow true to the variety of either parent from which it came. That is, it will be a fresh individual with an unpredictable combination of characteristics of its own. Although this is desirable in terms of producing novel combinations from the richness of the gene pool of the two parent plants (such sexual recombination is the source of new cultivars), only rarely will the resulting new fruit tree be directly useful o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chance Seedling
A chance seedling is a plant that is the product of unintentional breeding. Identifying the parent plants of a chance seedling may be difficult. It may be necessary to genetically analyse the seedling and surrounding plants to be sure. Plants that come from the artificial union of gametes from a maternal and paternal source are not chance seedlings. A chance seedling may be a genetically unique individual with desirable characteristics that is then intentionally bred. The Kindred Spirit Hybrid Oak and the Granny Smith, Wolf River, Lady Alice, Red Delicious, Gravenstein, Braeburn, Samarbehisht Chausa, Calville Blanc d'hiver, Belle de Boskoop and Baldwin apples are examples of varieties that started with chance seedlings that were selected and assigned cultivar status owing to their desirable properties. See also *Volunteer (botany) In gardening and agronomic terminology, a volunteer is a plant that grows on its own, rather than being deliberately planted by a farmer or gardener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, smaller islands. With an area of , Australia is the largest country by area in Oceania and the world's List of countries and dependencies by area, sixth-largest country. Australia is the oldest, flattest, and driest inhabited continent, with the least fertile soils. It is a Megadiverse countries, megadiverse country, and its size gives it a wide variety of landscapes and climates, with Deserts of Australia, deserts in the centre, tropical Forests of Australia, rainforests in the north-east, and List of mountains in Australia, mountain ranges in the south-east. The ancestors of Aboriginal Australians began arriving from south east Asia approximately Early human migrations#Nearby Oceania, 65,000 years ago, during the Last Glacial Period, last i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eastwood, New South Wales
Eastwood is a suburb of Sydney, Australia. Eastwood is located 17 kilometres north-west of the Sydney central business district in the local government areas of the City of Ryde and the City of Parramatta. Eastwood is in the Northern Sydney region. Originally thought to have been inhabited by the Wallumedegal Aboriginal tribe, who lived in the area between the Lane Cove and Parramatta Rivers, the area was first settled by Europeans shortly after the arrival of the First Fleet in 1788, from land grants to Royal Marines and New South Wales Corps, and was named "Eastwood" by an early Irish free settler, William Rutledge. Today it is a large suburban centre in the north of Sydney of over 17,000 people, with a large shopping area. Eastwood has a large population of Asian descent with immigrants from China and South Korea transforming the commercial precinct in the past decade. Eastwood is famous for the Granny Smith apple, accidentally first grown in the suburb by Maria Ann Sm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cultivar
A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, or carefully controlled seed production. Most cultivars arise from purposeful human manipulation, but some originate from wild plants that have distinctive characteristics. Cultivar names are chosen according to rules of the International Code of Nomenclature for Cultivated Plants (ICNCP), and not all cultivated plants qualify as cultivars. Horticulturists generally believe the word ''cultivar''''Cultivar'' () has two meanings, as explained in ''Formal definition'': it is a classification category and a taxonomic unit within the category. When referring to a taxon, the word does not apply to an individual plant but to all plants that share the unique characteristics that define the cultivar. was coined as a term meaning "cultivated variety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Cultivar")