Aleeta curvicosta, commonly called the floury baker or floury miller, is a species of cicada native to the eastern coastline of Australia. Described in 1834 by Ernst Friedrich Germar, it is currently the only described species in the genus Aleeta. The floury baker's distinctive appearance and loud call make it popular with children. Both the common and genus name are derived from the white, flour-like filaments covering the adult body. Its body and eyes are generally brown with pale patterns. Its forewings have dark brown patches at the base of two of their apical cells. The female is larger than the male, and both grow larger in regions of higher rainfall. The male has a loud and complex call generated by the frequent buckling of ribbed tymbals and amplified by abdominal air sacs. The floury baker is solitary and occurs in low densities. Individuals emerge from the soil between November and February, and can be seen until May. They inhabit a variety of trees, with a preference for paperbark. The floury baker, which is a relatively poor flier, is preyed upon bycicada killer wasps and a wide variety of birds, and can succumb to a cicada-specific fungal disease. (Full article...)
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The oceangoing (anadromous) form, including those returning for spawning, are known as steelhead in Canada and the U.S.[27] In Tasmania they are commercially propagated in sea cages and are known as ocean trout, although they are the same species.[28]
Like salmon, steelhead return to their original hatching grounds to spawn. Similar to Atlantic salmon, but unlike their Pacific Oncorhynchus salmonid kin, steelhead are iteroparous (able to spawn several times, each time separated by months) and make several spawning trips between fresh and salt water, although fewer than 10 percent of native spawning adults survive from one spawning to another.[29] The survival rate for introduced populations in the Great Lakes is as high as 70 percent. As young steelhead transition from freshwater to saltwater, a process called "smoltification" occurs where the trout undergoes physiological changes to allow it to survive in sea water.[30] There are genetic differences between freshwater and steelhead populations that may account for the smoltification in steelheads.[31]
Juvenile steelhead may remain in the river for one to three years before smolting and migrating to sea. Individual steelhead populations leave the ocean and migrate into their freshwater spawning tributaries at different times of the year. Two general forms exist—"summer-run steelhead" and "winter-run steelhead". Summer-run fish leave the ocean between May and October, before their reproductive organs are fully mature. They mature in fresh water while en route to spawning grounds where they spawn in the spring. Summer-run fish generally spawn in longer, more inland rivers such as the Columbia River. Winter-run fish are ready to spawn when they leave the ocean, typically between November and April, and spawn shortly after returning to fresh water. Winter-run fish generally spawn in shorter, coastal rivers typically found along the Olympic Peninsula and British Columbia coastline,[21]and summer-run fish are found in some shorter, coastal streams.[32] Once steelhead enter riverine systems and reach suitable spawning grounds, they spawn just like resident freshwater rainbow trout.[21]
Freshwater resident rainbow trout usually inhabit and spawn in small to moderately large, well oxygenated, shallow rivers with gravelbottoms. They are native to the alluvial or freestone streams that are typical tributaries of the Pacific basin, but introduced rainbow trout have established wild, self-sustaining populations in other river types such as bedrock and spring creeks. Lake resident rainbow trout are usually found in moderately deep, cool lakes with adequate shallows and vegetation to support production of sufficient food sources. Lake populations generally require access to gravelly bottomed streams to be self-sustaining.[23]
Spawning sites are usually a bed of fine gravel in a riffle above a pool. A female trout clears a redd in the gravel by turning on her side and beating her tail up and down. Female rainbow trout usually produce 2000 to 3000 4-to-5-millimetre (0.16 to 0.20 in) eggs per kilogram of weight.[24] During spawning, the eggs fall into spaces between the gravel, and immediately the female begins digging at the upstream edge of the nest, covering the eggs with the displaced gravel. As eggs are released by the female, a male moves alongside and deposits milt (sperm) over the eggs to fertilize them. The eggs usually hatch in about four to seven weeks although the time of hatching varies greatly with region and habitat. Newly hatched trout are called sac-fry or alevin. In approximately two weeks, the yolk sac is completely consumed and fry commence feeding mainly on zooplankton. The growth rate of rainbow trout is variable with area, habitat, life history and quality and quantity of food.[25] As fry grow, they begin to develop "parr" marks or dark vertical bars on their sides. In this juvenile stage, immature trout are often called "parr" because of the marks. These small juvenile trout are sometimes called fingerlings because they are approximately the size of a human finger. In streams where rainbow trout are stocked for sport fishing but no natural reproduction occurs, some of the stocked trout may survive and grow or "carryover" for several seasons before they are caught or perish.[26]
Resident freshwater rainbow trout adults average between 1 and 5 lb (0.45 and 2.27 kg) in riverine environments, while lake-dwelling and anadromous forms may reach 20 lb (9.1 kg). Coloration varies widely between regions and subspecies. Adult freshwater forms are generally blue-green or olive green with heavy black spotting over the length of the body. Adult fish have a broad reddish stripe along the lateral line, from gills to the tail, which is most pronounced in breeding males.[9] The caudal fin is squarish and only mildly forked. Lake-dwelling and anadromous forms are usually more silvery in color with the reddish stripe almost completely gone. Juvenile rainbow trout display parr marks (dark vertical bars) typical of most salmonid juveniles. In some redband and golden trout forms parr marks are typically retained into adulthood.[17] Some coastal rainbow trout (O. m. irideus) and Columbia River redband trout (O. m. gairdneri)populations and cutbow hybrids may also display reddish or pink throat markings similar to cutthroat trout.[18] In many jurisdictions, hatchery-bred trout can be distinguished from native trout via fin clips,[19] typically placed on the adipose fin.[20]
Life cycle[edit]
Rainbow trout, including steelhead forms, generally spawn in early to late spring (January to June in the Northern Hemisphere and September to November in the Southern Hemisphere) when water temperatures reach at least 42 to 44 °F (6 to 7 °C).[21] The maximum recorded lifespan for a rainbow trout is 11 years.[22]
The scientific name of the rainbow trout is Oncorhynchus mykiss.[3] The species was originally named by German naturalist andtaxonomist Johann Julius Walbaum in 1792 based on type specimens from the Kamchatka Peninsula in Siberia. Walbaum's original species name, mykiss, was derived from the local Kamchatkan name used for the fish, mykizha. The name of the genus is from theGreek onkos ("hook") and rynchos ("nose"), in reference to the hooked jaws of males in the mating season (the "kype").[4]
Sir John Richardson, a Scottish naturalist, named a specimen of this species Salmo gairdneri in 1836 to honor Meredith Gairdner, aHudson's Bay Company surgeon at Fort Vancouver on the Columbia River who provided Richardson with specimens.[5] In 1855, William P. Gibbons, the curator of Geology and Mineralogy[6] at the California Academy of Sciences, found a population and named itSalmo iridia (Latin: rainbow), later corrected to Salmo irideus. These names faded once it was determined that Walbaum's description of type specimens was conspecific and therefore had precedence.[7] In 1989, morphological and genetic studies indicated that trout of thePacific basin were genetically closer to Pacific salmon (Oncorhynchus species) than to the Salmos – brown trout (Salmo trutta) orAtlantic salmon (Salmo salar) of the Atlantic basin.[8] Thus, in 1989, taxonomic authorities moved the rainbow, cutthroat and other Pacific basin trout into the genus Oncorhynchus.[4] Walbaum's name had precedence, so the species name Oncorhynchus mykissbecame the scientific name of the rainbow trout. The previous species names irideus and gairdneri were adopted as subspecies names for the coastal rainbow and Columbia River redband trout, respectively.[4] Anadromous forms of the coastal rainbow trout (O. m. irideus)or redband trout (O. m. gairdneri) are commonly known as steelhead.[3]
The rainbow trout (Oncorhynchus mykiss) is a species of salmonid native to cold-watertributaries of the Pacific Ocean in Asia and North America. The steelhead (sometimes "steelhead trout") is an anadromous (sea-run) form of the coastal rainbow trout (O. m. irideus)or Columbia River redband trout (O. m. gairdneri) that usually returns to fresh water to spawnafter living two to three years in the ocean. Freshwater forms that have been introduced into the Great Lakes and migrate into tributaries to spawn are also called steelhead.
Adult freshwater stream rainbow trout average between 1 and 5 lb (0.5 and 2.3 kg), while lake-dwelling and anadromous forms may reach 20 lb (9.1 kg). Coloration varies widely based on subspecies, forms and habitat. Adult fish are distinguished by a broad reddish stripe along the lateral line, from gills to the tail, which is most vivid in breeding males.
Wild-caught and hatchery-reared forms of this species have been transplanted and introduced for food or sport in at least 45 countries and every continent except Antarctica. Introductions to locations outside their native range in the United States (U.S.), Southern Europe, Australia and South America have damaged native fish species. Introduced populations may impact native species by preying on them, out-competing them, transmitting contagious diseases (such as whirling disease), or hybridizing with closely related species and subspecies, thus reducing genetic purity. Other introductions into waters previously devoid of any fish species or with severely depleted stocks of native fish have created world-class sport fisheries such as the Great Lakes and Wyoming's Firehole River.
Some local populations of specific subspecies, or in the case of steelhead, distinct population segments, are listed as either threatened or endangered under the Endangered Species Act. The steelhead is the official state fish of Washington.[2]
Contemporary almanacs[edit]
Currently published almanacs such as Whitaker's Almanack have expanded their scope and contents beyond that of their historical counterparts. Modern almanacs include a comprehensive presentation of statistical and descriptive data covering the entire world. Contents also include discussions of topical developments and a summary of recent historical events. Other currently published almanacs (ca. 2006) include TIME Almanac with Information Please, World Almanac and Book of Facts, The Farmer's Almanac andThe Old Farmer's Almanac. In 2007, Harrowsmith Country Life Magazine launched a Canadian Almanac, written in Canada, with all-Canadian content.
Major topics covered by almanacs (reflected by their tables of contents) include: geography, government, demographics, agriculture,economics and business, health and medicine, religion, mass media, transportation, science and technology, sport, and awards/prizes.
Other examples include The Almanac of American Politics published by the National Journal, The Almanac of American Literature, andThe Almanac of British Politics.
From 1985 to 1990, approximately 53% of all almanac sales sold in the United States were sold through the "Where in the World Is Carmen Sandiego? (1985)" computer game pack that included a complimentary World Almanac and Book of Facts.
GPS almanac[edit]
The GPS almanac, as part of the data transmitted by each GPS satellite, contains coarse orbit and status information for all satellites in the constellation, an ionospheric model, and information to relate GPS derived time to Coordinated Universal Time (UTC). Hence the GPS almanac provide a similar goal as the ancient Babylonian almanac, to find celestial bodies.
Early modern almanacs[edit]
By the second half of the 16th century, yearly almanacs were being produced in English by men such as Anthony Askham, Thomas Buckminster, John Dade and Gabriel Frende. In the 17th century, English almanacs were bestsellers, second only to the Bible; by the middle of the century, 400,000 almanacs were being produced annually (a complete listing can be found in the English Short Title Catalogue). Until its deregulation in 1775, the Stationers' Company maintained a lucrative monopoly over almanac publication in England.[12] Richard Allestree (who is not the same as thisRichard Allestree) wrote one of the more popular English almanacs, producing yearly volumes from 1617 to 1643, but his is by no means the earliest or the longest-running almanac.
In British America, William Pierce of Harvard College published the first American almanac entitled, An Almanac for New England for the year 1639 Cambridge, Massachusetts. Harvard became the first center for the annual publication of almanacs with various editors including Samuel Danforth, Oakes, Cheever, Chauncey, Dudley, Foster, et alia. An almanac maker going under the pseudonym of Poor Richard, Knight of the Burnt Island began to publish Poor Robin's Almanack one of the first comic almanacs that parodied these horoscopes in its 1664 issue, saying "This month we may expect to hear of the Death of some Man, Woman, or Child, either in Kent or Christendom." Other noteworthy comic almanacs include those published from 1687-1702 by John Tully of Saybrook, Connecticut.
The most important early American almanacs were made from 1726-1775 by Nathaniel Ames of Dedham, Massachusetts. A few years later James Franklin began publishing the Rhode-Island Almanack beginning in 1728. Five years later his brother Benjamin Franklin began publishing Poor Richard's Almanack from 1733-1758. Benjamin Banneker improved on the Almanac from 1792-1797.
Ephemerides, zijs and tables[edit]
The origins of the almanac can be connected to ancient Babylonian astronomy, when tables of planetary periods were produced in order to predict lunar and planetary phenomena.[10] Similar treatises called Zij were later composed in medieval Islamic astronomy. The modern almanac differs from Babylonian, Ptolemaic and Zij tables in the sense that "the entries found in the almanacs give directly the positions of the celestial bodies and need no further computation", in contrast to the more common "auxiliary astronomical tables" based on Ptolemy's Almagest. The earliest known almanac in this modern sense is the Almanac of Azarqueil written in 1088 by Abū Ishāq Ibrāhīm al-Zarqālī (Latinized as Arzachel) in Toledo, al-Andalus. The work provided the true daily positions of the sun, moon and planets for four years from 1088 to 1092, as well as many other related tables. A Latin translation and adaptation of the work appeared as the Tables of Toledo in the 12th century and the Alfonsine tables in the 13th century.[11][verification needed]
Medieval almanacs[edit]
After almanacs were devised, people still saw little difference between predicting the movements of the stars and tides, and predicting the future in the divination sense. Early almanacs therefore contained general horoscopes, as well as the more concrete information. In 1150 Solomon Jarchus created such an almanac considered to be among the first modern almanacs. Copies of 12th century almanacs are found in the British Museum, and in the Universities of Oxford and Cambridge. In 1300, Petrus de Dacia created an almanac (Savilian Library, Oxford). This was the same year Roger Bacon, OFM, produced his as well. In 1327 Walter de Elvendene created an almanac and later on John Somers of Oxford, in 1380. In 1386 Nicholas de Lynne, Oxford produced an almanac. In 1457 the first printed almanac was published at Mainz, by Gutenberg (eight years before the famous Bible). Regio-Montanus produced an almanac in 1472 (Nuremberg, 1472), which was continued in print for several centuries in many editions. In 1497 the Sheapheard’s Kalendar, translated from French (Richard Pynson) became the first English printed almanac.
An almanac is text listing a set of events forthcoming in the next year. A calendar, which is a system for time keeping, in written form is usually produced as a most simple almanac: it includes additional information about the day of the week on which a particular day falls, major holidays, the phases of the moon etc. The set of events noted in an almanac are selected in view of a more or less specific readers e.g. farmers, sailors, astronomers or others.
Hemerologies and parapegmata[edit]
The earlier texts considered to be almanacs have been found in the Near east, dating back to the middle of the second millennium BCE. They have been called generally hemerologies, from the Greek 'hēmerā', meaning 'day'. Among them is the so-called Babylonian Almanac, which lists favorable and unfavorable days with advice on what to do on each of them. Successive variants and versions aimed at different readership have been found.[4] Egyptians lists for good and bad moments, three times each day, have also been found. It is not really known how these prognostics were produced but they seem invariably connected with celestial events.[5][6] The flooding of the Nile valley, a most important event in ancient Egypt, was expected to occur at the summer solstice but as the civil calendar had exactly 365 days, over the centuries the date was drifting in the calendar.[7] The first heliacal rising of Sirius was used for its prediction and this practice, the observation of some star and its connecting to some event apparently spread.
The Greek almanac, known as parapegma, has existed in the form an inscribed stone on which the days of the month were indicated by movable pegs inserted into bored holes, hence the name. There were also written texts and according to Diogenes Laërtius, Parapegmawas the title of a book by Democritus.[8] Ptolemy, the Alexandrian astronomer (2nd century) wrote a treatise, Phaseis—"phases of fixed stars and collection of weather-changes" is the translation of its full title—the core of which is a parapegma, a list of dates of seasonally regular weather changes, first appearances and last appearances of stars or constellations at sunrise or sunset, and solar events such as solstices, all organized according to the solar year. With the astronomical computations were expected weather phenomena, composed as a digest of observations made by various authorities of the past. Parapegmata had been composed for centuries.
Ptolemy believed that astronomical phenomena caused the changes in seasonal weather; his explanation of why there was not an exact correlation of these events was that the physical influences of other heavenly bodies also came into play. Hence for him, weather prediction was a special division of astrology.[9]
The etymology of the word is unclear, but there are several theories:
- The word almanac derives from the Greek word almenichiaka, which means calendar. The earliest almanacs were calendars that included agricultural, astronomical, or meteorological data.
- One suggestion is that alamanac was originally an Arabic word, al-manākh, meaning the climate, this refers to the natural change in weather. In the modern sense too an almanac, or almanakh, is the average weather forecast for a certain period of time that is characterized by relatively stable weather conditions covering a specific area, also called climate.
- However, the earliest documented use of the word in any language is in Latin in 1267 by Roger Bacon, where it meant a set of tables detailing movements of heavenly bodies including the moon.
- One etymology report says: "The ultimate source of the word is obscure. Its first syllable, al-, and its general relevance to medieval science and technology, strongly suggest an Arabic origin, but no convincing candidate has been found."[1]
- Another report similarly says of Almanac: "First seen in Roger Bacon. Apparently from Spanish Arabic, al-manakh, but this is not an Arabic word [interpret: this is not a word found in Arabic texts]....The word remains a puzzle."[2]
- The New English Dictionary on Historical Principles similarly says "the word has no etymon in Arabic" but indirect circumstantial evidence "points to a Spanish Arabic al-manākh".[3]
The reason why the proposed Arabic word is speculatively spelled al-manākh is that the spelling occurred as "almanach" as well as almanac (and Roger Bacon used both spellings). The earliest use of the word was in the context of astronomy calendars.
The prestige of the Tables of Toledo and other medieval Arabic astronomy works at the time of the word's emergence in the West, together with the absence of the word in Arabic, suggest it may have been invented in the West, and is pseudo-Arabic. At that time in the West, it would have been prestigious to attach an Arabic appellation to a set of astronomical tables. Also around that time, prompted by that motive, the Latin writer Pseudo-Geber wrote under an Arabic pseudonym. (The later alchemy word alkahest is known to be pseudo-Arabic.)
The Gulf of Thailand harbours many coral reefs, and thus several diving resorts. Due to the tropical warmth of the water, it is popular with tourists. Some of the most important tourist destinations in the Gulf of Thailand are the islands of Ko Samui and Ko Pha Ngan in Surat Thani Province, Pattaya in Chonburi Province, Cha-Am in Phetchaburi Province, Hua Hin in Prachuap Khiri Khan Province, Ko Samet inRayong Province, and Ko Chang in Trat Province
Ko Tao is a center of the diving tourism.
Territorial disputes[edit]
There are territorial disputes in the area between Malaysia, Thailand, Cambodia and Vietnam.
- Malaysia and Thailand in particular have chosen to jointly develop the disputed areas, which include the islands of Ko Kra and Ko Losin.[citation needed]
- A long-standing dispute between Cambodia and Vietnam in the Gulf of Siam concerns mainly the island of Phú Quốc or Koh Tral in Khmer, which is located off the Cambodian coast.[4] Cambodia also claims 48,000 km2 of shelf area.[5]
See also[edit]
References[edit]
- ^ "ระยะทางเสด็จฯ ประพาสชายทะเลอ่าวสยาม พ.ศ. 2470" [A report on the royal travel through the Gulf of Siam, 1927] (pdf). Royal Thai Government Gazette (in Thai) (Bangkok: Cabinet Secretariat) 88 (D): 44. 1927-05-22. Retrieved 2014-03-08.
- ^ Proceedings of the Royal Geographical Society
- ^ "Limits of Oceans and Seas, 3rd edition". International Hydrographic Organization. 1953. Retrieved 7 February 2010.
- ^ John Robert Victor Prescott, Boundaries and frontiers
- ^ Paul Ganster & David E. Lorey, Borders and border politics in a globalizing world.
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