Pakistan the Islamic Republic of Pakistan, is a country in South Asia. It is the world’s sixth-most populous country with a population exceeding 212,742,631 people. In area, it is the 33rd-largest country. Pakistan has a 1,046-kilometre coastline along the Arabian Sea and Gulf of Oman in the south and is bordered by India to the east, Afghanistan to the west, Iran to the southwest, China in the far northeast, it is separated narrowly from Tajikistan by Afghanistan's Wakhan Corridor in the northwest, shares a maritime border with Oman. The territory that now constitutes Pakistan was the site of several ancient cultures and intertwined with the history of the broader Indian subcontinent; the ancient history involves the Neolithic site of Mehrgarh and the Bronze Age Indus Valley Civilisation, was home to kingdoms ruled by people of different faiths and cultures, including Hindus, Indo-Greeks, Turco-Mongols and Sikhs. The area has been ruled by numerous empires and dynasties, including the Persian Achaemenid Empire, Alexander III of Macedon, the Seleucid Empire, the Indian Maurya Empire, the Gupta Empire, the Arab Umayyad Caliphate, the Delhi Sultanate, the Mongol Empire, the Mughal Empire, the Afghan Durrani Empire, the Sikh Empire and, most the British Empire.
Pakistan is the only country to have been created in the name of Islam. It is an ethnically and linguistically diverse country, with a diverse geography and wildlife. A dominion, Pakistan adopted a constitution in 1956, becoming an Islamic republic. An ethnic civil war and Indian military intervention in 1971 resulted in the secession of East Pakistan as the new country of Bangladesh. In 1973, Pakistan adopted a new constitution which stipulated that all laws are to conform to the injunctions of Islam as laid down in the Quran and Sunnah. A regional and middle power, Pakistan has the sixth-largest standing armed forces in the world and is a nuclear power as well as a declared nuclear-weapons state, the second in South Asia and the only nation in the Muslim world to have that status. Pakistan has a semi-industrialised economy with a well-integrated agriculture sector and a growing services sector, it is ranked among the emerging and growth-leading economies of the world, is backed by one of the world's largest and fastest-growing middle class.
Pakistan's political history since independence has been characterized by periods of military rule, political instability and conflicts with India. The country continues to face challenging problems, including overpopulation, poverty and corruption. Pakistan is a member of the UN, the Shanghai Cooperation Organisation, the OIC, the Commonwealth of Nations, the SAARC and the Islamic Military Counter Terrorism Coalition; the name Pakistan means "land of the pure" in Urdu and Persian. It alludes to the word pāk meaning pure in Pashto; the suffix ـستان is a Persian word meaning the place of, recalls the synonymous Sanskrit word sthāna स्थान. The name of the country was coined in 1933 as Pakstan by Choudhry Rahmat Ali, a Pakistan Movement activist, who published it in his pamphlet Now or Never, using it as an acronym referring to the names of the five northern regions of British India: Punjab, Kashmir and Baluchistan; the letter i was incorporated to ease pronunciation. Some of the earliest ancient human civilisations in South Asia originated from areas encompassing present-day Pakistan.
The earliest known inhabitants in the region were Soanian during the Lower Paleolithic, of whom stone tools have been found in the Soan Valley of Punjab. The Indus region, which covers most of present day Pakistan, was the site of several successive ancient cultures including the Neolithic Mehrgarh and the Bronze Age Indus Valley Civilisation at Harappa and Mohenjo-Daro; the Vedic period was characterised by an Indo-Aryan culture. Multan was an important Hindu pilgrimage centre; the Vedic civilisation flourished in the ancient Gandhāran city of Takṣaśilā, now Taxila in the Punjab, founded around 1000 BCE. Successive ancient empires and kingdoms ruled the region: the Persian Achaemenid Empire, Alexander the Great's empire in 326 BCE and the Maurya Empire, founded by Chandragupta Maurya and extended by Ashoka the Great, until 185 BCE; the Indo-Greek Kingdom founded by Demetrius of Bactria included Gandhara and Punjab and reached its greatest extent under Menander, prospering the Greco-Buddhist culture in the region.
Taxila had one of the earliest universities and centres of higher education in the world, established during the late Vedic period in 6th century BCE. The school consisted of several monasteries without large dormitories or lecture halls where the religious instruction was provided on an individualistic basis; the ancient university was documented by the invading forces of Alexander the Great, "the like of which had not been seen in Greece," and was recorded by Chinese pilgrims in the 4th or 5th century CE. At its zenith, the Rai Dynasty of Sindh ruled the surrounding territories; the Pala Dynasty was the last Buddhist empire, under Dharmapala and Devapala, stretched across South Asia from what is now Bangladesh through Northern India to Pakistan. The Arab conqueror Muhammad bin Qasim conquered Sindh in 711 CE; the Pakistan government's official chronol
Indonesia the Republic of Indonesia, is a country in Southeast Asia, between the Indian and Pacific oceans. It is the world's largest island country, with more than seventeen thousand islands, at 1,904,569 square kilometres, the 14th largest by land area and the 7th largest in combined sea and land area. With over 261 million people, it is the world's 4th most populous country as well as the most populous Muslim-majority country. Java, the world's most populous island, is home to more than half of the country's population; the sovereign state is a constitutional republic with an elected parliament. It has 34 provinces. Jakarta, the country's capital, is the second most populous urban area in the world; the country shares land borders with Papua New Guinea, East Timor, the eastern part of Malaysia. Other neighbouring countries include Singapore, the Philippines, Australia and India's Andaman and Nicobar Islands. Despite its large population and densely populated regions, Indonesia has vast areas of wilderness that support a high level of biodiversity.
The country has abundant natural resources like oil and natural gas, tin and gold. Agriculture produces rice, palm oil, coffee, medicinal plants and rubber. Indonesia's major trading partners are China, United States, Japan and India. History of the Indonesian archipelago has been influenced by foreign powers drawn to its natural resources, it has been an important region for trade since at least the 7th century, when Srivijaya and later Majapahit traded with entities from mainland China and the Indian subcontinent. Local rulers absorbed foreign cultural and political models from the early centuries and Hindu and Buddhist kingdoms flourished. Muslim traders and Sufi scholars brought Islam, while European powers brought Christianity and fought one another to monopolise trade in the Spice Islands of Maluku during the Age of Discovery. Although sometimes interrupted by the Portuguese and British, the Dutch were the foremost European power for much of its 350-year presence in the archipelago. In early 20th century, the concept of "Indonesia" as a nation state emerged, independence movements began to take shape.
During the decolonisation of Asia after World War II, Indonesia achieved independence in 1949 following an armed and diplomatic conflict with the Netherlands. Indonesia consists of hundreds of distinct native ethnic and linguistic groups, with the largest—and politically dominant—ethnic group being the Javanese. A shared identity has developed, defined by a national language, ethnic diversity, religious pluralism within a Muslim-majority population, a history of colonialism and rebellion against it. Indonesia's national motto, "Bhinneka Tunggal Ika", articulates the diversity that shapes the country. Indonesia's economy is the world's 16th largest by nominal GDP and the 7th largest by GDP at PPP. Indonesia is a member of several multilateral organisations, including the UN, WTO, IMF and G20, it is a founding member of Non-Aligned Movement, Association of Southeast Asian Nations, Asia-Pacific Economic Cooperation, East Asia Summit, Asian Infrastructure Investment Bank and Organisation of Islamic Cooperation.
The name Indonesia derives from the Greek name of the Indos and the word nesos, meaning "Indian islands". The name dates to the 18th century, far predating the formation of independent Indonesia. In 1850, George Windsor Earl, an English ethnologist, proposed the terms Indunesians—and, his preference, Malayunesians—for the inhabitants of the "Indian Archipelago or Malayan Archipelago". In the same publication, one of his students, James Richardson Logan, used Indonesia as a synonym for Indian Archipelago. However, Dutch academics writing in East Indies publications were reluctant to use Indonesia. After 1900, Indonesia became more common in academic circles outside the Netherlands, native nationalist groups adopted it for political expression. Adolf Bastian, of the University of Berlin, popularised the name through his book Indonesien oder die Inseln des Malayischen Archipels, 1884–1894; the first native scholar to use the name was Ki Hajar Dewantara, when in 1913 he established a press bureau in the Netherlands, Indonesisch Pers-bureau.
Fossils and the remains of tools show that the Indonesian archipelago was inhabited by Homo erectus, known as "Java Man", between 1.5 million years ago and 35,000 years ago. Homo sapiens reached the region around 45,000 years ago. Austronesian peoples, who form the majority of the modern population, migrated to Southeast Asia from what is now Taiwan, they arrived around 4,000 years ago, as they spread through the archipelago, confined the indigenous Melanesians to the far eastern regions. Ideal agricultural conditions and the mastering of wet-field rice cultivation as early as the 8th century BCE allowed villages and small kingdoms to flourish by the first century CE; the archipelago's strategic sea-lane position fostered inter-island and international trade, including links with Indian kingdoms and Chinese dynasties, which were established several centuries BCE. Trade has since fundamentally shaped Indonesian history. From the 7th century CE, the powerful Srivijaya naval kingdom flourished as a result of trade and the influences of Hinduism and Buddhism that were imported with it.
Between the 8th and 10th century CE, the agricultural Buddhist Saile
In scientific nomenclature, a synonym is a scientific name that applies to a taxon that goes by a different scientific name, although the term is used somewhat differently in the zoological code of nomenclature. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies; this name is no longer in use: it is now a synonym of the current scientific name, Picea abies. Unlike synonyms in other contexts, in taxonomy a synonym is not interchangeable with the name of which it is a synonym. In taxonomy, synonyms have a different status. For any taxon with a particular circumscription and rank, only one scientific name is considered to be the correct one at any given time. A synonym cannot exist in isolation: it is always an alternative to a different scientific name. Given that the correct name of a taxon depends on the taxonomic viewpoint used a name, one taxonomist's synonym may be another taxonomist's correct name. Synonyms may arise whenever the same taxon is named more than once, independently.
They may arise when existing taxa are changed, as when two taxa are joined to become one, a species is moved to a different genus, a variety is moved to a different species, etc. Synonyms come about when the codes of nomenclature change, so that older names are no longer acceptable. To the general user of scientific names, in fields such as agriculture, ecology, general science, etc. A synonym is a name, used as the correct scientific name but, displaced by another scientific name, now regarded as correct, thus Oxford Dictionaries Online defines the term as "a taxonomic name which has the same application as another one, superseded and is no longer valid." In handbooks and general texts, it is useful to have synonyms mentioned as such after the current scientific name, so as to avoid confusion. For example, if the much advertised name change should go through and the scientific name of the fruit fly were changed to Sophophora melanogaster, it would be helpful if any mention of this name was accompanied by "".
Synonyms used in this way may not always meet the strict definitions of the term "synonym" in the formal rules of nomenclature which govern scientific names. Changes of scientific name have two causes: they may be taxonomic or nomenclatural. A name change may be caused by changes in the circumscription, position or rank of a taxon, representing a change in taxonomic, scientific insight. A name change may be due to purely nomenclatural reasons, that is, based on the rules of nomenclature. Speaking in general, name changes for nomenclatural reasons have become less frequent over time as the rules of nomenclature allow for names to be conserved, so as to promote stability of scientific names. In zoological nomenclature, codified in the International Code of Zoological Nomenclature, synonyms are different scientific names of the same taxonomic rank that pertain to that same taxon. For example, a particular species could, over time, have had two or more species-rank names published for it, while the same is applicable at higher ranks such as genera, orders, etc.
In each case, the earliest published name is called the senior synonym, while the name is the junior synonym. In the case where two names for the same taxon have been published the valid name is selected accorded to the principle of the first reviser such that, for example, of the names Strix scandiaca and Strix noctua, both published by Linnaeus in the same work at the same date for the taxon now determined to be the snowy owl, the epithet scandiaca has been selected as the valid name, with noctua becoming the junior synonym. One basic principle of zoological nomenclature is that the earliest published name, the senior synonym, by default takes precedence in naming rights and therefore, unless other restrictions interfere, must be used for the taxon. However, junior synonyms are still important to document, because if the earliest name cannot be used the next available junior synonym must be used for the taxon. For other purposes, if a researcher is interested in consulting or compiling all known information regarding a taxon, some of this may well have been published under names now regarded as outdated and so it is again useful to know a list of historic synonyms which may have been used for a given current taxon name.
Objective synonyms refer to taxa with same rank. This may be species-group taxa of the same rank with the same type specimen, genus-group taxa of the same rank with the same type species or if their type species are themselves objective synonyms, of family-group taxa with the same type genus, etc. In the case of subjective synonyms, there is no such shared type, so the synonymy is open to taxonomic judgement, meaning that th
Mauritius the Republic of Mauritius, is an island nation in the Indian Ocean. The main Island of Mauritius is located about 2,000 kilometres off the southeast coast of the African continent; the Republic of Mauritius includes the islands of Rodrigues, Agalega and St. Brandon; the capital and largest city Port Louis is located on the main island of Mauritius. In 1598, the Dutch took possession of Mauritius, they abandoned Mauritius in 1710 and the French took control of the island in 1715, renaming it Isle de France. France ceded Mauritius including all its dependencies to the United Kingdom through the Treaty of Paris, signed on 30 May 1814 and in which Réunion was returned to France; the British colony of Mauritius consisted of the main island of Mauritius along with Rodrigues, Agalega, St Brandon and the Chagos Archipelago, while the Seychelles became a separate colony in 1906. The sovereignty of Tromelin is disputed between Mauritius and France as some of the islands such as St. Brandon, Chagos and Tromelin were not mentioned in the Treaty of Paris.
In 1965, three years prior to the independence of Mauritius, the UK split the Chagos Archipelago from Mauritian territory, the islands of Aldabra and Desroches from the Seychelles, to form the British Indian Ocean Territory. The UK forcibly expelled the archipelago's local population and leased its largest island, Diego Garcia, to the United States; the UK has restricted access to the Chagos Archipelago. The sovereignty of the Chagos is disputed between Mauritius and the UK. In February 2019, in an advisory opinion given by the International Court of Justice on this dispute, the ICJ ordered the UK to hand back the Chagos Islands to Mauritius as as possible; the people of Mauritius are multiethnic and multilingual. The island's government is modelled on the Westminster parliamentary system, Mauritius is ranked for democracy and for economic and political freedom; the Human Development Index of Mauritius is one of the highest in Africa. Mauritius is ranked as the most competitive and one of the most developed economies in the African region.
The main pillars of the Mauritian economy are manufacturing, financial services and information and communications technology. Mauritius is a welfare state. Along with the other Mascarene Islands, Mauritius is known for its varied flora and fauna, with many species endemic to the island; the island was the only known home of the dodo, along with several other avian species, was made extinct by human activities shortly after the island's settlement. The first historical evidence of the existence of an island now known as Mauritius is on a map produced by the Italian cartographer Alberto Cantino in 1502. From this, it appears that Mauritius was first named Dina Arobi around 975 by Arab sailors, the first people to visit the island. In 1507, Portuguese sailors visited the uninhabited island; the island appears with a Portuguese name Cirne on early Portuguese maps from the name of a ship in the 1507 expedition. Another Portuguese sailor, Dom Pedro Mascarenhas, gave the name Mascarenes to the Archipelago.
In 1598, a Dutch squadron under Admiral Wybrand van Warwyck landed at Grand Port and named the island Mauritius, in honour of Prince Maurice van Nassau, stadholder of the Dutch Republic. The island became a French colony and was renamed Isle de France. On 3 December 1810, the French surrendered the island to Great Britain during the Napoleonic Wars. Under British rule, the island's name reverted to Mauritius. Mauritius is commonly known as Maurice and Île Maurice in French, Moris in Mauritian Creole; the island of Mauritius was uninhabited before its first recorded visit during the Middle Ages by Arab sailors, who named it Dina Arobi. In 1507, Portuguese sailors came to the uninhabited island and established a visiting base. Diogo Fernandes Pereira, a Portuguese navigator, was the first European known to land in Mauritius, he named the island "Ilha do Cirne". The Portuguese did not stay. In 1598 a Dutch squadron under Admiral Wybrand van Warwyck landed at Grand Port and named the island "Mauritius" after Prince Maurice of Nassau of the Dutch Republic.
The Dutch inhabited the island in 1638, from which they exploited ebony trees and introduced sugar cane, domestic animals and deer. It was from here; the first Dutch settlement lasted twenty years. Several attempts were subsequently made, but the settlements never developed enough to produce dividends, causing the Dutch to abandon Mauritius in 1710. France, which controlled neighbouring Île Bourbon, took control of Mauritius in 1715 and renamed it Isle de France. In 1723, the Code Noir was established to categorise one group of human beings as "goods", in order for the owner of these goods to be able to obtain insurance money and compensation in case of loss of his "goods"; the 1735 arrival of French governor Bertrand-François Mahé de La Bourdonnais coincided with development of a prosperous economy based on sugar production. Mahé de La Bourdonnais established Port Louis as a shipbuilding centre. Under his governorship, numerous buildings were erected, a number of which are sti
United States Fish and Wildlife Service
The United States Fish and Wildlife Service is an agency of the US Federal Government within the US Department of the Interior dedicated to the management of fish and natural habitats. The mission of the agency is "working with others to conserve and enhance fish, wildlife and their habitats for the continuing benefit of the American people." Aurelia Skipwith is Trump's nominee. Among the responsibilities of the FWS are enforcing federal wildlife laws. Sub-units of the FWS include: National Wildlife Refuge System—560 National Wildlife Refuges and thousands of small wetlands and other special management areas covering over 150 million acres Division of Migratory Bird Management Federal Duck Stamp National Fish Hatchery System—70 National Fish Hatcheries and 65 Fish and Wildlife Conservation Offices Endangered Species program—86 Ecological Services Field Stations International Affairs Program National Conservation Training Center USFWS Office of Law Enforcement Clark R. Bavin National Fish and Wildlife Forensic Laboratory Landscape Conservation CooperativesThe vast majority of fish and wildlife habitat is on non-federal state or private land.
Therefore, the FWS works with private groups such as Partners in Flight and Sport Fishing and Boating Partnership Council to promote voluntary habitat conservation and restoration. The FWS employs 9,000 people and is organized into a central administrative office in Falls Church, eight regional offices, nearly 700 field offices distributed throughout the United States; the FWS originated in 1871 as the United States Commission on Fish and Fisheries, more referred to as the United States Fish Commission, created by the United States Congress with the purpose of studying and recommending solutions to a noted decline in the stocks of food fish. Spencer Fullerton Baird was appointed its first commissioner. In 1903, the Fish Commission was reorganized as the United States Bureau of Fisheries. In 1885–1886, the Division of Economic Ornithology and Mammalogy was established within the United States Department of Agriculture. In 1896 it became the Division of Biological Survey, its early work focused on the effect of birds in controlling agricultural pests and mapping the geographical distribution of plants and animals in the United States.
Clinton Hart Merriam headed the Bureau for 25 years and became a national figure for improving the scientific understanding of birds and mammals in the United States. Jay Norwood Darling was appointed Chief of the new Bureau of Biological Survey in 1934. Under Darling's guidance, the Bureau began an ongoing legacy of protecting vital natural habitat throughout the country; the FWS was created in 1940, when the Bureaus of Fisheries and Biological Survey were combined after being moved to the Department of the Interior. In 1959, the methods used by FWS's Animal Damage Control Program were featured in the Tom Lehrer song "Poisoning Pigeons in the Park"; the FWS governs six US National Monuments: Hanford Reach National Monument in Washington state. Pursuant to the eagle feather law, Title 50, Part 22 of the Code of Federal Regulations, the Bald and Golden Eagle Protection Act, the US Fish and Wildlife Service administers the National Eagle Repository and the permit system for Native American religious use of eagle feathers.
These exceptions only apply to Native Americans that are registered with the federal government and are enrolled with a federally recognized tribe. In the late 1990s and early 2000s, the FWS began to incorporate the research of tribal scientists into conservation decisions; this came on the heels of Native American traditional ecological knowledge gaining acceptance in the scientific community as a reasonable and respectable way to gain knowledge of managing the natural world. Additionally, other natural resource agencies within the United States government, such as the USDA, have taken steps to be more inclusive of tribes, native people, tribal rights; this has marked a transition to a relationship of more co-operation rather than the tension between tribes and government agencies seen historically. Today, these agencies work with tribal governments to ensure the best conservation decisions are made and that tribes retain their sovereignty. Federal law enforcement in the United States Atlantic Coastal Cooperative Statistics Program National Fish and Wildlife Forensics Laboratory National Oceanic and Atmospheric Admini
Kerala, locally known as Keralam, is a state on the southwestern, Malabar Coast of India. It was formed on 1 November 1956, following passage of the States Reorganisation Act, by combining Malayalam-speaking regions. Spread over 38,863 km2, Kerala is the twenty-second largest Indian state by area, it is bordered by Karnataka to the north and northeast, Tamil Nadu to the east and south, the Lakshadweep Sea and Arabian Sea to the west. With 33,387,677 inhabitants as per the 2011 Census, Kerala is the thirteenth-largest Indian state by population, it is divided into 14 districts with the capital being Thiruvananthapuram. Malayalam is the most spoken language and is the official language of the state; the Chera Dynasty was the first prominent kingdom based in Kerala. The Ay kingdom in the deep south and the Ezhimala kingdom in the north formed the other kingdoms in the early years of the Common Era; the region had been a prominent spice exporter since 3000 BCE. The region's prominence in trade was noted in the works of Pliny as well as the Periplus around 100 CE.
In the 15th century, the spice trade attracted Portuguese traders to Kerala, paved the way for European colonisation of India. At the time of Indian independence movement in the early 20th century, there were two major princely states in Kerala-Travancore State and the Kingdom of Cochin, they united to form the state of Thiru-Kochi in 1949. The Malabar region, in the northern part of Kerala had been a part of the Madras province of British India, which became a part of the Madras State post-independence. After the States Reorganisation Act, 1956, the modern-day state of Kerala was formed by merging the Malabar district of Madras State, the state of Thiru-Kochi, the taluk of Kasaragod in South Canara, a part of Madras State; the economy of Kerala is the 12th-largest state economy in India with ₹7.73 lakh crore in gross domestic product and a per capita GDP of ₹163,000. Kerala has the lowest positive population growth rate in India, 3.44%. The state has witnessed significant emigration to Arab states of the Persian Gulf during the Gulf Boom of the 1970s and early 1980s, its economy depends on remittances from a large Malayali expatriate community.
Hinduism is practised by more than half of the population, followed by Christianity. The culture is a synthesis of Aryan, Dravidian and European cultures, developed over millennia, under influences from other parts of India and abroad; the production of pepper and natural rubber contributes to the total national output. In the agricultural sector, tea, coffee and spices are important; the state's coastline extends for 595 kilometres, around 1.1 million people in the state are dependent on the fishery industry which contributes 3% to the state's income. The state has the highest media exposure in India with newspapers publishing in nine languages English and Malayalam. Kerala is one of the prominent tourist destinations of India, with backwaters, hill stations, Ayurvedic tourism and tropical greenery as its major attractions; the name Kerala has an uncertain etymology. One popular theory derives Kerala from alam; the word Kerala is first recorded as Keralaputra in a 3rd-century BCE rock inscription left by the Maurya emperor Ashoka, one of his edicts pertaining to welfare.
The inscription refers to the local ruler as Keralaputra. This contradicts the theory that Kera is from "coconut tree". At that time, one of three states in the region was called Cheralam in Classical Tamil: Chera and Kera are variants of the same word; the word Cheral refers to the oldest known dynasty of Kerala kings and is derived from the Proto-Tamil-Malayalam word for "lake". The earliest Sanskrit text to mention Kerala is the Aitareya Aranyaka of the Rigveda. Kerala is mentioned in the Ramayana and the Mahabharata, the two Hindu epics; the Skanda Purana mentions the ecclesiastical office of the Thachudaya Kaimal, referred to as Manikkam Keralar, synonymous with the deity of the Koodalmanikyam temple. Keralam may stem from the Classical Tamil chera alam; the Greco-Roman trade map. According to Tamil classic Purananuru, Chera king Senkuttuvan conquered the lands between Kanyakumari and the Himalayas. Lacking worthy enemies, he besieged the sea by throwing his spear into it. According to the 17th century Malayalam work Keralolpathi, the lands of Kerala were recovered from the sea by the axe-wielding warrior sage Parasurama, the sixth avatar of Vishnu.
Parasurama threw his axe across the sea, the water receded as far as it reached. According to legend, this new area of land extended from Gokarna to Kanyakumari; the land which rose from sea was filled with unsuitable for habitation. Out of respect and all snakes were appo
The snakeheads are members of the freshwater perciform fish family Channidae, native to parts of Africa and Asia. These elongated, predatory fish are distinguished by their long dorsal fins, large mouths, shiny teeth, they breathe air with gills. They have suprabranchial organs which develop when they grow older, which are primitive forms of labyrinth organs; the two extant genera are Channa in Parachanna in Africa, consisting of about 50 species. They are valuable as a food source and have become notorious as an intentionally released invasive species; the various species of snakeheads differ in size. Most other snakeheads reach between 90 cm. Five species can reach 1 m or more. Snakeheads are thrust-feeders that consume plankton, aquatic insects, mollusks when small; as adults, they feed on other fish or on frogs. In rare cases, small mammals such as rats are eaten; the Channidae are well known from numerous specimens. They originated in the south Himalayan region of the Indian subcontinent at least 50 million years ago, during the Early Eocene epoch.
Two of the earliest known species, Eochanna chorlakkiensis Roe 1991 and Anchichanna kuldanensis Murray & Thewissen, 2008, have both been found in the Middle Eocene of Pakistan. By 17 Mya, during the Early Miocene, Channidae had spread into western and central Eurasia, by 8 Mya, during the late Tortonian, they existed throughout Africa and East Asia; as Channidae are adapted to climates of high precipitation with mean temperatures of 20°C, their migrations into Europe and Asia correspond to the development of the Intertropical Convergence Zone, which increased air humidity, the intensification of the East Asian monsoon. Both weather patterns emerged due to greater vertical growth of the Alps and Himalayas, which affected Eurasian climatic patterns. Snakeheads can become invasive species and cause ecological damage because in many areas to which they are not native the absence of natural enemies gives them apex predator status. Not only can they breathe air, but they can survive on land for up to four days, provided they are wet, are known to migrate up to 400 m on wet land to other bodies of water by wriggling with their bodies and fins.
National Geographic has referred to snakeheads as "fishzilla" and the National Geographic Channel reported the "northern snakehead reaches sexual maturity by age two or three. Each spawning-age female can release up to 15,000 eggs at once. Snakeheads can mate as as five times a year; this means in just two years, a single female can release up to 150,000 eggs.""Since 2002, it has been illegal to possess a live snakehead in many US states, where they are considered a destructive invasive species." Virginia has criminalized the "introduc" of snakeheads into the state without specific authorization, although the relevant statute does not explain whether mere importation is sufficient to constitute "introduc into the Commonwealth" or whether instead release into the environment is required. Humans have been introducing snakeheads to nonindigenous waters for over 100 years. In parts of Asia and Africa, the snakehead is considered a valuable food fish, is produced in aquacultures or by ignorance. Examples of the introduction of snakeheads to nonindigenous waters include: Channa maculata was introduced to Madagascar and to Hawaii around the end of the 19th century.
It can still be found there today. Channa striata was introduced to islands east of the Wallace line by governmental programs in the latter half of the 20th century. In Fiji, the introduction failed. Channa asiatica, native to southern China, was introduced to Taiwan and to southern Japan. Channa argus, native to northern China's Amur River, was introduced to central Asia, it was introduced from the Korean Peninsula to Japan about 100 years ago due to fisheries' motivations. Its introduction to Czechoslovakia by its government in the 1960s failed. Snakeheads became a national news topic in the United States because of the appearance of C. argus known as northern snakeheads, spawning in a Crofton, pond in 2002. Northern snakeheads became permanently established in the Potomac River around 2004. In about 120 mi of river, the population has surpassed 21,000 individuals. According to the United States Environmental Protection Agency, snakeheads have been spotted in California, Florida, Maine, Massachusetts and Rhode Island.
In particular, the bullseye snakehead has become a major problem throughout South Florida, growing larger than 14 lb. According to the International Game Fish Association, Caleb Newton, a Spotsylvania County, Virginia resident, caught a world-record 17 lb 6 oz northern snakehead at the junction of Aquia Creek and the Potomac River, United States on June 1, 2013; the previous record, 2 oz smaller, had been caught in 2004, in Miki, Japan. Snakeheads are valuable food fish. Called nga yant in Burmese, it is a prized fish eaten in a variety of ways. In Vietnam, they ca qua, or ca chuoi. Larger species, such as C. striata, C. maculata, Parachanna obscura, are farmed in aqu