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146-696: The bull shark ( Carcharhinus leucas ), also known as the Zambezi shark (informally zambi ) in Africa and Lake Nicaragua shark in Nicaragua , is a species of requiem shark commonly found worldwide in warm, shallow waters along coasts and in rivers. It is known for its aggressive nature, and presence mainly in warm, shallow brackish and freshwater systems including estuaries and (usually) lower reaches of rivers . Their aggressive nature has led to ongoing shark-culling efforts near beaches to protect beachgoers, which

292-736: A confederation of seafaring peoples contributed to the New Kingdom 's collapse in 1069   BC, commencing the Third Intermediate Period . Egypt's collapse liberated the more Egyptianised Kingdom of Kush in Nubia, who manoeuvred into power in Upper Egypt and conquered Lower Egypt in 754   BC to form the Kushite Empire . The Kushites ruled for a century and oversaw a revival in pyramid building , until they were driven out of Egypt by

438-549: A principality into a major power on the trade route between Rome and India through conquering its unfortunately unknown neighbours, gaining a monopoly on Indian Ocean trade in the region. Aksum's rise had them rule over much of the regions from Lake Tana to the valley of the Nile , and they further conquered parts of the ailing Kingdom of Kush , led campaigns against the Noba and Beja peoples, and expanded into South Arabia . This led

584-597: A Berber tribe originally from Yafran (also known as Ifrane ) in northwestern Libya , as well as the city of Ifrane in Morocco . Under Roman rule, Carthage became the capital of the province then named Africa Proconsularis , following its defeat of the Carthaginians in the Third Punic War in 146 BC, which also included the coastal part of modern Libya . The Latin suffix -ica can sometimes be used to denote

730-410: A bull shark may give birth to 1 to 13 live young. They are viviparous , born live and free-swimming. The young are about 70 cm (27.6 in) at birth. The bull shark does not rear its young; the young bull sharks are born into flat, protected areas. Coastal lagoons, river mouths, and other low-salinity estuaries are common nursery habitats. The male bull shark is able to begin reproducing around

876-440: A bull shark to be in fresh or salt water, however, is its age; as the bull shark ages, its tolerance for very low or high salinity increases. The majority of the newborn or very young bull sharks were found in the freshwater area, whereas the much older bull sharks were found to be in the saltwater areas, as they had developed a much better tolerance for the salinity. Reproduction is one of the reasons why adult bull sharks travel into

1022-700: A former Italian colony, gained independence. In 1956, Tunisia and Morocco won their independence from France. Ghana followed suit the next year (March 1957), becoming the first of the sub-Saharan colonies to be granted independence. Over the next decade, waves of decolonization took place across the continent, culminating in the 1960 Year of Africa and the establishment of the Organisation of African Unity in 1963. Portugal's overseas presence in sub-Saharan Africa (most notably in Angola , Cape Verde, Mozambique , Guinea-Bissau , and São Tomé and Príncipe) lasted from

1168-457: A handful of African countries succeeded in obtaining rapid economic growth prior to 1990. Exceptions include Libya and Equatorial Guinea, both of which possess large oil reserves. Arabian Sea The Arabian Sea's surface area is about 3,862,000 km (1,491,130 sq mi). The maximum width of the sea is approximately 2,400 km (1,490 mi), and its maximum depth is 5,395 metres (17,700 ft). The biggest river flowing into

1314-550: A land (e.g., in Celtica from Celtae , as used by Julius Caesar ). The later Muslim region of Ifriqiya , following its conquest of the Byzantine (Eastern Roman) Empire's Exarchatus Africae , also preserved a form of the name. According to the Romans, Africa lies to the west of Egypt, while "Asia" was used to refer to Anatolia and lands to the east. A definite line was drawn between

1460-677: A millennium. Towards the end of the ancient period, northern Ethiopia and Eritrea bore the Kingdom of D'mt beginning in 980   BC. In modern-day Somalia and Djibouti there was the Macrobian Kingdom , with archaeological discoveries indicating the possibility of other unknown sophisticated civilisations at this time. After D'mt's fall in the 5th century BC the Ethiopian Plateau came to be ruled by numerous smaller unknown kingdoms who experienced strong south Arabian influence , until

1606-625: A monopoly on gold heading north and salt heading south, despite not controlling the gold fields themselves, located in the forest regions . It is probable that Wagadu's dominance on trade allowed for the gradual consolidation of many polities into a confederated state , whose composites stood in varying relations to the core, from fully administered to nominal tribute-paying parity. Based on large tumuli scattered across West Africa dating to this period, it has been stipulated that relative to Wagadu, there were further simultaneous and preceding kingdoms that have unfortunately been lost to time. At

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1752-570: A native Libyan tribe, an ancestor of modern Berbers ; see Terence for discussion. The name had usually been connected with the Phoenician word ʿafar meaning "dust", but a 1981 hypothesis has asserted that it stems from the Berber word ifri (plural ifran ) meaning "cave", in reference to cave dwellers. The same word may be found in the name of the Banu Ifran from Algeria and Tripolitania ,

1898-652: A pregnant shark weighing 347.8 kg (767 lb) and measuring 3 m (10 ft) long was caught in February 2019, followed by another specimen weighing about 350 kg (770 lb) and measuring about the same in length, in January 2020. Unconfirmed reports suggest that the very largest, exceptional specimens can possibly weigh up to 900 kg (2,000 lb). The bull shark is commonly found worldwide in coastal areas of warm oceans, in rivers and lakes , and occasionally salt and freshwater streams if they are deep enough. It

2044-466: A significantly reduced concentration of urea within their blood. Despite this, the solute composition (i.e. osmolarity) of a bull shark in fresh water is still much higher than that of the external environment. This results in a large influx of water across the gills due to osmosis and loss of sodium and chloride from the shark's body. However, bull sharks in fresh water possess several organs with which to maintain appropriate salt and water balance; these are

2190-464: A transition from " informal imperialism " – military influence and economic dominance – to direct rule. Imperial rule by Europeans continued until after the conclusion of World War II , when almost all remaining colonial territories gradually obtained formal independence. Independence movements in Africa gained momentum following World War II, which left the major European powers weakened. In 1951, Libya,

2336-499: Is diadromous , meaning they can swim between salt and fresh water with ease, as they are euryhaline fish—able to quickly adapt to a wide range of salinities. Thus, the bull shark is one of the few cartilaginous fishes that have been reported in freshwater systems. Many of the euryhaline fish are bony fishes, such as salmon or tilapia , and are not closely related to bull sharks. Evolutionary assumptions can be made to help explain this sort of evolutionary disconnect, with one being that

2482-407: Is a marine apex predator , capable of taking a variety of prey. The bull shark's diet consists mainly of bony fish and small sharks, including other bull sharks, and stingrays. Their diet can also include turtles, birds, dolphins, terrestrial mammals, crustaceans , and echinoderms . They hunt in murky waters where it is harder for the prey to see the shark coming. Bull sharks have been known to use

2628-635: Is a warm-water, deep-sea port situated at Gwadar in Balochistan at the apex of the Arabian Sea and at the entrance of the Persian Gulf, about 460 km west of Karachi and approximately 75 km (47 mi) east of Pakistan's border with Iran. The port is located on the eastern bay of a natural hammerhead-shaped peninsula jutting out into the Arabian Sea from the coastline. Port of Salalah in Salalah, Oman

2774-491: Is able to discriminate between colors of mesh netting that is present underwater. It was found that bull sharks tended to avoid mesh netting of bright colors rather than colors that blended in with the water. Bright yellow mesh netting was found to be easily avoided when it was placed in the path of the bull shark. This was found to be the reason that sharks are attracted to bright yellow survival gear rather than ones that were painted black. In 2008, researchers tagged and recorded

2920-492: Is also a major port in the area. The International Task Force often uses the port as a base. There is a significant number of warships of all nations coming in and out of the port, which makes it a very safe bubble. The port handled just under 3.5m teu in 2009. There are several islands in the Arabian Sea, with the most important ones being Lakshadweep Islands (India), Socotra (Yemen), Masirah (Oman) and Astola Island (Pakistan). The Lakshadweep Islands (formerly known as

3066-607: Is being conducted to come up with conservation solutions for the bull sharks. One example is The Nature Conservancy satellite tagging sharks to track their migration and find their habitats in order to guide what areas require further protection projects. Africa Africa is the world's second-largest and second-most populous continent after Asia . At about 30.3 million km (11.7 million square miles) including adjacent islands, it covers 20% of Earth 's land area and 6% of its total surface area. With nearly 1.4 billion people as of 2021, it accounts for about 18% of

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3212-568: Is found to a depth of 150 m (490 ft), but does not usually swim deeper than 30 m (98 ft). In the Atlantic , it is found from Massachusetts to southern Brazil , and from Morocco to Angola . Populations of bull sharks are also found in several major rivers, with more than 500 bull sharks thought to be living in the Brisbane River . One was reportedly seen swimming the flooded streets of Brisbane , Queensland, Australia , during

3358-571: Is listed as a vulnerable species on the IUCN Red List and the population is currently reported as decreasing. Despite their status, the species isn't named as a protected species. Threats to the bull shark are numerous, such as getting caught in fishing nets, overfishing for their oil, skin, and meat, pollution to their habitat, and more. In many areas of the world, including Australia and South Africa, there are shark-culling measures around beaches to prevent attacks on beach-goers. Researchers tried to fix

3504-787: Is not always to be taken literally. Africa is considered by most paleoanthropologists to be the oldest inhabited territory on Earth, with the Human species originating from the continent. During the mid-20th century, anthropologists discovered many fossils and evidence of human occupation perhaps as early as seven million years ago ( Before present , BP). Fossil remains of several species of early apelike humans thought to have evolved into modern humans, such as Australopithecus afarensis radiometrically dated to approximately 3.9–3.0 million years BP, Paranthropus boisei (c. 2.3–1.4 million years BP) and Homo ergaster (c. 1.9 million–600,000 years BP) have been discovered. After

3650-573: Is one of the causes of bull shark populations continuing to decrease. Bull sharks are currently listed as vulnerable on the IUCN Red List. Bull sharks are euryhaline and can thrive in both salt and fresh water. They are known to travel far up rivers, and have been known to travel up the Mississippi River as far as Alton, Illinois , about 1,100 kilometres (700 mi) from the ocean, but few freshwater interactions with humans have been recorded. Larger-sized bull sharks are probably responsible for

3796-465: Is scarce, sharks digest for a much longer period of time in order to avoid starvation. As part of their survival mechanism, bull sharks will regurgitate the food in their stomachs in order to escape from a predator. This is a distraction tactic; if the predator moves to eat the regurgitated food the bull shark can use the opportunity to escape. Bull sharks mate during late summer and early autumn, often in bays and estuaries. After gestating for 12 months,

3942-793: Is surrounded by the Mediterranean Sea to the north, the Arabian Plate and the Gulf of Aqaba to the northeast, the Indian Ocean to the southeast and the Atlantic Ocean to the west. The continent includes Madagascar and various archipelagos . It contains 54 fully recognised sovereign states , eight cities and islands that are part of non-African states , and two de facto independent states with limited or no recognition . This count does not include Malta and Sicily , which are geologically part of

4088-649: The 11th dynasty , based in Thebes , conquered the others to form the Middle Kingdom of Egypt , with the 12th dynasty expanding into Lower Nubia at the expense of Kerma . In 1700   BC, the Middle Kingdom fractured in two, ushering in the Second Intermediate Period . The Hyksos , a militaristic people from Palestine , invaded and conquered Lower Egypt, while Kerma coordinated invasions deep into Egypt to reach its greatest extent. In 1550   BC,

4234-627: The 18th dynasty expelled the Hyksos , and established the New Kingdom of Egypt . Using the advanced military technology the Hyksos had brought, the New Kingdom conquered the Levant from the Canaanites , Mittani , Amorites , and Hittites , and extinguished Kerma , incorporating Nubia into the empire, and sending the Egyptian empire into its golden age. Internal struggles, drought, famine, and invasions by

4380-517: The 2010–11 Queensland floods . Several were sighted in one of the main streets of Goodna , Queensland, shortly after the peak of the January 2011, floods. A large bull shark was caught in the canals of Scarborough , just north of Brisbane within Moreton Bay. Still greater numbers are in the canals of the Gold Coast, Queensland . In the warmer months of the year, bull sharks frequent Sydney Harbour . In

4526-579: The Age of Sail . By the time of Julius Caesar , several well-established combined land-sea trade routes depended upon water transport through the sea around the rough inland terrain features to its north. These routes usually began in the Far East or down river from Madhya Pradesh , India with transshipment via historic Bharuch (Bharakuccha), traversed past the inhospitable coast of modern-day Iran, then split around Hadhramaut , Yemen into two streams north into

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4672-659: The Benin Empire . Towards the end of the 3rd century AD, a wet period in the Sahel created areas for human habitation and exploitation that had not been habitable for the best part of a millennium, with the Kingdom of Wagadu , the local name of the Ghana Empire , rising out of the Tichitt culture , growing wealthy following the introduction of the camel to the western Sahel, revolutionising

4818-521: The Cold War , and neocolonialism . Despite this low concentration of wealth, recent economic expansion and a large and young population make Africa an important economic market in the broader global context. Africa has a large quantity of natural resources and food resources, including diamonds , sugar , salt , gold , iron , cobalt , uranium , copper , bauxite , silver , petroleum , natural gas , cocoa beans , and tropical fruit . The continent

4964-805: The Congo Basin , the Empire of Kitara in the African Great Lakes , the Luba Empire in the Upemba Depression , the Kilwa Sultanate in the Swahili coast by crowding out Azania , with Rhapta being its last stronghold by the 1st century AD, and forming various city states constituting the Swahili civilisation . These migrations also prefaced the Kingdom of Mapungubwe in the Zambezi basin . After reaching

5110-726: The Ekoi civilisation rose circa 2nd century AD, and are most notable for constructing the Ikom monoliths and developing the Nsibidi script . Pre-colonial Africa possessed as many as 10,000 different states and polities. These included small family groups of hunter-gatherers such as the San people of southern Africa; larger, more structured groups such as the family clan groupings of the Bantu peoples of central, southern, and eastern Africa; heavily structured clan groups in

5256-595: The Fatimids , Almoravids , Almohads , Ayyubids , Mamluks , Kongo , Mwene Muji , Luba , Lunda , Kitara , Aksum , Ethiopia , Adal , Ajuran , Kilwa , Sakalava , Imerina , Maravi , Mutapa , Rozvi , Mthwakazi , and Zulu . Slave trades created various diasporas , especially in the Americas . From the late 19th century to early 20th century, driven by the Second Industrial Revolution , most of Africa

5402-536: The Ganges , Bramaputra, Mahanadi, and other Indian rivers and have bitten bathers. Many of these bite incidents were attributed to the Ganges shark , Glyphis gangeticus , a critically endangered river shark species, although the sand tiger shark was also blamed during the 1960s and 1970s. Bull sharks have also attacked humans off the coast of Florida. Behavioral studies have confirmed that sharks can take visual cues to discriminate between different objects. The bull shark

5548-617: The Horn of Africa ; the large Sahelian kingdoms ; and autonomous city-states and kingdoms, such as those of the Akan ; Edo , Yoruba , and Igbo people in West Africa; and the Swahili coastal trading towns of Southeast Africa. By the 9th century AD, a string of dynastic states, including the earliest Hausa states, stretched across the sub-Saharan savannah from the western regions to central Sudan. The most powerful of these states were Ghana , Gao , and

5694-718: The Isthmus of Suez in Egypt. Other migrations of modern humans within the African continent have been dated to that time, with evidence of early human settlement found in Southern Africa, Southeast Africa, North Africa, and the Sahara . The size of the Sahara has historically been extremely variable, with its area rapidly fluctuating and at times disappearing depending on global climatic conditions. At

5840-538: The Jersey Shore shark attacks of 1916 . While it is a common misconception that these attacks were the inspiration for the novel Jaws , its author Peter Benchley has stated this is not the case. The speculation that bull sharks may have been responsible is based on two fatal bites occurring in brackish and fresh water. Bull sharks have attacked swimmers around the Sydney Harbour inlets. In India, bull sharks swim up

5986-667: The Kanem-Bornu Empire . Ghana declined in the eleventh century, but was succeeded by the Mali Empire , which consolidated much of western Sudan in the thirteenth century. Kanem accepted Islam in the eleventh century. In the forested regions of the West African coast, independent kingdoms grew with little influence from the Muslim north. The Kingdom of Nri , which was ruled by the Eze Nri ,

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6132-524: The Kingdom of Dahomey , and the Oyo Empire ) adopted different ways of adapting to the shift. Asante and Dahomey concentrated on the development of "legitimate commerce" in the form of palm oil , cocoa , timber and gold, forming the bedrock of West Africa's modern export trade. The Oyo Empire, unable to adapt, collapsed into civil wars. The Scramble for Africa was the conquest and colonisation of most of Africa by seven Western European powers driven by

6278-661: The Mauro-Roman Kingdom and its numerous successor polities in the Maghreb, namely the kingdoms of Ouarsenis , Aurès , and Altava . The Vandals ruled Ifriqiya for a century until Byzantine reconquest in the early 6th century AD. The Byzantines and the Berber kingdoms fought minor inconsequential conflicts, such as in the case of Garmul , however largely coexisted. Further inland to the Byzantine Exarchate of Africa were

6424-617: The Mississippi River as Alton, Illinois . Bull sharks have also been found in the Potomac River in Maryland . From 1996 to 2013, a golf course lake at Carbrook , Logan City , Queensland, Australia was the home to several bull sharks. They were trapped following a flood of the Logan and Albert Rivers in 1996, and resided in the 51 acres (21 ha) lake until 2013, when they disappeared after another series of floods. The golf course capitalized on

6570-607: The Noba caused their disintegration into Makuria , Alodia , and Nobatia in the 5th century   AD. The Romans managed to hold on to Egypt for the rest of the ancient period. In the Horn of Africa , there was the Land of Punt , a kingdom on the Red Sea , likely located in modern-day Eritrea or northern Somaliland . The Ancient Egyptians initially traded via middle-men with Punt until in 2350   BC when they established direct relations. They would become close trading partners for over

6716-430: The Nok culture from 1500 BC in modern-day Nigeria , the Daima culture around Lake Chad from 550   BC, Djenné-Djenno from 250   BC in modern-day Mali , and the Serer civilisation in modern-day Senegal , which built the Senegambian stone circles from the 3rd century BC. There is also detailed record of Igodomigodo , a small kingdom founded presumably in 40   BC, which would later go on to form

6862-399: The Ovambo kingdoms , most of which were later conquered. The 1884 Berlin Conference regulated European colonisation and trade in Africa, and is seen as emblematic of the "scramble". In the last quarter of the 19th century, there were considerable political rivalries between the European empires , which provided the impetus for the colonisation. The later years of the 19th century saw

7008-486: The Pacific Ocean , it can be found from Baja California to Ecuador . The bull shark has traveled 4,000 km (2,500 mi) up the Amazon River to Iquitos in Peru and north Bolivia . It also lives in freshwater Lake Nicaragua , in the Ganges and Brahmaputra Rivers of West Bengal , and Assam in Eastern India and adjoining Bangladesh . It can live in water with a high salt content as in St. Lucia Estuary in South Africa . Bull sharks have been recorded in

7154-402: The Periplus of the Erythraean Sea , as well as in some ancient maps, Erythraean Sea refers to the whole area of the northwestern Indian Ocean, including the Arabian Sea. The Arabian Sea has been an important marine trade route since the era of the coastal sailing vessels from possibly as early as the 3rd millennium BCE, certainly the late 2nd millennium BCE through the later days known as

7300-404: The Punic Wars against the expansionary Roman Republic , however momentum in these wars was not linear, with Carthage initially experiencing considerable success in the Second Punic War following Hannibal 's infamous crossing of the alps into northern Italy . Their defeat and subsequent collapse of their empire would produce two further polities in the Maghreb; Numidia , which had assisted

7446-447: The Romans in 30   BC. The Crisis of the Third Century in the Roman Empire freed the Levantine city state of Palmyra , which conquered Egypt ; their brief rule ended when they were reconquered by the Romans . In the midst of this, Kush regained independence from Egypt, and they would persist as a major regional power until, having been weakened from internal rebellion amid worsening climatic conditions, invasions by Aksum and

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7592-494: The Sanhaja in modern-day Algeria , a broad grouping of three groupings of tribal confederations , one of which is the Masmuda grouping in modern-day Morocco , along with the nomadic Zenata ; their composite tribes would later go onto shape much of North African history . In the western Sahel the rise of settled communities occurred largely as a result of the domestication of millet and of sorghum . Archaeology points to sizable urban populations in West Africa beginning in

7738-488: The Sao civilisation flourished for over a millennium beginning in the 6th century BC, in territory that later became part of present-day Cameroon and Chad . Sao artifacts show that they were skilled workers in bronze , copper , and iron , with finds including bronze sculptures, terracotta statues of human and animal figures, coins, funerary urns, household utensils, jewellery, highly decorated pottery, and spears. Nearby, around Lake Ejagham in south-west Cameroon ,

7884-419: The Sassanid Empire and the Himyarite Kingdom in Arabia. The Maghreb and Ifriqiya were mostly cut off from the cradle of civilisation in Egypt by the Libyan desert , exacerbated by Egyptian boats being tailored to the Nile and not coping well in the open Mediterranean Sea . This caused its societies to develop contiguous to those of Southern Europe , until Phoenician settlements came to dominate

8030-417: The Second Industrial Revolution during the era of " New Imperialism " (1833–1914): Belgium , France , Germany , United Kingdom , Italy , Portugal and Spain . In 1870, 10% of the continent was formally under European control. By 1914, this figure had risen to almost 90%; the only states retaining sovereignty were Liberia , Ethiopia , Egba , Aussa , Senusiyya , Mbunda , the Dervish State , and

8176-446: The Tigris River since at least 1924 as far upriver as Baghdad, and has been rumored to also inhabit the Cahora Bassa lake upstream of the Zambezi . The species has a distinct preference for warm currents. After Hurricane Katrina , many bull sharks were sighted in Lake Pontchartrain . In July 2023 some local fishermen in the Atchafalaya River have reported increasing numbers. Bull sharks have occasionally gone as far upstream in

8322-404: The Zambezi , the Bantu continued southward, with eastern groups continuing to modern-day Mozambique and reaching Maputo in the 2nd century AD. Further to the south, settlements of Bantu peoples who were iron-using agriculturists and herdsmen were well established south of the Limpopo River by the 4th century AD, displacing and absorbing the Khoisan . By the Chari River south of Lake Chad

8468-475: The bump-and-bite technique to attack their prey. After the first initial contact, they continue to bite and tackle prey until the prey is unable to flee. The bull shark is a solitary hunter, though may briefly pair with another bull shark to make hunting and tricking prey easier. Sharks are opportunistic feeders, and the bull shark is no exception to this, as it is part of the Carcharhinus family of sharks. Normally, sharks eat in short bursts, and when food

8614-419: The presidential system of rule. However, few of them have been able to sustain democratic governments on a permanent basis—per the criteria laid out by Lührmann et al. (2018), only Botswana and Mauritius have been consistently democratic for the entirety of their post-colonial history. Most African countries have experienced several coups or periods of military dictatorship . Between 1990 and 2018, though,

8760-780: The trans-Saharan trade that linked their capital and Aoudaghost with Tahert and Sijilmasa in North Africa. Soninke traditions likely contain content from prehistory, mentioning four previous foundings of Wagadu , and holds that the final founding of Wagadu occurred after their first king did a deal with Bida , a serpent deity who was guarding a well, to sacrifice one maiden a year in exchange for assurance regarding plenty of rainfall and gold supply. Wagadu's core traversed modern-day southern Mauritania and western Mali , and Soninke tradition portrays early Ghana as warlike, with horse-mounted warriors key to increasing its territory and population, although details of their expansion are extremely scarce. Wagadu made its profits from maintaining

8906-410: The tropic of Cancer , in the northern temperate zone . In the other extreme of the continent, southern Namibia , southern Botswana , great parts of South Africa , the entire territories of Lesotho and Eswatini and the southern tips of Mozambique and Madagascar are located below the tropic of Capricorn , in the southern temperate zone . Africa is highly biodiverse ; it is the continent with

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9052-424: The written word . During the colonial period , oral sources were deprecated by European historians, which gave them the impression Africa had no recorded history. African historiography became organized at the academic level in the mid-20th century, and saw a movement towards utilising oral sources in a multidisciplinary approach, culminating in the General History of Africa , edited by specialists from across

9198-459: The 16th and 19th centuries. In West Africa, the decline of the Atlantic slave trade in the 1820s caused dramatic economic shifts in local polities. The gradual decline of slave-trading, prompted by a lack of demand for slaves in the New World , increasing anti-slavery legislation in Europe and America, and the British Royal Navy's increasing presence off the West African coast, obliged African states to adopt new economies. Between 1808 and 1860,

9344-420: The 16th century to 1975, after the Estado Novo regime was overthrown in a military coup in Lisbon . Rhodesia unilaterally declared independence from the United Kingdom in 1965, under the white minority government of Ian Smith , but was not internationally recognized as an independent state (as Zimbabwe ) until 1980, when black nationalists gained power after a bitter guerrilla war . Although South Africa

9490-423: The 1st and 4th cataracts of the Nile . The 4th dynasty oversaw the height of the Old Kingdom , and constructed many great pyramids . Under the 6th dynasty power gradually decentralised to the nomarchs, culminating in the disintegration of the kingdom, exacerbated by drought and famine, thus commencing the First Intermediate Period in 2200   BC. This shattered state would last until 2055   BC when

9636-406: The 2nd century BC Mauretania fought alongside Numidia's Jugurtha in the Jugurthine War against the Romans after he had usurped the Numidian throne from a Roman ally. Together they inflicted heavy casualties that quaked the Roman Senate , with the war only ending inconclusively when Mauretania's Bocchus I sold out Jugurtha to the Romans. At the turn of the millennium, they both would face

9782-415: The 3rd or 2nd millennium BCE. Major seaports include Kandla Port , Mundra Port , Pipavav Port , Dahej Port , Hazira Port , Mumbai Port , Nhava Sheva Port (Navi Mumbai) , Mormugão Port (Goa) , New Mangalore Port and Kochi Port in India, the Port of Karachi , Port Qasim , and the Gwadar Port in Pakistan, Chabahar Port in Iran and the Port of Salalah in Salalah , Oman . The largest islands in

9928-418: The 4th millennium BC the Congo Basin was inhabited by the Bambenga , Bayaka , Bakoya , and Babongo in the west, the Bambuti in the east , and the Batwa who were widely scattered and also present in the Great Lakes region ; together they are grouped as Pygmies . On the later-named Swahili coast there were Cushitic -speaking peoples, and the Khoisan (a neologism for the Khoekhoe and San ) in

10074-416: The 4th millennium BC, which had crucially developed iron metallurgy by 1200   BC, in both smelting and forging for tools and weapons. Extensive east-west belts of deserts , grasslands , and forests from north to south were crucial for the moulding of their respective societies and meant that prior to the accession of trans-Saharan trade routes , symbiotic trade relations developed in response to

10220-405: The African continent. Algeria is Africa's largest country by area, and Nigeria is its largest by population. African nations cooperate through the establishment of the African Union , which is headquartered in Addis Ababa . Africa straddles the equator and the prime meridian . It is the only continent to stretch from the northern temperate to the southern temperate zones. The majority of

10366-440: The Arabian Sea include Socotra ( Yemen ), Masirah Island (Oman), Lakshadweep (India) and Astola Island (Pakistan). The countries with coastlines on the Arabian Sea are Yemen, Oman, Pakistan, Iran, India and the Maldives . The International Hydrographic Organization defines the limits of the Arabian Sea as follows: The International Indian Ocean Expedition in 1959 was among the first to perform hydrographic surveys of

10512-513: The Arabian Sea is warming monotonously; it possibly is due to global warming. The intensification and northward shift of the summer monsoon low-level jet over the Arabian Sea from 1979 to 2015, led to increased upper ocean heat content due to enhanced downwelling and reduced southward heat transport. Regional endonyms for the Arabian sea in languages of the coastal regions surrounding it. [REDACTED]   This article incorporates text from

10658-569: The Arabian Sea. Significant bathymetric surveys were also conducted by the Soviet Union during the 1960s. Significant features in the northern Arabian Sea include the Indus Fan , the second largest fan system in the world. The De Covilhao Trough, named after the 15th century Portuguese explorer Pero de Covilhăo , reaches depths of 4,400 metres (14,436 ft) and separates the Indus Fan region from

10804-678: The Assyrians in 663   BC in reprisal for their expansion towards the Assyrian Empire . The Assyrians installed a puppet dynasty that later gained independence and once more unified Egypt , until they were conquered by the Achaemenid Empire in 525   BC. Egypt regained independence under the 28th dynasty in 404   BC but they were reconquered by the Achaemenids in 343   BC. The conquest of Achaemenid Egypt by Alexander

10950-553: The British West Africa Squadron seized approximately 1,600 slave ships and freed 150,000 Africans who were aboard. Action was also taken against African leaders who refused to agree to British treaties to outlaw the trade, for example against "the usurping King of Lagos ", deposed in 1851. Anti-slavery treaties were signed with over 50 African rulers. The largest powers of West Africa (the Asante Confederacy ,

11096-635: The Great in 332   BC marked the beginning of Hellenistic rule and the installation of the Macedonian Ptolemaic dynasty in Egypt. The Ptolemaics lost their holdings outside of Africa to the Seleucids in the Syrian Wars , expanded into Cyrenaica and subjugated Kush in the 3rd century BC. In the 1st century BC, Ptolemaic Egypt became entangled in a Roman civil war , leading to its conquest by

11242-548: The Gulf of Aden and thence into the Levant , or south into Alexandria via Red Sea ports such as Axum . Each major route involved transhipping to pack animal caravan , travel through desert country and risk of bandits and extortionate tolls by local potentates. This southern coastal route past the rough country in the southern Arabian Peninsula was significant, and the Egyptian Pharaohs built several shallow canals to service

11388-474: The Gulf of Aden. The trough, reaching depths over 5,360 metres (17,585 ft), traverses the Gulf of Aden and the Arabian Sea. The deepest known point is in the Arabian Sea limits at a depth of 5,395 metres (17,700 ft). Other significant deep points are part of the Arabian Basin, which include a 5,358 metres (17,579 ft) deep point off the northern limit of Calrsberg Ridge. Prominent sea mounts off

11534-564: The Iberian peninsula during the eleventh century. The Banu Hilal and Banu Ma'qil were a collection of Arab Bedouin tribes from the Arabian Peninsula who migrated westwards via Egypt between the eleventh and thirteenth centuries. Their migration resulted in the fusion of the Arabs and Berbers, where the locals were Arabized , and Arab culture absorbed elements of the local culture, under

11680-569: The Indian subcontinent, which increase winds blowing towards India, bringing up nutrients and reducing oxygen in the Arabian Sea's waters. In winter, phytoplankton suited to low-oxygen conditions turn the OMZ bright green. The wildlife of the Arabian sea is diverse, and entirely unique because of the geographic distribution. Recent studies by the Indian Institute of Tropical Meteorology confirmed that

11826-785: The Indian west coast include Raman Seamount named after C. V. Raman , Panikkar Seamount, named after N. K. Panikkar , and the Wadia Guyot , named after D. N. Wadia . Sind'Bad Seamount, named after the fictional explorer Sinbad the Sailor , Zheng He Seamount, and the Mount Error Guyot are some notable sea mounts in western Arabian Sea. Border and basin countries: The Arabian Sea historically and geographically has been referred to with different names by Arabian and European geographers and travelers, including Erythraean Sea , Indian Sea, Oman sea , Erythraean, Persian Sea in para No 34-35 of

11972-602: The Laccadive, Minicoy, and Aminidivi Islands) is a group of islands in the Laccadive Sea region of Arabian Sea, 200 to 440 km (120 to 270 mi) off the southwestern coast of India. The archipelago is a union territory and is governed by the Union Government of India . The islands form the smallest union territory of India with their total surface area being just 32 km (12 sq mi). Next to these islands are

12118-689: The Maldives islands. These islands are all part of the Lakshadweep-Maldives-Chagos group of islands. Zalzala Koh was an island which was around for only a few years. After the 2013 earthquake in Pakistan, the mud island was formed. By 2016 the island had completely submerged. Astola Island, also known as Jezira Haft Talar in Balochi , or 'Island of the Seven Hills', is a small, uninhabited island in

12264-635: The Oman Abyssal Plain, which eventually leads to the Gulf of Oman . The southern limits are dominated by the Arabian Basin , a deep basin reaching depths over 4,200 metres (13,780 ft). The northern sections of the Carlsberg Ridge flank the southern edge of the Arabian Basin. The deepest parts of the Arabian Sea are in the Alula-Fartak Trough on the western edge of the Arabian Sea off

12410-550: The Persian prophet Mani to consider Aksum as one of the four great powers of the 3rd century AD alongside Persia , Rome , and China . In the 4th century AD Aksum's king converted to Christianity and Aksum's population, who had followed syncretic mixes of local beliefs , slowly followed. The end of the 5th century saw Aksum allied with the Byzantine Empire , who viewed themselves as defenders of Christendom , balanced against

12556-558: The Romans in the Second Punic War, Mauretania , a Mauri tribal kingdom and home of the legendary King Atlas , and various tribes such as Garamantes , Musulamii , and Bavares . The Third Punic War would result in Carthage's total defeat in 146 BC and the Romans established the province of Africa , with Numidia assuming control of many of Carthage's African ports. Towards the end of

12702-804: The Sahara region was becoming increasingly dry and hostile. Around 3500   BC, due to a tilt in the Earth's orbit , the Sahara experienced a period of rapid desertification. The population trekked out of the Sahara region towards the Nile Valley below the Second Cataract where they made permanent or semi-permanent settlements. A major climatic recession occurred, lessening the heavy and persistent rains in Central and Eastern Africa . Since this time, dry conditions have prevailed in Eastern Africa and, increasingly during

12848-517: The Saharan climate started to become drier at an exceedingly fast pace. This climate change caused lakes and rivers to shrink significantly and caused increasing desertification . This, in turn, decreased the amount of land conducive to settlements and encouraged migrations of farming communities to the more tropical climate of West Africa. During the first millennium BC, a reduction in wild grain populations related to changing climate conditions facilitated

12994-841: The Voyage. In Indian folklore, it is referred to as Darya, Sindhu Sagar, Arab Samudra. Arab geographers, sailors and nomads used to call this sea by different names, including the Akhdar (Green) Sea, Bahre Fars (Persian Sea), the Ocean Sea, the Hindu sea, the Makran Sea, the sea of Oman; among them Zakariya al-Qazwini , Al-Masudi , Ibn Hawqal and Hafiz-i Abru . They wrote: "The green sea and Indian sea and Persian sea are all one sea and in this sea there are strange creatures." in Iran and Turkey people call it Oman sea. In

13140-643: The active reabsorption of solutes into the blood. The gills of bull sharks are likely to be involved in the uptake of sodium and chloride from the surrounding fresh water, whereas urea is produced in the liver as required with changes in environmental salinity. Recent work also shows that the differences in density of fresh water to that of marine waters result in significantly greater negative buoyancies in sharks occupying fresh water, resulting in increasing costs of living in fresh water. Bull sharks caught in freshwater have subsequently been shown to have lower liver densities than sharks living in marine waters. This may reduce

13286-524: The added cost of greater negative buoyancy. Bull sharks are able to regulate themselves to live in either fresh or salt water. It can live in fresh water for its entire life, but this does not happen, mostly due to the reproductive needs of the shark. Young bull sharks leave the brackish water in which they are born and move out into the sea to breed. While is theoretically possible for bull sharks to live purely in fresh water, experiments conducted on bull sharks found that they died within four years. The stomach

13432-460: The age of 15 years while the female cannot begin reproducing until the age of 18 years. The size of a fully matured female bull shark to produce viable eggs for fertilization seems to be 175 cm to 235 cm. The courting routine between bull sharks has not been observed in detail as of yet. The male likely bites the female on the tail until she can turn upside down and the male can copulate at that point. Mature females commonly have scratches from

13578-483: The biggest threat to bull sharks. Larger sharks, such as the tiger shark and great white shark , may attack them, but typically only target juveniles. Crocodiles may be a threat to bull sharks in rivers. Saltwater crocodiles have been observed preying on bull sharks in the rivers and estuaries of Northern Australia , and a Nile crocodile was reportedly sighted consuming a bull shark in South Africa. The bull shark

13724-543: The bull shark experienced a population bottleneck during the last ice age . This bottleneck may have separated the bull shark from the rest of the Elasmobranchii subclass and favored the genes for an osmoregulatory system. Elasmobranchs' ability to enter fresh water is limited because their blood is normally at least as salty (in terms of osmotic strength ) as seawater through the accumulation of urea and trimethylamine oxide , but bull sharks living in fresh water show

13870-539: The bull shark may be confused with the Sundarbans or Ganges shark . In Africa, it is also commonly called the Zambezi River shark, or just "zambi". Its wide range and diverse habitats result in many other local names, including Ganges River shark, Fitzroy Creek whaler, van Rooyen's shark, Lake Nicaragua shark, river shark, freshwater whaler, estuary whaler, Swan River whaler, cub shark, and shovelnose shark. Some of

14016-646: The bull shark's closest living relatives do not have the capabilities of osmoregulation . Its genus, Carcharhinus , also includes the sandbar shark , which is not capable of osmoregulation. The bull shark shares numerous similarities with river sharks of the genus Glyphis , and other species in the genus Carcharhinus , but its phylogeny has not been cleared yet. Bull sharks are large and stout, with females being larger than males. The bull shark can be up to 81 cm (2 ft 8 in) in length at birth. Adult female bull sharks average 2.4 m (8 ft) long and typically weigh 130 kg (290 lb), whereas

14162-410: The coast of Arabian Sea. Some of the major cities are Mumbai , Muscat , Karachi , Aden , Salalah , Thiruvananthapuram , Kochi , Kozhikode , Alappuzha , Kollam , Mangalore , Bhavnagar , Jamnagar , Mogadishu , Gwadar , Abu Dhabi , Mundra , Dubai , Kannur , Panaji , Karwar , Udupi , Ratnagiri , Murdeshwar , Veraval , Colombo , Takamaka , and Dhiffushi . The Arabian Sea has one of

14308-532: The continent and its countries are in the Northern Hemisphere , with a substantial portion and a number of countries in the Southern Hemisphere . Most of the continent lies in the tropics, except for a large part of Western Sahara , Algeria , Libya and Egypt , the northern tip of Mauritania , and the entire territories of Morocco , Ceuta , Melilla , and Tunisia , which in turn are located above

14454-463: The continent as a whole has trended towards more democratic governance. Upon independence an overwhelming majority of Africans lived in extreme poverty . The continent suffered from the lack of infrastructural or industrial development under colonial rule, along with political instability. With limited financial resources or access to global markets, relatively stable countries such as Kenya still experienced only very slow economic development. Only

14600-424: The continent most vulnerable to climate change . The history of Africa is long, complex, and varied, and has often been under-appreciated by the global historical community . In African societies the oral word is revered, and they have generally recorded their history via oral tradition , which has led anthropologists to term them oral civilisations, contrasted with literate civilisations which pride

14746-457: The continent's south. The Bantu expansion constituted a major series of migrations of Bantu peoples from central Africa to eastern and southern Africa and was substantial in the settling of the continent. Commencing in the 2nd millennium BC, the Bantu began to migrate from Cameroon to central, eastern, and southern Africa, laying the foundations for future states such as the Kingdom of Kongo in

14892-473: The continent. Africa, particularly Eastern Africa , is widely accepted to be the place of origin of humans and the Hominidae clade , also known as the great apes . The earliest hominids and their ancestors have been dated to around 7 million years ago, and Homo sapiens (modern human) are believed to have originated in Africa 350,000 to 260,000 years ago. Africa is also considered by anthropologists to be

15038-428: The earliest instances of agriculture in human history. Its cultivation would gradually spread across Africa, before spreading to India around 2000   BC. People around modern-day Mauritania started making pottery and built stone settlements (e.g., Tichitt , Oualata ). Fishing, using bone-tipped harpoons , became a major activity in the numerous streams and lakes formed from the increased rains. In West Africa,

15184-535: The end of the Ice ages , estimated to have been around 10,500   BC, the Sahara had again become a green fertile valley, and its African populations returned from the interior and coastal highlands in sub-Saharan Africa , with rock art paintings depicting a fertile Sahara and large populations discovered in Tassili n'Ajjer dating back perhaps 10 millennia. However, the warming and drying climate meant that by 5,000   BC,

15330-576: The evolution of Homo sapiens approximately 350,000 to 260,000 years BP in Africa, the continent was mainly populated by groups of hunter-gatherers . These first modern humans left Africa and populated the rest of the globe during the Out of Africa II migration dated to approximately 50,000 years BP, exiting the continent either across Bab-el-Mandeb over the Red Sea , the Strait of Gibraltar in Morocco, or

15476-647: The expansion of farming communities and the rapid adoption of rice cultivation around the Niger River. By the first millennium BC, ironworking had been introduced in Northern Africa. Around that time it also became established in parts of sub-Saharan Africa, either through independent invention there or diffusion from the north and vanished under unknown circumstances around 500   AD, having lasted approximately 2,000 years, and by 500   BC, metalworking began to become commonplace in West Africa. Ironworking

15622-502: The growth and expansion of Aksum in the 1st century BC. Along the Horn's coast there were many ancient Somali city-states that thrived off of the wider Red Sea trade and transported their cargo via beden , exporting myrrh , frankincense , spices , gum , incense , and ivory , with freedom from Roman interference causing Indians to give the cities a lucrative monopoly on cinnamon from ancient India . The Kingdom of Aksum grew from

15768-580: The highest among all investigated cartilaginous fishes. In early June 2012, off the coast of the Florida Keys near the western part of the Atlantic Ocean , a female believed to measure at least 2.4 m (8 ft) and 360–390 kg (800–850 lb) was caught by members of the R.J. Dunlap Marine Conservation Program. In the Arabian Sea , off the coast of Fujairah in the United Arab Emirates ,

15914-443: The historical process is largely a communal one, with eyewitness accounts, hearsay , reminiscences, and occasionally visions , dreams, and hallucinations, crafted into oral traditions . Time is sometimes mythical and social, and truth generally viewed as relativist . Oral tradition can be exoteric or esoteric . It speaks to people according to their understanding, unveiling itself in accordance with their aptitudes, and

16060-562: The kingdoms of Lower Egypt and Upper Egypt in northeast Africa . Around 3100   BC Upper Egypt conquered Lower Egypt to unify Egypt under the 1st dynasty , with the process of consolidation and assimilation completed by the time of the 3rd dynasty who formed the Old Kingdom of Egypt in 2686   BC. The Kingdom of Kerma emerged around this time to become the dominant force in Nubia , controlling territory as large as Egypt between

16206-546: The lake have later been caught in the open ocean (and vice versa), with some taking as few as seven to 11 days to complete the journey. A study of six bull sharks confined to a stagnant golf course lake in Brisbane, Australia , from 1996 to 2013 uncovered their adaptability to low-salinity environments, marking the longest recorded residency for the species under such conditions, and demonstrating their ability to live indefinitely in low-salinity aquatic environments. The bull shark

16352-514: The largest container port in India. Major Indian ports in the Arabian Sea are Mundra Port , Kandla Port , Nava Sheva , Kochi Port , Mumbai Port , Vizhinjam International Seaport Thiruvananthapuram and Mormugão . The Port of Karachi , Pakistan's largest and busiest seaport lies on the coast of the sea. It is located between the Karachi towns of Kiamari and Saddar . The Gwadar Port of Pakistan

16498-507: The largest number of megafauna species, as it was least affected by the extinction of the Pleistocene megafauna . However, Africa also is heavily affected by a wide range of environmental issues , including desertification, deforestation, water scarcity , and pollution . These entrenched environmental concerns are expected to worsen as climate change impacts Africa . The UN Intergovernmental Panel on Climate Change has identified Africa as

16644-438: The largest of the requiem sharks . Bull sharks are wider and heavier than other requiem sharks of comparable length, and are grey on top and white below. The second dorsal fin is smaller than the first. The bull shark's caudal fin is longer and lower than that of the larger sharks, and it has a small snout , and lacks an interdorsal ridge. Bull sharks have a bite force up to 5,914 newtons (1,330 lbf), weight for weight

16790-599: The last 200 years, in Ethiopia . The domestication of cattle in Africa preceded agriculture and seems to have existed alongside hunter-gatherer cultures. It is speculated that by 6,000   BC, cattle were domesticated in North Africa. In the Sahara-Nile complex, people domesticated many animals, including the donkey and a small screw-horned goat that was common from Algeria to Nubia . Between 10,000 and 9,000   BC, pottery

16936-480: The majority of nearshore shark attacks , including many incidents of shark bites attributed to other species. Unlike the river sharks of the genus Glyphis , bull sharks are not true freshwater sharks , despite their ability to survive in freshwater habitats. This shark appears in the image of the 2000 colones bill from Costa Rica . The name "bull shark" comes from the shark's stocky shape, broad, flat snout, and aggressive, unpredictable behavior. In India,

17082-437: The mating process. Since bull sharks often dwell in very shallow waters, are found in many types of habitats, are territorial by nature, and have no tolerance for provocation, they may be more dangerous to humans than any other species of shark. Bull sharks are one of the three shark species (along with the tiger shark and great white shark ) most likely to bite humans. One or several bull sharks may have been responsible for

17228-643: The most genetically diverse continent as a result of being the longest inhabited. In the 4th and 3rd millennia BC Ancient Egypt , Kerma , Punt , and the Tichitt Tradition emerged in North , East and West Africa , while from 4000 BC until 1000 AD the Bantu expansion was substantial in laying the foundations for societies and states in Central , East , and Southern Africa . Some African empires include Wagadu , Mali , Songhai , Sokoto , Ife , Benin , Asante ,

17374-399: The most lucrative trading locations in the Gulf of Tunis . Phoenician settlements subsequently grew into Ancient Carthage after gaining independence from Phoenicia in the 6th century BC, and they would build an extensive empire and a strict mercantile network, all secured by one of the largest and most powerful navies in the ancient Mediterranean . Carthage would meet its demise in

17520-479: The movements of young bull sharks in the Caloosahatchee River estuary. They were testing to find out what determined the movement of the young bull sharks. It was found that the young bull sharks synchronously moved downriver when the environmental conditions changed. This large movement of young bull sharks were found to be moving as a response rather than other external factors such as predators. The movement

17666-507: The northern tip of the Arabian Sea in Pakistan's territorial waters. Socotra, also spelled Soqotra , is the largest island, being part of a small archipelago of four islands. It lies some 240 km (150 mi) east of the Horn of Africa and 380 km (240 mi) south of the Arabian Peninsula. Masirah and the five Khuriya Muriya Islands are islands off the southeastern coast of Oman. There are many major cities and towns in

17812-567: The novelty, changing their logo to feature the sharks and hosting a monthly tournament called the "Shark Lake Challenge". The bull shark is the best known of 43 species of elasmobranch , across 10 genera and four families, to have been reported in fresh and/or brackish water. Other species that enter rivers include the stingrays ( Dasyatidae , Potamotrygonidae and others) and sawfish ( Pristidae ). Some skates ( Rajidae ), smooth dogfishes ( Triakidae ), and sandbar sharks ( Carcharhinus plumbeus ) regularly enter estuaries. The bull shark

17958-439: The official religion, built mosques, and brought to Gao Muslim scholars, including al-Maghili (d.1504), the founder of an important tradition of Sudanic African Muslim scholarship. By the eleventh century, some Hausa states – such as Kano , Jigawa , Katsina , and Gobir – had developed into walled towns engaging in trade, servicing caravans , and the manufacture of goods. Until the fifteenth century, these small states were on

18104-460: The opportunities afforded by north–south diversity in ecosystems. Various civilisations prospered in this period. From 4000   BC, the Tichitt culture in modern-day Mauritania and Mali was the oldest known complexly organised society in West Africa, with a four tiered hierarchical social structure. Other civilisations include the Kintampo culture from 2500   BC in modern-day Ghana ,

18250-524: The periphery of the major Sudanic empires of the era, paying tribute to Songhai to the west and Kanem-Borno to the east. Slavery had long been practiced in Africa. Between the 15th and the 19th centuries, the Atlantic slave trade took an estimated 7–12 million slaves to the New World. In addition, more than 1 million Europeans were captured by Barbary pirates and sold as slaves in North Africa between

18396-585: The predecessor to the African Union. The nascent countries decided to keep their colonial borders, with traditional power structures used in governance to varying degrees. Afri was a Latin name used to refer to the inhabitants of what was then known as northern Africa , located west of the Nile river, and in its widest sense referring to all lands south of the Mediterranean , also known as Ancient Libya . This name seems to have originally referred to

18542-468: The problem of sharks getting too close to land by testing out a device called the SharkSafe Barrier™. This barrier used magnetic and visual stimuli, which utilized rows of piping to create a continuous magnetic field to deter the sharks. However, researchers concluded that the technology needs to be improved upon and tested further before it can be implemented as a reliable safety measure. Other research

18688-406: The rectal gland, kidneys, liver, and gills. All elasmobranchs have a rectal gland which functions in the excretion of excess salts accumulated as a consequence of living in seawater. Bull sharks in freshwater environments decrease the salt-excretory activity of the rectal gland, thereby conserving sodium and chloride. The kidneys produce large amounts of dilute urine, but also play an important role in

18834-651: The river—it is thought to be a physiological strategy to improve juvenile survival and a way to increase overall fitness of bull sharks. The young are not born with a high tolerance for high salinity, so they are born in fresh water and stay there until they are able to travel out. Initially, scientists thought the sharks in Lake Nicaragua belonged to an endemic species, the Lake Nicaragua shark ( Carcharhinus nicaraguensis ). In 1961, following specimen comparisons, taxonomists synonymized them. Bull sharks tagged inside

18980-475: The same fate as Carthage and be conquered by the Romans who established Mauretania and Numidia as provinces of their empire, while Musulamii , led by Tacfarinas , and Garamantes were eventually defeated in war in the 1st century AD however weren't conquered. In the 5th century AD the Vandals conquered north Africa precipitating the fall of Rome . Swathes of indigenous peoples would regain self-governance in

19126-558: The sea is the Indus River . The Arabian Sea has two important branches: the Gulf of Aden in the southwest, connecting with the Red Sea through the strait of Bab-el-Mandeb ; and the Gulf of Oman to the northwest, connecting with the Persian Gulf. There are also the gulfs of Khambhat and Kutch on the Indian Coast . The Arabian Sea has been crossed by many important marine trade routes since

19272-410: The slightly smaller adult male averages 2.25 m (7 ft) and 95 kg (209 lb). While a maximum size of 3.5 m (11 ft) is commonly reported, a single record exists of a female specimen of exactly 4.0 m (13 ft). A 3.25 m (10.7 ft) long pregnant individual reached 450 kg (990 lb). The maximum weight can be over 600 kg (1,300 lb), ranking it among

19418-402: The trade, one more or less along the route of today's Suez Canal , and another from the Red Sea to the Nile River , both shallow works that were swallowed up by huge sand storms in antiquity. Later the kingdom of Axum arose in Ethiopia to rule a mercantile empire rooted in the trade with Europe via Alexandria. Jawaharlal Nehru Port in Mumbai is the largest port in the Arabian Sea, and

19564-425: The two continents by the geographer Ptolemy (85–165 CE), indicating Alexandria along the Prime Meridian and making the isthmus of Suez and the Red Sea the boundary between Asia and Africa. As Europeans came to understand the real extent of the continent, the idea of "Africa" expanded with their knowledge. Other etymological hypotheses have been postulated for the ancient name "Africa": In African societies,

19710-433: The unifying framework of Islam. Following the breakup of Mali, a local leader named Sonni Ali (1464–1492) founded the Songhai Empire in the region of middle Niger and the western Sudan and took control of the trans-Saharan trade. Sonni Ali seized Timbuktu in 1468 and Jenne in 1473, building his regime on trade revenues and the cooperation of Muslim merchants. His successor Askia Mohammad I (1493–1528) made Islam

19856-462: The wet phase ushered in an expanding rainforest and wooded savanna from Senegal to Cameroon . Between 9,000 and 5,000   BC, Niger–Congo speakers domesticated the oil palm and raffia palm . Black-eyed peas and voandzeia (African groundnuts), were domesticated, followed by okra and kola nuts . Since most of the plants grew in the forest, the Niger–Congo speakers invented polished stone axes for clearing forest. Around 4,000   BC,

20002-497: The world's human population . Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will reach 3.8 billion people by 2099. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania . Scholars have attributed this to different factors including geography , climate , corruption , colonialism ,

20148-448: The world's three largest oceanic oxygen minimum zones (OMZ), or “dead zones,” along with the eastern tropical North Pacific and the eastern tropical South Pacific. OMZs have very low levels of oxygen , sometimes so low as to be undetectable by standard equipment. The Arabian Sea's OMZ has the lowest levels of oxygen in the world, especially in the Gulf of Oman. Causes of the OMZ may include untreated sewage as well as high temperatures on

20294-418: Was rapidly conquered and colonised by European nations , save for Ethiopia and Liberia . European rule had significant impacts on Africa's societies , and colonies were maintained for the purpose of economic exploitation and extraction of natural resources. Most present states emerged from a process of decolonisation following World War II , and established the Organisation of African Unity in 1963,

20440-401: Was established around the ninth century, making it one of the oldest kingdoms in present-day Nigeri. The Nri kingdom is famous for its elaborate bronzes , found at the town of Igbo-Ukwu . The Kingdom of Ife , historically the first of these Yoruba city-states or kingdoms, established government under a priestly oba ('king' or 'ruler' in the Yoruba language ), called the Ooni of Ife . Ife

20586-404: Was found to be directly related to the bull shark conserving energy for itself. One way the bull shark is able to conserve energy is that when the tidal flow changes, the bull shark uses the tidal flow in order to conserve energy as it moves downriver. Another way for the bull shark to conserve energy is to decrease the amount of energy needed to osmoregulate the surrounding environment. Humans are

20732-450: Was fully established by roughly 500   BC in many areas of East and West Africa, although other regions did not begin ironworking until the early centuries AD. Copper objects from Egypt , North Africa, Nubia, and Ethiopia dating from around 500   BC have been excavated in West Africa, suggesting that Trans-Saharan trade networks had been established by this date. From 3500   BC, nomes (ruled by nomarchs ) coalesced to form

20878-474: Was independently invented in the region of Mali in the savannah of West Africa. In the steppes and savannahs of the Sahara and Sahel in Northern West Africa, people possibly ancestral to modern Nilo-Saharan and Mandé cultures started to collect wild millet , around 8,000 to 6,000   BC. Later, gourds , watermelons , castor beans , and cotton were also collected. Sorghum was first domesticated in Eastern Sudan around 4,000   BC, in one of

21024-444: Was noted as a major religious and cultural centre in West Africa and for its unique naturalistic tradition of bronze sculpture. The Ife model of government was adapted by the Oyo Empire , whose obas, called the Alaafins of Oyo , controlled many other Yoruba and non-Yoruba city-states and kingdoms including the Fon Kingdom of Dahomey . The Almoravids were a Berber dynasty from the Sahara that spread over northwestern Africa and

21170-514: Was one of the first African countries to gain independence, the state remained under the control of the country's white minority, initially through qualified voting rights and from 1956 by a system of racial segregation known as apartheid , until 1994. Today, Africa contains 54 sovereign countries. Since independence, African states have frequently been hampered by instability, corruption, violence, and authoritarianism. The vast majority of African states are republics that operate under some form of

21316-408: Was opened and all that was found were two small, unidentifiable fishes. The cause of death could have been starvation since the primary food source for bull sharks resides in salt water. In a research experiment, the bull sharks were found to be at the mouth of an estuary for the majority of the time. They stayed at the mouth of the river independent of the salinity of the water. The driving factor for

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