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Shark Attacks
A shark attack is an attack on a human by a shark. Every year, around 80 unprovoked attacks are reported worldwide. Despite their rarity, many people fear shark attacks after occasional serial attacks, such as the Jersey Shore shark attacks of 1916, and horror fiction and films such as the ''Jaws (film), Jaws'' series. Out of more than 500 List of sharks, shark species, only three are responsible for a double-digit number of fatal, unprovoked attacks on humans: the great white shark, great white, tiger shark, tiger, and bull shark, bull.ISAStatistics on Attacking Species of Shark/ref> The oceanic whitetip shark, oceanic whitetip has probably killed many more shipwreck and plane crash survivors, but these are not recorded in the statistics. Humans are not part of a shark's normal diet. Sharks usually feed on small fish and invertebrates, seals, sea lions, and other marine mammals. A shark attack will usually occur if the shark feels curious or confused. Terminology While the ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt Rock
Salt Rock is a small coastal village just north of Ballito and Shaka's Rock situated along the Dolphin Coast of KwaZulu-Natal, South Africa. It is a favorite holiday destination for many local South Africans. It is approximately located 52 kilometres (40 minutes) north-east of Durban and 19 km south-east of KwaDukuza. Salt Rock owes much of its history to Basil Hulett and his wife Gwen who started not only the Salt Rock Hotel but went on to develop the town of Salt Rock as found today. Geography Located approximately 7 kilometres (4 mi) north of Ballito, Salt Rock lies between Sheffield Beach to the north, Shaka’s Rock to the south, Simbithi Eco Estate to the south-west and Umhlali to the west. Residential development Over the past twenty years, there have been residential and commercial developments in the greater area of Salt Rock beyond the original village on previously sugarcane land. Developments of note include Brettenwood Coastal Estate (launche ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jersey Shore Shark Attacks Of 1916
The Jersey Shore shark attacks of 1916 were a series of shark attacks along the coast of New Jersey, in the United States, between July 1 and 12, 1916, in which four people were killed and one critically injured. The incidents occurred during a deadly summer heat wave and Poliomyelitis, polio epidemic in the United States that drove thousands of people to the seaside resorts of the Jersey Shore. Since 1916, scholars have debated which shark species was responsible and the number of animals involved, with the great white shark and the bull shark most frequently cited. Personal and national reaction to the fatalities involved a wave of panic that led to shark hunts aimed at eradicating the population of "man-eating" sharks and protecting the economies of New Jersey's seaside communities. Resort towns enclosed their public beaches with steel nets to protect swimmers. Scientific knowledge about sharks before 1916 was based on conjecture and speculation. The attacks forced Ichthyology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ampullae Of Lorenzini
Ampullae of Lorenzini (: ''ampulla'') are electroreceptors, sense organs able to detect electric fields. They form a network of mucus-filled pores in the skin of Chondrichthyes, cartilaginous fish (sharks, Ray (fish), rays, and chimaeras) and of basal Osteichthyes, bony fishes such as reedfish, sturgeon, and lungfish. They are associated with and evolved from the mechanosensory lateral line organs of early vertebrates. Most bony fishes and terrestrial vertebrates have lost their ampullae of Lorenzini. History Ampullae were initially described by Marcello Malpighi and later given an exact description by the Italian physician and ichthyologist Stefano Lorenzini in 1679, though their function was unknown. Electrophysiology, Electrophysiological experiments in the 20th century suggested a sensibility to temperature, mechanical pressure, and possibly salinity. In 1960 the ampullae were identified as specialized receptor organs for sensing electric fields. One of the first descriptio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orca
The orca (''Orcinus orca''), or killer whale, is a toothed whale and the largest member of the oceanic dolphin family. The only extant species in the genus '' Orcinus'', it is recognizable by its black-and-white-patterned body. A cosmopolitan species, it inhabits a wide range of marine environments, from Arctic to Antarctic regions to tropical seas. Orcas are apex predators with a diverse diet. Individual populations often specialize in particular types of prey, including fish, sharks, rays, and marine mammals such as seals, dolphins, and whales. They are highly social, with some populations forming stable matrilineal family groups (pods). Their sophisticated hunting techniques and vocal behaviors, often unique to specific groups and passed down from generation to generation, are considered to be manifestations of animal culture. The International Union for Conservation of Nature (IUCN) lists the orca's conservation status as data deficient as multiple orca types ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apex Predator
An apex predator, also known as a top predator or superpredator, is a predator at the top of a food chain, without natural predators of its own. Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic levels. Food chains are often far shorter on land, usually limited to being secondary consumers – for example, Gray wolf, wolves prey mostly upon large herbivores (primary consumers), which eat plants (primary producers). The apex predator concept is applied in wildlife management, conservation biology, conservation, and ecotourism. Apex predators have a long evolutionary history, dating at least to the Cambrian period when animals such as ''Anomalocaris'' and ''Timorebestia'' dominated the seas. Humans have for many centuries interacted with other apex predators including the wolf, Bird of prey, birds of prey, and cormorants to hunt game animals, birds, and fish respectively. More recently, humans have started interacting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Guardian
''The Guardian'' is a British daily newspaper. It was founded in Manchester in 1821 as ''The Manchester Guardian'' and changed its name in 1959, followed by a move to London. Along with its sister paper, ''The Guardian Weekly'', ''The Guardian'' is part of the Guardian Media Group, owned by the Scott Trust Limited. The trust was created in 1936 to "secure the financial and editorial independence of ''The Guardian'' in perpetuity and to safeguard the journalistic freedom and liberal values of ''The Guardian'' free from commercial or political interference". The trust was converted into a limited company in 2008, with a constitution written so as to maintain for ''The Guardian'' the same protections as were built into the structure of the Scott Trust by its creators. Profits are reinvested in its journalism rather than distributed to owners or shareholders. It is considered a newspaper of record in the UK. The editor-in-chief Katharine Viner succeeded Alan Rusbridger in 2015. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal Population Study
Population genetics is a subfield of genetics that deals with genetic differences within and among populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as adaptation, speciation, and population structure. Population genetics was a vital ingredient in the emergence of the modern evolutionary synthesis. Its primary founders were Sewall Wright, J. B. S. Haldane and Ronald Fisher, who also laid the foundations for the related discipline of quantitative genetics. Traditionally a highly mathematical discipline, modern population genetics encompasses theoretical, laboratory, and field work. Population genetic models are used both for statistical inference from DNA sequence data and for proof/disproof of concept. What sets population genetics apart from newer, more phenotypic approaches to modelling evolution, such as evolutionary game theory and adaptive dynamics, is its emphasis on such genetic phenomena as dominance, e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seal Island, South Africa
Seal Island (formerly known as ''Witte Klip'', meaning "White Rock") is a small land mass located off the northern beaches of False Bay, near Cape Town in South Africa. The island is so named because of the great number of Cape fur seals that occupy it. It is in area and home to 64,000 cape fur seals. Brown fur seals also live on the island. The large population of seals on the island previously attracted great white sharks to live in abundance near the island, but their population in the area began to drop in 2010, and they had disappeared from the area by 2018. It is not entirely known why great white sharks disappeared from the area, but it is believed to have been caused by either orcas or humans hunting them. The disappearance of great white sharks from the island caused the populations of broadnose sevengill sharks and seals to increase, as they lost their primary predator. References {{reflist External links Surface Pursuit of a Cape Fur Seal by a White Shark at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Research Vessel
A research vessel (RV or R/V) is a ship or boat designed, modified, or equipped to carry out research at sea. Research vessels carry out a number of roles. Some of these roles can be combined into a single vessel but others require a dedicated vessel. Due to the demanding nature of the work, research vessels may be constructed around an icebreaker hull, allowing them to operate in polar waters. History The research ship had origins in the early voyages of exploration. By the time of James Cook's ''Endeavour'', the essentials of what today we would call a research ship are clearly apparent. In 1766, the Royal Society hired Cook to travel to the Pacific Ocean to observe and record the transit of Venus across the Sun. The ''Endeavour'' was a sturdy vessel, well designed and equipped for the ordeals she would face, and fitted out with facilities for her "research personnel", Joseph Banks. As is common with contemporary research vessels, ''Endeavour'' also carried out more t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic Whitetip Shark
The oceanic whitetip shark (''Carcharhinus longimanus'') is a large requiem shark inhabiting the pelagic zone of tropical and warm temperate seas. It has a stocky body with its iconic elongated rounded fins, with white tips. The species is typically solitary, though they may gather in large numbers at food concentrations. Bony fish and cephalopods are the main components of its diet and females give live birth. Though slow-moving, the shark is opportunistic and aggressive, and is reputed to be dangerous to shipwreck survivors. The IUCN Red List considers the species to be critically endangered. As with other shark species, the whitetip faces mounting fishing pressure throughout its range, with recent studies show steeply declining populations as they are harvested for their fins and meat. Taxonomy The oceanic whitetip shark is known by many other english common names: Brown Milbert's sand bar shark, brown shark, shipwreck shark, nigano shark, oceanic white-tipped whale ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bull Shark
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 water, brackish and freshwater systems including estuaries and (usually) lower reach (geography), reaches of rivers. Their aggressive nature has led to ongoing shark-culling efforts near beaches to protect beachgoers, which is one of the causes of bull shark populations continuing to decrease. Bull sharks are listed as vulnerable on the IUCN Red List. Bull sharks are euryhaline and can thrive in both saltwater, 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 from the ocean, but few freshwater interactions with humans have been recorded. Larger-sized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tiger Shark
The tiger shark (''Galeocerdo cuvier'') is a species of ground shark, and the only extant member of the genus '' Galeocerdo'' and family Galeocerdonidae. It is a large apex predator, with females capable of attaining a length of over . Populations are found in many tropical and temperate waters, especially around central Pacific islands. Its name derives from the dark stripes down its body, which resemble a tiger's pattern, but fade as the shark matures. The tiger shark is a solitary, mostly nocturnal hunter. It is notable for having the widest food spectrum of all sharks, with a range of prey that includes crustaceans, fish, seals, birds, squid, turtles, sea snakes, dolphins, and others, even smaller sharks. It also has a reputation as a "garbage eater", consuming a variety of inedible, man-made objects that linger in its stomach. Tiger sharks have only one recorded natural predator, the orca. It is considered a near-threatened species because of finning and fishing by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
