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66-652: The municipal seat is located in Santa Rosalía . The El Vizcaíno Biosphere Reserve is located in the municipality, between the Pacific Ocean and the Gulf of California. With a landmass of over 24,930 km (9,625 sq mi), it is the largest wildlife refuge in Mexico and borders on the northern edge of the Valle de los Cirios Protected Area of Flora and Fauna. Juan Rodríguez Cabrillo was

132-426: A heterocercal caudal fin in which the dorsal portion is usually noticeably larger than the ventral portion. This is because the shark's vertebral column extends into that dorsal portion, providing a greater surface area for muscle attachment. This allows more efficient locomotion among these negatively buoyant cartilaginous fish. By contrast, most bony fish possess a homocercal caudal fin. Tiger sharks have

198-487: A Korean Consortium began developing the $ 1.6 Billion project in 2010. In 2012 however, construction cost overruns reported by Baja Mining threatened to halt or delay construction of the project. Majority ownership interest and control of the project was transferred to the Korean consortium, in return for funding the reported cost overruns. On January 26, 2015 Minera y Metalurgica del Boleo obtained its first copper production from

264-415: A cell similar to hair cells present in the vertebrate ear that interact with the surrounding aquatic environment. This helps sharks distinguish between the currents around them, obstacles off on their periphery, and struggling prey out of visual view. The shark can sense frequencies in the range of 25 to 50  Hz . Shark lifespans vary by species. Most live 20 to 30 years. The spiny dogfish has one of

330-418: A constant supply of oxygenated water. A small number of species have lost the ability to pump water through their gills and must swim without rest. These species are obligate ram ventilators and would presumably asphyxiate if unable to move. Obligate ram ventilation is also true of some pelagic bony fish species. The respiratory and circulatory process begins when deoxygenated venous blood travels to

396-495: A few known exceptions, such as the bull shark and the river sharks , which can be found in both seawater and freshwater, and the Ganges shark , which lives only in freshwater. Sharks have a covering of dermal denticles that protects their skin from damage and parasites in addition to improving their fluid dynamics . They have numerous sets of replaceable teeth. Several species are apex predators , which are organisms that are at

462-509: A group of elasmobranch fish characterized by a cartilaginous skeleton , five to seven gill slits on the sides of the head , and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii ) and are the sister group to the Batoidea ( rays and kin). Some sources extend the term "shark" as an informal category including extinct members of Chondrichthyes (cartilaginous fish) with

528-423: A large upper lobe , which allows for slow cruising and sudden bursts of speed. The tiger shark must be able to twist and turn in the water easily when hunting to support its varied diet, whereas the porbeagle shark , which hunts schooling fish such as mackerel and herring , has a large lower lobe to help it keep pace with its fast-swimming prey. Other tail adaptations help sharks catch prey more directly, such as

594-438: A long surface area, requiring food to circulate inside the short gut until fully digested, when remaining waste products pass into the cloaca . A few sharks appear fluorescent under blue light, such as the swell shark and the chain catshark , where the fluorophore derives from a metabolite of kynurenic acid . Sharks have keen olfactory senses, located in the short duct (which is not fused, unlike bony fish) between

660-445: A row behind the head. A modified slit called a spiracle lies just behind the eye, which assists the shark with taking in water during respiration and plays a major role in bottom–dwelling sharks. Spiracles are reduced or missing in active pelagic sharks. While the shark is moving, water passes through the mouth and over the gills in a process known as "ram ventilation". While at rest, most sharks pump water over their gills to ensure

726-596: A shark-like morphology, such as hybodonts . Shark-like chondrichthyans such as Cladoselache and Doliodus first appeared in the Devonian Period (419–359 million years), though some fossilized chondrichthyan-like scales are as old as the Late Ordovician (458–444 million years ago). The earliest confirmed modern sharks (selachimorphs) are known from the Early Jurassic around 200  million years ago , with

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792-405: A similar mechanism for maintaining an elevated body temperature. Larger species, like the whale shark, are able to conserve their body heat through sheer size when they dive to colder depths, and the scalloped hammerhead close its mouth and gills when they dives to depths of around 800 metres, holding its breath till it reach warmer waters again. In contrast to bony fish, with the exception of

858-555: A single type of cone photoreceptor sensitive to green and, seeing only in shades of grey and green, are believed to be effectively colorblind. The study indicates that an object's contrast against the background, rather than colour, may be more important for object detection. Although it is hard to test the hearing of sharks, they may have a sharp sense of hearing and can possibly hear prey from many miles away. The hearing sensitivity for most shark species lies between 20 and 1000 Hz. A small opening on each side of their heads (not

924-400: A tissue called tapetum lucidum . This tissue is behind the retina and reflects light back to it, thereby increasing visibility in the dark waters. The effectiveness of the tissue varies, with some sharks having stronger nocturnal adaptations. Many sharks can contract and dilate their pupils , like humans, something no teleost fish can do. Sharks have eyelids, but they do not blink because

990-444: Is an unusual sediment-hosted copper- cobalt - zinc -manganese ore deposit. Seven large manto ore deposits have been identified. El Boleo was mined by Compagnie du Boleo, a French company, from 1885 until 1954. To prevent the economic collapse of Santa Rosalia and surrounding communities, a Mexican state-owned company (CMSRSA) assumed control and reopened the works using basically the same (rather archaic) equipment and process used by

1056-714: Is concentrated around the production of salt in Guerrero Negro (4.8 million tons), plaster in San Marcos Island (1.3 million ton) and copper in Santa Rosalía (11 thousand tons), and employs 21.6 % of the population. The fishing sector employs 10.6 % of the population. There were 19,329 tons of fish products in 2021, of which fish represented more than 62 % of the captures. Other products include lobsters , sharks , shellfish and octopus . There also processing centers of lobster , abalone , snail and mackerel . The tourism sector has been growing in

1122-710: Is crossed by the Carretera Transpeninsular ( Mexican Federal Highway 1 ), which runs from Tijuana to Cabo San Lucas . Regional flights are available at the Palo Verde Airport in Santa Rosalía. 27°15′N 113°15′W  /  27.250°N 113.250°W  / 27.250; -113.250 Santa Rosal%C3%ADa, Baja California Sur Santa Rosalía is a city and municipal seat of Mulegé Municipality , in Baja California Sur , situated along

1188-648: Is debated. Some believe that electro- and chemoreception are more significant, while others point to the nictating membrane as evidence that sight is important, since presumably the shark would not protect its eyes were they unimportant. The use of sight probably varies with species and water conditions. The shark's field of vision can swap between monocular and stereoscopic at any time. A micro-spectrophotometry study of 17 species of sharks found 10 had only rod photoreceptors and no cone cells in their retinas giving them good night vision while making them colorblind . The remaining seven species had in addition to rods

1254-668: Is divided into the superorders Galea (or Galeomorphii ), and Squalea (or Squalomorphii ). The Galeans are the Heterodontiformes , Orectolobiformes , Lamniformes , and Carcharhiniformes . Lamnoids and Carcharhinoids are usually placed in one clade , but recent studies show that Lamnoids and Orectoloboids are a clade. Some scientists now think that Heterodontoids may be Squalean. The Squaleans are divided into Hexanchiformes and Squalomorpha. The former includes cow shark and frilled shark , though some authors propose that both families be moved to separate orders. The Squalomorpha contains

1320-409: Is high, species of sharks from the family Carcharhinidae have smaller olfactory bulbs. Sharks found in deeper waters also have larger olfactory bulbs. Sharks have the ability to determine the direction of a given scent based on the timing of scent detection in each nostril. This is similar to the method mammals use to determine direction of sound. They are more attracted to the chemicals found in

1386-421: Is in original location Mulegé , about 100 km (62 mi) south. Santa Rosalía boasts French influence, particularly in its architecture. The French Compagnie du Boleo founded the town in 1884 and exploited copper mines there until they closed in 1954. They built houses and installed the metallic Iglesia de Santa Bárbara . Unlike many other mining sites, the industrial facilities which are located in

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1452-581: Is limited, so sharks employ dynamic lift to maintain depth while swimming. Sand tiger sharks store air in their stomachs, using it as a form of swim bladder. Bottom-dwelling sharks, like the nurse shark , have negative buoyancy, allowing them to rest on the ocean floor. Some sharks, if inverted or stroked on the nose, enter a natural state of tonic immobility . Researchers use this condition to handle sharks safely. Like other fish, sharks extract oxygen from seawater as it passes over their gills . Unlike other fish, shark gill slits are not covered, but lie in

1518-434: Is observed in the cookiecutter shark . Tooth shape depends on the shark's diet: those that feed on mollusks and crustaceans have dense and flattened teeth used for crushing, those that feed on fish have needle-like teeth for gripping, and those that feed on larger prey such as mammals have pointed lower teeth for gripping and triangular upper teeth with serrated edges for cutting. The teeth of plankton-feeders such as

1584-492: Is still evidential in several species termed " dogfish ," or the porbeagle . The etymology of the word shark is uncertain. The most likely etymology states that the original sense of the word was that of "predator, one who preys on others" from the Dutch schurk , meaning 'villain, scoundrel' ( cf. card shark , loan shark , etc.), which was later applied to the fish due to its predatory behaviour. A now disproven theory

1650-736: Is that it derives from the Yucatec Maya word xook ( pronounced [ʃoːk] ), meaning 'shark'. Evidence for this etymology came from the Oxford English Dictionary , which notes that shark first came into use after Sir John Hawkins ' sailors exhibited one in London in 1569 and posted " sharke " to refer to the large sharks of the Caribbean Sea . However, the Middle English Dictionary records an isolated occurrence of

1716-665: The Devonian . Anachronistidae , the oldest probable representatives of Neoselachii, the group containing modern sharks (Selachimorpha) and rays (Batoidea) to the exclusion of most extinct elasmobranch groups, date to the Carboniferous . Selachiimorpha and Batoidea are suggested by some to have diverged during the Triassic . Fossils of the earliest true sharks may have appeared during the Permian , based on remains of " synechodontiforms " found in

1782-570: The Gulf of California . Located on the east coast of the Baja Peninsula , the town had a population of 14,357 inhabitants in 2020. The city was founded as a company town by the French Compagnie du Boleo in 1884, which established the local copper mines. Today the city is a popular tourist destination. The town was named after Saint Rosalia , although the mission is not located by the town, but

1848-704: The Squaliformes and the Hypnosqualea. The Hypnosqualea may be invalid. It includes the Squatiniformes , and the Pristorajea, which may also be invalid, but includes the Pristiophoriformes and the Batoidea . There are more than 500 species of sharks split across thirteen orders , including several orders of sharks that have gone extinct: Shark teeth are embedded in the gums rather than directly affixed to

1914-463: The bull shark , which has developed a way to change its kidney function to excrete large amounts of urea. When a shark dies, the urea is broken down to ammonia by bacteria, causing the dead body to gradually smell strongly of ammonia. Research in 1930 by Homer W. Smith showed that sharks' urine does not contain sufficient sodium to avoid hypernatremia , and it was postulated that there must be an additional mechanism for salt secretion. In 1960 it

1980-504: The clade Selachimorpha in the subclass Elasmobranchii in the class Chondrichthyes . The Elasmobranchii also include rays and skates ; the Chondrichthyes also include Chimaeras . It was thought that the sharks form a polyphyletic group: some sharks are more closely related to rays than they are to some other sharks, but current molecular studies support monophyly of both groups of sharks and batoids. The clade Selachimorpha

2046-441: The coelacanth , the blood and other tissue of sharks and Chondrichthyes is generally isotonic to their marine environments because of the high concentration of urea (up to 2.5% ) and trimethylamine N-oxide (TMAO), allowing them to be in osmotic balance with the seawater. This adaptation prevents most sharks from surviving in freshwater, and they are therefore confined to marine environments. A few exceptions exist, such as

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2112-461: The cranium . The jaw's surface (in comparison to the shark's vertebrae and gill arches) needs extra support due to its heavy exposure to physical stress and its need for strength. It has a layer of tiny hexagonal plates called " tesserae ", which are crystal blocks of calcium salts arranged as a mosaic. This gives these areas much of the same strength found in the bony tissue found in other animals. Generally sharks have only one layer of tesserae, but

2178-452: The electric fields they produce. Ocean currents moving in the magnetic field of the Earth also generate electric fields that sharks can use for orientation and possibly navigation. This system is found in most fish, including sharks. It is a tactile sensory system which allows the organism to detect water speed and pressure changes near by. The main component of the system is the neuromast,

2244-414: The great white shark ) are homeothermic and maintain a higher body temperature than the surrounding water. In these sharks, a strip of aerobic red muscle located near the center of the body generates the heat, which the body retains via a countercurrent exchange mechanism by a system of blood vessels called the rete mirabile ("miraculous net"). The common thresher and bigeye thresher sharks have

2310-1036: The Early Permian of Russia, but if remains of "synechodontiformes" from the Permian and Triassic are true sharks, they only had low diversity. Modern shark orders first appeared during the Early Jurassic, and during the Jurassic true sharks underwent great diversification. Selachimorphs largely replaced the hybodonts , which had previously been a dominant group of shark-like fish during the Triassic and Early Jurassic. Batoidea [REDACTED] Heterodontiformes [REDACTED] Orectolobiformes [REDACTED] Carcharhiniformes [REDACTED] Lamniformes [REDACTED] Hexanchiformes [REDACTED] Squatiniformes [REDACTED] Pristiophoriformes [REDACTED] Squaliformes [REDACTED] Sharks belong to

2376-582: The Franciscans took over responsibility for colonial Baja California from the Jesuits. Rich copper deposits were discovered in 1868, later developed as mines. In 1872, Eiseman y Valle was incorporated as a business for the exploitation of copper. In 1885, the French mining company El Boleo began its operations and built the town of Santa Rosalía; the first copper smelting furnace was installed in 1886. The municipality

2442-599: The French. The government funded operation was never profitable, and the mine was finally closed in the 1980s, when lower-grade ore and old technology made continued operation impractical. Baja Mining, a Canadian firm, began intermittent exploration of the El Boleo mine and subsequently undertook an effort to reopen El Boleo. Baja Mining estimated that the property contains a resource of 534 million tons of ore, containing 0.59% Cu, 0.051% Co, and 0.63% Zn. Baja also hoped to produce byproduct manganese . Baja Mining, in partnership with

2508-566: The Gulf of California side, which includes Santa Rosalía and Mulegé. As of March 1, 2021, the municipality reported 1,188 recoveries, 46 active cases, and 109 deaths from the COVID-19 pandemic in Mexico . Including the municipal seat of Santa Rosalía, the municipality is subdivided into six delegaciones : There are four main economic sectors in Mulegé: agriculture, mining, livestock and tourism. Agriculture and livestock are principally concentrated in

2574-417: The anterior and posterior nasal openings, with some species able to detect as little as one part per million of blood in seawater. The size of the olfactory bulb varies across different shark species, with size dependent on how much a given species relies on smell or vision to find their prey. In environments with low visibility, shark species generally have larger olfactory bulbs. In reefs, where visibility

2640-436: The area of Vizcaíno Valley and employs 36% of the population. There were 2,987.7 ha of crop land in the municipality. The main crops are tomatoes , chili peppers , onions , cucumbers , strawberries and figs . The meat production comes principally from cattle (697.8 tons), pigs (117.6 tons), goats (14.9 tons) and sheep (11 tons). There is also a significant production of milk from goats and cows. The mining sector

2706-568: The basking shark are small and non-functional. Shark skeletons are very different from those of bony fish and terrestrial vertebrates . Sharks and other cartilaginous fish ( skates and rays ) have skeletons made of cartilage and connective tissue . Cartilage is flexible and durable, yet is about half the normal density of bone. This reduces the skeleton's weight, saving energy. Because sharks do not have rib cages, they can easily be crushed under their own weight on land. The jaws of sharks, like those of rays and skates, are not attached to

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2772-416: The body then flows through the posterior cardinal veins and enters the posterior cardinal sinuses . From there venous blood re-enters the heart ventricle and the cycle repeats. Most sharks are "cold-blooded" or, more precisely, poikilothermic , meaning that their internal body temperature matches that of their ambient environment. Members of the family Lamnidae (such as the shortfin mako shark and

2838-640: The first explorer to navigate the coastline of Mulegé, whereas Sebastián Vizcaíno explored the inlands in 1596 on behalf of Gaspar de Zúñiga , viceroy of New Spain . The first Spanish missionary to visit the area was Father Juan María de Salvatierra in 1705. Three years later, the Jesuit missionary Juan de Basaldúa founded the Santa Rosalía de Mulegé mission in the area locally known as Caaman Cagaleja, which means "river between two rocks." Other important Jesuit missions in Mulegé were San Ignacio and Guadalupe . In 1768,

2904-1168: The horny keratin in hair and feathers. Most sharks have eight fins. Sharks can only drift away from objects directly in front of them because their fins do not allow them to move in the tail-first direction. Unlike bony fish, sharks have a complex dermal corset made of flexible collagenous fibers and arranged as a helical network surrounding their body. This works as an outer skeleton, providing attachment for their swimming muscles and thus saving energy. Their dermal teeth give them hydrodynamic advantages as they reduce turbulence when swimming. Some species of shark have pigmented denticles that form complex patterns like spots (e.g. Zebra shark ) and stripes (e.g. Tiger shark ). These markings are important for camouflage and help sharks blend in with their environment, as well as making them difficult for prey to detect. For some species, dermal patterning returns to healed denticles even after they have been removed by injury. Tails provide thrust, making speed and acceleration dependent on tail shape. Caudal fin shapes vary considerably between shark species, due to their evolution in separate environments. Sharks possess

2970-418: The inner ear has been lost. The ampullae of Lorenzini are the electroreceptor organs. They number in the hundreds to thousands. Sharks use the ampullae of Lorenzini to detect the electromagnetic fields that all living things produce. This helps sharks (particularly the hammerhead shark ) find prey. The shark has the greatest electrical sensitivity of any animal. Sharks find prey hidden in sand by detecting

3036-402: The intestines of many species, and as a result often linger near or in sewage outfalls. Some species, such as nurse sharks , have external barbels that greatly increase their ability to sense prey. Shark eyes are similar to the eyes of other vertebrates , including similar lenses , corneas and retinas , though their eyesight is well adapted to the marine environment with the help of

3102-451: The jaw, and are constantly replaced throughout life. Multiple rows of replacement teeth grow in a groove on the inside of the jaw and steadily move forward in comparison to a conveyor belt ; some sharks lose 30,000 or more teeth in their lifetime. The rate of tooth replacement varies from once every 8 to 10 days to several months. In most species, teeth are replaced one at a time as opposed to the simultaneous replacement of an entire row, which

3168-453: The jaws of large specimens, such as the bull shark, tiger shark, and the great white shark, have two to three layers or more, depending on body size. The jaws of a large great white shark may have up to five layers. In the rostrum (snout), the cartilage can be spongy and flexible to absorb the power of impacts. Fin skeletons are elongated and supported with soft and unsegmented rays named ceratotrichia, filaments of elastic protein resembling

3234-415: The largest of which (with 2020 populations in parentheses) were: Santa Rosalía (14,357 hab.), Guerrero Negro (13,596 hab.), Villa Alberto Andrés Alvarado Arámburo (10,897 hab.), Mulegé (3,834 hab.), Bahía Tortugas (2,367 hab.), classified as urban; and San Francisco (1,919 hab.), Bahía Asunción (1,453 hab.), Las Margaritas (1,145 hab.), and Estero de la Bocana (1,013 hab.), classified as rural. Mulegé

3300-535: The last years. The municipality is home of two jesuit missions of the XVII century in Mulegé and San Ignacio , these two towns also have oasis, which are a popular sightview in the desert. Santa Rosalía it's another spot, famous for being an historical mining town and their many buildings in french architectural style. Ecotourism revolves around whale watching of gray whales at San Ignacio Lagoon and Guerrero Negro during

3366-538: The longest lifespans at more than 100 years. Whale sharks ( Rhincodon typus ) may also live over 100 years. Earlier estimates suggested the Greenland shark ( Somniosus microcephalus ) could reach about 200 years, but a recent study found that a 5.02-metre-long (16.5 ft) specimen was 392 ± 120 years old (i.e., at least 272 years old), making it the longest-lived vertebrate known. Unlike most bony fish , sharks are K-selected reproducers, meaning that they produce

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3432-516: The months of December to April. Mulegé also has many popular beaches, many of which are nearby Mulegé town. Mulegé also contains the most famous rock art sites in Baja California Sur and Mexico. The best known sites are located at Sierra de San Francisco , although many of them requires trips by mule of 3-5 days. There are minor sites at Sierra de Guadalupe , nearby Mulegé , which can be reached by car. The municipality has 381 localities,

3498-553: The oldest known member being Agaleus , though records of true sharks may extend back as far as the Permian . Sharks range in size from the small dwarf lanternshark ( Etmopterus perryi ), a deep sea species that is only 17 centimetres (6.7 in) in length, to the whale shark ( Rhincodon typus ), the largest fish in the world, which reaches approximately 12 metres (40 ft) in length. They are found in all seas and are common to depths up to 2,000 metres (6,600 ft). They generally do not live in freshwater, although there are

3564-435: The process of crushing, leaching, extracting and electrowinning in its mine-metallurgic project "El Boleo". Santa Rosalía is a port city, and a regular ferry connects with Guaymas , Sonora , on the other side of the Gulf of California . At the Palo Verde Airport daily flights are available from Guaymas and twice a week from Hermosillo , Sonora . It is located along Mexican Federal Highway 1 . Due to its location in

3630-403: The shark's two-chambered heart . Here, the shark pumps blood to its gills via the ventral aorta where it branches into afferent branchial arteries . Gas exchange takes place in the gills and the reoxygenated blood flows into the efferent branchial arteries, which come together to form the dorsal aorta . The blood flows from the dorsal aorta throughout the body. The deoxygenated blood from

3696-413: The spiracle) leads directly into the inner ear through a thin channel. The lateral line shows a similar arrangement, and is open to the environment via a series of openings called lateral line pores . This is a reminder of the common origin of these two vibration- and sound-detecting organs that are grouped together as the acoustico-lateralis system. In bony fish and tetrapods the external opening into

3762-414: The stomach, and instead the shark either vomits or turns its stomachs inside out and ejects unwanted items from its mouth. One of the biggest differences between the digestive systems of sharks and mammals is that sharks have much shorter intestines. This short length is achieved by the spiral valve with multiple turns within a single short section instead of a long tube-like intestine. The valve provides

3828-423: The surrounding water cleans their eyes. To protect their eyes some species have nictitating membranes . This membrane covers the eyes while hunting and when the shark is being attacked. However, some species, including the great white shark ( Carcharodon carcharias ), do not have this membrane, but instead roll their eyes backwards to protect them when striking prey. The importance of sight in shark hunting behavior

3894-403: The thresher shark's usage of its powerful, elongated upper lobe to stun fish and squid. Unlike bony fish, sharks do not have gas-filled swim bladders for buoyancy. Instead, sharks rely on a large liver filled with oil that contains squalene , and their cartilage, which is about half the normal density of bone. Their liver constitutes up to 30% of their total body mass. The liver's effectiveness

3960-456: The top of their food chain . Select examples include the bull shark , tiger shark , great white shark , mako sharks , thresher sharks , and hammerhead sharks . Sharks are caught by humans for shark meat or shark fin soup . Many shark populations are threatened by human activities. Since 1970, shark populations have been reduced by 71%, mostly from overfishing . Until the 16th century, sharks were known to mariners as "sea dogs". This

4026-473: The very middle of the town, were never dismantled. Of particular interest are the reverberatory furnace and the metallurgical converter , although they are currently not accessible by the public due to safety concerns. Old locomotives , mining equipment and machinery are visible everywhere, much preserved as ornate. The main mining company building (La dirección) have been reconverted into the city hall and its offices into an industrial museum. The Boleo Mine

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4092-571: The warm Gulf waters, which are considerably warmer than Pacific waters in the winter, the town is the northernmost (and thus closest to the US border) year-round warm locale on the main peninsular highway. Nevertheless, it's not much of a tourist town and sees few snowbirds. The 2020 census showed a population of 14,357 persons. The population was 10,190 in 1990. 27°20′20″N 112°16′01″W  /  27.33889°N 112.26694°W  / 27.33889; -112.26694 Sharks Sharks are

4158-541: The word shark (referring to a sea fish) in a letter written by Thomas Beckington in 1442, which rules out a New World etymology. The oldest total-group chondrichthyans, known as acanthodians or "spiny sharks", appeared during the Early Silurian , around 439 million years ago. The oldest confirmed members of Elasmobranchii sensu lato (the group containing all cartilaginous fish more closely related to modern sharks and rays than to chimaeras ) appeared during

4224-553: Was discovered at the Mount Desert Island Biological Laboratory in Salsbury Cove, Maine that sharks have a type of salt gland located at the end of the intestine, known as the "rectal gland", whose function is the secretion of chlorides. Digestion can take a long time. The food moves from the mouth to a J-shaped stomach, where it is stored and initial digestion occurs. Unwanted items may never get past

4290-488: Was first incorporated in 1916 as part of the Baja California Territory , Southern District. In 1929, the municipal council was replaced by a municipal delegation. By 1954, the mining company "El Boleo" ceased operations, which resulted in many people moving to other parts of the country, but three years later, Fomento Minero decided to take over the company and restarted the copper exploitation work. Guerrero Negro

4356-494: Was founded in 1957 on the Pacific Coast to supply the demand of salt in the western United States. When Baja California Sur became a state in 1972, the municipality of Mulegé was formally established. There is an initiative to split the municipality into two, with the division along the ridge dividing the current municipality. The Pacific side, with Guerrero Negro and Villa Alberto Andrés Alvarado Arámburo would be separated from

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