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Whalesucker
The whalesucker (''Remora australis'') is a species of remora in the family Echeneidae, so named because it attaches itself exclusively to cetaceans. It is found worldwide in tropical and warm waters; in the Gulf of Mexico and western Atlantic Ocean, it occurs from Texas to Brazil, and in the eastern Pacific Ocean, it occurs from Vancouver Island to Chile. It is the rarest member of the remora family, though this may reflect more the uncommon collection of cetaceans in the wild rather than the whalesucker's actual abundance. The adhesive disk atop the head of the whalesucker is the largest amongst the remoras, bearing 25–28 Lamella (zoology), lamellae and measuring 47–59% of the standard length. The head itself measures 26–28% of the standard length. The dorsal fin rays number 23–26, the anal fin rays 24–26, and the pectoral fin rays 22–24. The jaws contain numerous large, stout canine teeth; the palatine and lingual patches are absent, and there are 17–20 gill raker ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remora
The remora (), sometimes called suckerfish, is any of a family (Echeneidae) of ray-finned fish in the order Carangiformes. Depending on species, they grow to long. Their distinctive first dorsal fins take the form of a modified oval, sucker-like organ with slat-like structures that open and close to create suction and take a firm hold against the skin of larger marine animals. The disk is made up of stout, flexible membranes that can be raised and lowered to generate suction. By sliding backward, the remora can increase the suction, or it can release itself by swimming forward. Remoras sometimes attach to small boats, and have been observed attaching to divers as well. They swim well on their own, with a sinuous, or curved, motion. Characteristics Remora front dorsal fins have evolved to enable them to adhere by suction to smooth surfaces, and they spend most of their lives clinging to a host animal such as a whale, turtle, shark or ray. It is probably a mutualistic arrang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echeneidae
The remora (), sometimes called suckerfish, is any of a family (Echeneidae) of ray-finned fish in the order Carangiformes. Depending on species, they grow to long. Their distinctive first dorsal fins take the form of a modified oval, sucker-like organ with slat-like structures that open and close to create suction and take a firm hold against the skin of larger marine animals. The disk is made up of stout, flexible membranes that can be raised and lowered to generate suction. By sliding backward, the remora can increase the suction, or it can release itself by swimming forward. Remoras sometimes attach to small boats, and have been observed attaching to divers as well. They swim well on their own, with a sinuous, or curved, motion. Characteristics Remora front dorsal fins have evolved to enable them to adhere by suction to smooth surfaces, and they spend most of their lives clinging to a host animal such as a whale, turtle, shark or ray. It is probably a mutualistic arrange ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederick Debell Bennett
Frederick Debell Bennett (1806 - 1859) was an English ship surgeon and biologist. Born to a family of means in Devon, England. in 1806, he obtained his Licentiate of the Society of Apothecaries (L.S.A.) in 182, and his membership of the Royal College of Surgeons in 1829. Bennett first served as Assistant Surgeon on the hospital ship Grampus, which was moored on the Thames. Then in 1833, he joined the London whaleship Tuscan. From 1833-1836 he sailed round the globe on board the 'Tuscan'. The task of this journey was to study whales, lands and nature. He described several species, for example Whalesucker (''Remora australis''), blue noddy and ''Cheilopogon nigricans''. He was also a member of the Royal Geographical Society. After his return he practiced medicine in Southwark where he died in 1859 at the age of fifty-three.Druett, Joan, Rough Medicine: Surgeons at Sea in the Age of Sail. New York: Routledge, 2001, pp. 40-41; 213. Book * Narrative of a Whaling Voyage Round the Globe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fernando De Noronha
Fernando de Noronha () is an archipelago in the Atlantic Ocean, part of the State of Pernambuco, Brazil, and located off the Brazilian coast. It consists of 21 islands and islets, extending over an area of . Only the eponymous main island is inhabited; it has an area of and a population estimated at 3,101 in 2020. While the archipelago is relatively low-lying, there are parts stretching above in elevation. The islands are administratively unique in Brazil. They form a "state district" ( pt, distrito estadual) that is administered directly by the government of the state of Pernambuco (despite being closer to the state of Rio Grande do Norte). The state district's jurisdiction also includes the very remote Saint Peter and Saint Paul Archipelago, located northeast of Fernando de Noronha. Seventy percent of the islands' area was established in 1988 as a national marine park. In 2001, UNESCO designated it as a World Heritage Site because of its importance as a feeding ground for t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drag (physics)
In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers (or surfaces) or between a fluid and a solid surface. Unlike other resistive forces, such as dry friction, which are nearly independent of velocity, the drag force depends on velocity. Drag force is proportional to the velocity for low-speed flow and the squared velocity for high speed flow, where the distinction between low and high speed is measured by the Reynolds number. Even though the ultimate cause of drag is viscous friction, turbulent drag is independent of viscosity. Drag forces always tend to decrease fluid velocity relative to the solid object in the fluid's path. Examples Examples of drag include the component of the net aerodynamic or hydrodynamic force acting opposite to the di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flotsam
In maritime law, flotsam'','' jetsam'','' lagan'','' and derelict are specific kinds of shipwreck. The words have specific nautical meanings, with legal consequences in the law of admiralty and marine salvage. A shipwreck is defined as the remains of a ship that has been wrecked—a destroyed ship at sea, whether it has sunk or is floating on the surface of the water. Overview A wreck is categorized as property belonging to no apparent owner that either sinks to the seabed or floats on the surface of the water, whether it be intentionally cast overboard or as the result of an accident. The term encompasses the hull of the vessel and its fixtures as well as any other form of object on board, such as cargo and stores, and personal effects of the crew and passengers. This also encompasses the narrower definition of salvage, that is, property that has been recovered from a wreckage, or the recovery of the ship itself. There are a number of factors that contribute to the formation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinner Dolphin
The spinner dolphin (''Stenella longirostris'') is a small dolphin found in off-shore tropical waters around the world. It is famous for its acrobatic displays in which it rotates around its longitudinal axis as it leaps through the air. It is a member of the family Delphinidae of toothed whales. Taxonomy The spinner dolphin is sometimes referred to as the long-snouted dolphin, particularly in older texts, to distinguish it from the similar Clymene dolphin, which is often called the short-snouted spinner dolphin. The species was described by John Gray in 1828. The four named subspecies are: *Eastern spinner dolphin (''S. l. orientalis''), from the tropical eastern Pacific. *Central American or Costa Rican spinner dolphin (''S. l. centroamericana''), also found in the tropical eastern Pacific. *Gray's or Hawaiian spinner dolphin (''S. l. longirostris''), from the central Pacific Ocean around Hawaii but represents a mixture of broadly similar subtypes found worldwide. *Dwarf spin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutualism (biology)
Mutualism describes the ecological interaction between two or more species where each species has a net benefit. Mutualism is a common type of ecological interaction. Prominent examples include most vascular plants engaged in mutualistic interactions with mycorrhizae, flowering plants being pollinated by animals, vascular plants being dispersed by animals, and corals with zooxanthellae, among many others. Mutualism can be contrasted with interspecific competition, in which each species experiences ''reduced'' fitness, and exploitation, or parasitism, in which one species benefits at the expense of the other. The term ''mutualism'' was introduced by Pierre-Joseph van Beneden in his 1876 book ''Animal Parasites and Messmates'' to mean "mutual aid among species". Mutualism is often conflated with two other types of ecological phenomena: cooperation and symbiosis. Cooperation most commonly refers to increases in fitness through within-species (intraspecific) interactions, althoug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stomach
The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach is involved in the gastric phase of digestion, following chewing. It performs a chemical breakdown by means of enzymes and hydrochloric acid. In humans and many other animals, the stomach is located between the oesophagus and the small intestine. The stomach secretes digestive enzymes and gastric acid to aid in food digestion. The pyloric sphincter controls the passage of partially digested food ( chyme) from the stomach into the duodenum, where peristalsis takes over to move this through the rest of intestines. Structure In the human digestive system, the stomach lies between the oesophagus and the duodenum (the first part of the small intestine). It is in the left upper quadrant of the abdominal cavity. The top of the stomach lies ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphipod
Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far described. They are mostly marine animals, but are found in almost all aquatic environments. Some 1,900 species live in fresh water, and the order also includes the terrestrial sandhoppers such as ''Talitrus saltator''. Etymology and names The name ''Amphipoda'' comes, via New Latin ', from the Greek roots 'on both/all sides' and 'foot'. This contrasts with the related Isopoda, which have a single kind of thoracic leg. Particularly among anglers, amphipods are known as ''freshwater shrimp'', ''scuds'', or ''sideswimmers''. Description Anatomy The body of an amphipod is divided into 13 segments, which can be grouped into a head, a thorax and an abdomen. The head is fused to the thorax, and bears two pairs of antennae and one pair of se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copepod
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (inhabiting sea waters), some are benthos, benthic (living on the ocean floor), a number of species have parasitic phases, and some continental species may live in limnoterrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds, and puddles, damp moss, or water-filled recesses (phytotelmata) of plants such as bromeliads and pitcher plants. Many live underground in marine and freshwater caves, sinkholes, or stream beds. Copepods are sometimes used as Ecological indicator, biodiversity indicators. As with other crustaceans, copepods have a larval form. For copepods, the egg hatches into a Crustacean larvae#Nauplius, nauplius form, with a head and a tail but no true thorax or abdomen. The larva molts several times until it resembles the adult an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitism
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as Armillaria mellea, honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the Orobanchaceae, broomrapes. There are six major parasitic Behavioral ecology#Evolutionarily stable strategy, strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), wikt:trophic, trophicallytransmitted parasitism (by being eaten), Disease vector, vector-transmitted paras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
