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Culpepper Island (Galápagos)
Darwin Island (Spanish: ''Isla Darwin'') is among the smallest in the Galápagos Archipelago with an area of just . It is named in honour of English scientist Charles Darwin. With no dry landing sites, Darwin Island's main attractions are found in the Pacific Ocean, which is teeming with a large variety of marine life. Although the island had been marked on maps and had initially been given the name Culpepper Island on Admiralty charts, the first landing on Darwin Island was not until 1964, by helicopter. The small detached group formed by Darwin Island and Wolf Island is sometimes referred to as Darwin and Wolf or Darwin-Wolf, formerly Culpepper and Wenman. Geology Darwin Island is the remains of an extinct volcano that reaches above sea level. It is situated north-west of the main Galápagos Island group on the Wolf-Darwin Lineament, which extends from the Galápagos Platform to the Galápagos Spreading Centre, a mid-ocean ridge separating the Nazca and Cocos tectonic p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galápagos Islands
The Galápagos Islands (Spanish: , , ) are an archipelago of volcanic islands. They are distributed on each side of the equator in the Pacific Ocean, surrounding the centre of the Western Hemisphere, and are part of the Republic of Ecuador. Located west of continental Ecuador, the islands are known for their large number of endemic species that were studied by Charles Darwin during the second voyage of HMS ''Beagle''. His observations and collections contributed to the inception of Darwin's theory of evolution by means of natural selection. The Galápagos Islands and their surrounding waters form the Galápagos Province of Ecuador, the Galápagos National Park, and the Galápagos Marine Reserve. The principal language on the islands is Spanish. The islands have a population of slightly over 25,000. The first recorded visit to the islands happened by chance in 1535, when Fray Tomás de Berlanga, the Bishop of Panamá, was surprised to find this undiscovered land on a vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vampire Finch
The vampire ground finch (''Geospiza septentrionalis'') is a small bird native to the Galápagos Islands. It was considered a very distinct subspecies of the sharp-beaked ground finch (''Geospiza difficilis'') endemic to Wolf and Darwin Islands.Grant, Peter R.; Grant, B. Rosemary & Petren, Kenneth (2000). The allopatric phase of speciation: the sharp-beaked ground finch (''Geospiza difficilis'') on the Galápagos islands. '' Biol. J. Linn. Soc.'' 69(3): 287–317. The International Ornithologists' Union has split the species supported by strong genetic evidence that they are not closely related, and divergences in morphology and song. Other taxonomic authorities still consider it conspecific. Description The vampire finch is sexually dimorphic as typical for its genus, with the males being primarily black and the females grey with brown streaks. It has a lilting song on Wolf, a buzzing song on Darwin, and whistling calls on both islands; only on Wolf, a drawn-out, buzzing call i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red-footed Booby
The red-footed booby (''Sula sula'') is a large seabird of the booby family, Sulidae. Adults always have red feet, but the colour of the plumage varies. They are powerful and agile fliers, but they are clumsy in takeoffs and landings. They are found widely in the tropics, and breed colonially in coastal regions, especially islands. The species faces few natural or man-made threats, although its population is declining; it is considered to be a least-concern species by the International Union for Conservation of Nature (IUCN). Taxonomy The first formal description of the red-footed booby was by the Swedish naturalist Carl Linnaeus in 1766 in the twelfth edition of his ''Systema Naturae''. He introduced the binomial name ''Pelecanus sula''. The type locality is Barbados in the West Indies. The present genus ''Sula'' was introduced by the French scientist Mathurin Jacques Brisson in 1760. The word ''Sula'' is Norwegian for a gannet. There are three subspecies: * ''S. s. sula'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frigatebird
Frigatebirds are a family of seabirds called Fregatidae which are found across all tropical and subtropical oceans. The five extant species are classified in a single genus, ''Fregata''. All have predominantly black plumage, long, deeply forked tails and long hooked bills. Females have white underbellies and males have a distinctive red gular pouch, which they inflate during the breeding season to attract females. Their wings are long and pointed and can span up to , the largest wing area to body weight ratio of any bird. Able to soar for weeks on wind currents, frigatebirds spend most of the day in flight hunting for food, and roost on trees or cliffs at night. Their main prey are fish and squid, caught when chased to the water surface by large predators such as tuna. Frigatebirds are referred to as kleptoparasites as they occasionally rob other seabirds for food, and are known to snatch seabird chicks from the nest. Seasonally monogamous, frigatebirds nest colonially. A roug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolphin
A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the brackish dolphins), and the extinct Lipotidae (baiji or Chinese river dolphin). There are 40 extant species named as dolphins. Dolphins range in size from the and Maui's dolphin to the and orca. Various species of dolphins exhibit sexual dimorphism where the males are larger than females. They have streamlined bodies and two limbs that are modified into flippers. Though not quite as flexible as seals, some dolphins can briefly travel at speeds of per hour or leap about . Dolphins use their conical teeth to capture fast-moving prey. They have well-developed hearing which is adapted for both air and water. It is so well developed that some can survive even if they are blind. Some species are well adapted for diving to great depths. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manta Ray
Manta rays are large rays belonging to the genus ''Mobula'' (formerly its own genus ''Manta''). The larger species, '' M. birostris'', reaches in width, while the smaller, '' M. alfredi'', reaches . Both have triangular Pectoral fin#AnchPectoral, pectoral fins, horn-shaped cephalic fins and large, forward-facing mouths. They are classified among the Myliobatiformes (stingrays and relatives) and are placed in the Family (biology), family Myliobatidae (eagle rays). They have the largest brains and brain to body ratio of all fish, and can pass the mirror test. Mantas are found in warm temperate, subtropical and tropical waters. Both species are Pelagic fish, pelagic; ''M. birostris'' Animal migration, migrates across open oceans, singly or in groups, while ''M. alfredi'' tends to be resident and coastal. They are filter feeders and eat large quantities of zooplankton, which they gather with their open mouths as they swim. However, research suggests that the majority of their die ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Turtles
The green sea turtle (''Chelonia mydas''), also known as the green turtle, black (sea) turtle or Pacific green turtle, is a species of large sea turtle of the family Cheloniidae. It is the only species in the genus ''Chelonia''. Its range extends throughout tropical and subtropical seas around the world, with two distinct populations in the Atlantic and Pacific Oceans, but it is also found in the Indian Ocean. The common name refers to the usually green fat found beneath its carapace, not to the color of its carapace, which is olive to black. The dorsoventrally flattened body of ''C. mydas'' is covered by a large, teardrop-shaped carapace; it has a pair of large, paddle-like flippers. It is usually lightly colored, although in the eastern Pacific populations, parts of the carapace can be almost black. Unlike other members of its family, such as the hawksbill sea turtle, ''C. mydas'' is mostly herbivorous. The adults usually inhabit shallow lagoons, feeding mostly on various spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blacktip Shark
The blacktip shark (''Carcharhinus limbatus'') is a species of requiem shark, and part of the family Carcharhinidae. It is common to coastal tropical and subtropical waters around the world, including brackish habitats. Genetic analyses have revealed substantial variation within this species, with populations from the western Atlantic Ocean isolated and distinct from those in the rest of its range. The blacktip shark has a stout, fusiform body with a pointed snout, long gill slits, and no ridge between the dorsal fins. Most individuals have black tips or edges on the pectoral, dorsal, pelvic, and caudal fins. It usually attains a length of . Swift, energetic piscivores, blacktip sharks are known to make spinning leaps out of the water while attacking schools of small fish. Their demeanor has been described as "timid" compared to other large requiem sharks. Both juveniles and adults form groups of varying size. Like other members of its family, the blacktip shark is viviparous; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silky Shark
The silky shark (''Carcharhinus falciformis''), also known by numerous names such as blackspot shark, gray whaler shark, olive shark, ridgeback shark, sickle shark, sickle-shaped shark and sickle silk shark, is a species of requiem shark, in the family Carcharhinidae, named for the smooth texture of its skin. It is one of the most abundant sharks in the pelagic zone, and can be found around the world in tropical waters. Highly mobile and migratory, this shark is most often found over the edge of the continental shelf down to . The silky shark has a slender, streamlined body and typically grows to a length of . It can be distinguished from other large requiem sharks by its relatively small first dorsal fin with a curving rear margin, its tiny second dorsal fin with a long free rear tip, and its long, sickle-shaped pectoral fins. It is a deep, metallic bronze-gray above and white below. With prey often scarce in its oceanic environment, the silky shark is a swift, inquisitive, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galápagos Shark
The Galapagos shark (''Carcharhinus galapagensis'') is a species of requiem shark, in the family Carcharhinidae, found worldwide. It favors clear reef environments around oceanic islands, where it is often the most abundant shark species. A large species that often reaches , the Galapagos reef shark has a typical fusiform "reef shark" shape and is very difficult to distinguish from the dusky shark (''C. obscurus'') and the grey reef shark (''C. amblyrhynchos''). An identifying character of this species is its tall first dorsal fin, which has a slightly rounded tip and originates over the rear tips of the pectoral fins. The Galapagos shark is an active predator often encountered in large groups. It feeds mainly on bottom-dwelling bony fishes and cephalopods; larger individuals have a much more varied diet, consuming other sharks, marine iguanas, sea lions, and even garbage. As in other requiem sharks, reproduction is viviparous, with females bearing litters of 4–16 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hammerhead Shark
The hammerhead sharks are a group of sharks that form the family Sphyrnidae, so named for the unusual and distinctive structure of their heads, which are flattened and laterally extended into a "hammer" shape called a cephalofoil. Most hammerhead species are placed in the genus ''Sphyrna'', while the winghead shark is placed in its own genus, ''Eusphyra''. Many different, but not necessarily mutually exclusive, functions have been postulated for the cephalofoil, including sensory reception, manoeuvering, and prey manipulation. The cephalofoil gives the shark superior binocular vision and depth perception. Hammerheads are found worldwide in warmer waters along coastlines and continental shelves. Unlike most sharks, some hammerhead species usually swim in Shoaling and schooling, schools during the day, becoming solitary hunters at night. Description The known species range from in length and weigh from . One specimen caught off the Florida coast in 1906 weighed over . They are u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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