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83-603: Pearson Island is an island located in the Australian state of South Australia within the Pearson Isles an island group located in the larger group known as the Investigator Group about 63 kilometres (39 miles) southwest by west of Cape Finniss on the west coast of Eyre Peninsula . The group was discovered and named by Matthew Flinders on 13 February 1802. The island group has enjoyed protected area status since

166-578: A continent by plate tectonics , and oceanic islands, which have never been part of a continent. Oceanic islands can be formed from volcanic activity, grow into atolls from coral reefs , and form from sediment along shorelines, creating barrier islands . River islands can also form from sediment and debris in rivers. Artificial islands are those made by humans, including small rocky outcroppings built out of lagoons and large-scale land reclamation projects used for development. Islands are host to diverse plant and animal life. Oceanic islands have

249-449: A woodland of sheoak where both shelter and soil is present. The woodland’s density increases with altitude with the result that individual sheoaks will reach a height of 3 metres (9.8 feet) and support an understorey of species such as dryland tea tree , ruby saltbush and rock fern . Secondly, below the altitude of 100 metres (330 feet), two Melaleuca species, dryland tea tree and swamp paperbark , are present as thickets with

332-451: A "commuting" distance to an island that has enough resources to be sustainable. The presence of an island is marked by seabirds , differences in cloud and weather patterns, as well as changes in the direction of waves. It is also possible for human populations to have gone extinct on islands, evidenced by explorers finding islands that show evidence of habitation but no life. Not all islands were or are inhabited by maritime cultures. In

415-509: A "rafting event". This phenomenon is known as oceanic dispersal . Tropical storms have the capacity to transport species over great distances. Animals like tortoises can live for weeks without food or water, and are able to survive floating on debris in the sea. One case study showed that in 1995, fifteen iguanas survived a 300 km journey to Anguilla in the Caribbean , an island which no iguana had lived on previously. They survived floating on

498-426: A detailed review of 1,288 islands found that they were home to 1,189 highly-threatened vertebrate species, which was 41 percent of the global figure. Coral bleaching is expected to occur with more frequency, threatening marine ecosystems, some of which island economies are dependent on. Some islands that are low-lying may cease to exist given high enough amounts of sea level rise. Tuvalu received media attention for

581-622: A drainage system which drains into a creek which are respectively known as “North Creek” and “Main Creek”. Pearson Island was formed along with the rest of the Pearson Isles about 10,500 years ago following the rise of sea levels at the start of the Holocene . Geologically, Pearson Island and the other members of the Pearson Isles are the summits of an inselberg partially concealed by sea level rise . Pearson Island exhibits landforms caused firstly by

664-609: A few meters high, and are usually temporary. Changes in the flow speed, water level, and sediment content of the river may effect the rate of fluvial island formation and depletion. Permanent river islands also exist, the largest of which (that is completely inland) is Bananal Island in the Tocantins of Brazil, which has a maximum width of 55 kilometers. Lakes form for a variety of reasons, including glaciers , plate tectonics, and volcanism. Lake islands can form as part of these processes. The field of insular biogeography studies

747-470: A former Professor of Dentistry at the University of Adelaide. The 1969 expedition was a joint project conducted in conjunction with the then Department of Fisheries and Fauna Conservation and was led by scientists Scoresby Shepherd and I.M. Thomas. The most recent expedition discussed in the literature is an expedition organised by the then Department of Environment and Heritage in 2006 to visit islands within

830-402: A higher carrying capacity also have more genetic diversity , which promotes speciation . Oceanic islands, ones that have never been connected to shore, are only populated by life that can cross the sea. This means that any animals present on the island had to have flown there, in the case of birds or bats , were carried by such animals, or were carried in a sea current in what is known as

913-472: A loss of almost all the infrastructure in Dominica. Sea level rise and other climate changes can reduce freshwater reserves, resulting in droughts . These risks are expected to decrease the habitability of islands, especially small ones. Beyond risks to human life, plant and animal life are threatened. It has been estimated that almost 50 percent of land species threatened by extinction live on islands. In 2017,

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996-403: A mass of uprooted trees from a storm. Plant species are thought to be able to travel great distances of ocean. New Zealand and Australia share 200 native plant species, despite being separated by 1500 km. Continental islands, islands that were at one point connected to a continent, are expected to share a common history of plant and animal life up until the point that the island broke away from

1079-832: A minimum. Some islands became host to humans due to a land bridge or a continental island splitting from the mainland. Today, up to 10% of the world's population lives on islands. Islands are popular targets for tourism due to their perceived natural beauty, isolation, and unique cultures. Islands became the target of colonization by Europeans, resulting in the majority of islands in the Pacific being put under European control. Decolonization has resulted in some but not all island nations becoming self-governing , with lasting effects related to industrialisation , invasive species , nuclear weapons testing , and tourism . Islands and island countries are threatened by climate change . Sea level rise threatens to submerge nations such as Maldives ,

1162-743: A minority. Cultural attitudes related to communal ownership of land as well as a lack of individualistic decision-making may make some island cultures less compatible with the global capitalist economy, causing these nations to experience less economic growth. Islands have long been a popular target for tourism , thanks to their unique climates, cultures, and natural beauty. However, islands may suffer from poor transportation connectivity from airplanes and boats and strains on infrastructure from tourist activity. Islands in colder climates often rely on seasonal tourists seeking to enjoy nature or local cultures, and may only be one aspect of an island's economy. In contrast, tourism on tropical islands can often make up

1245-412: A new species in 1922. It was subsequently re-described as a sub-species of the black-footed rock-wallaby. The rock-wallabies originally occupied the “north section” of the island until 1960 when six specimens were accidentally released onto the “middle” and “south” sections of the island. By 1976, the six specimens had reproduced into a population estimated at 150 individuals compared with a population on

1328-599: A permanent caisson , a steel or concrete structure built in a closed loop and then filled with sand. Some modern islands have been constructed by pouring millions of tons of sand into the sea, such as with Pearl Island in Qatar or the Palm Islands in Dubai. These islands are usually created for real estate development , and are sold for private ownership or construction of housing. Offshore oil platforms have also been described as

1411-524: A phenomenon where new oceanic crust is formed, pushing away older crust. Islands sitting on the continental shelf may be called continental islands. Other islands, like those that make up New Zealand , are what remains of continents that shrank and sunk beneath the sea. It was estimated that Zealandia , the continent-like area of crust that New Zealand sits on, has had 93% of its original surface area submerged. Some islands are formed when coral reefs grow on volcanic islands that have submerged beneath

1494-423: A press conference publicizing the ongoing submerging of the island country. Tuvalu signed a cooperation agreement with Australia agreeing to annually allow 280 of its citizens to become permanent residents of Australia. The Marshall Islands, a country of 1,156 islands, have also been identified as a country that may be existentially threatened by rising seas. Increasing intensity of tropical storms also increases

1577-483: A priority target of conservation efforts, to prevent the extinction of these species. Despite high levels of endemism, the total species richness , the total number of unique species in a region, is lower on islands than on mainlands. The level of species richness on islands is proportional to the area of that island, a phenomenon known as the species-area relationship . This is because larger areas have more resources and thus can support more organisms. Populations with

1660-411: A restricted set of natural resources. However, these nations control some of the largest fisheries in the world, deposits of copper , gold , and nickel , as well as oil deposits . The natural beauty of island nations also makes them a magnet for tourism . Islands also have geopolitical value for naval bases , weapons testing , and general territorial control. One such example is French Polynesia ,

1743-468: A selection pressure for smaller animals that require less food. Having fewer predators would mean these animals did not need not be large to survive. Charles Darwin formulated the theory of natural selection through the study of island ecology. The species he observed on the Galápagos Islands , including tanager birds, contributed to his understanding of how evolution works. He first traveled to

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1826-509: A specific property known as adaptive radiation . In this process, a species that arrives on a group of islands rapidly becomes more diverse over time, splitting off into new species or subspecies. A species that reaches an island ecosystem may face little competition for resources, or may find that the resources that they found in their previous habitat are not available. These factors together result in individual evolutionary branches with different means of survival. The classical example of this

1909-414: A territory that receives substantial military expenditure and aid from France. Since the first discoveries of Polynesian, Micronesian , and other islands by Westerners, these nations have been the subject of colonization. Islands were the target of Christian missionaries . These missionaries faced resistance, but found success when some local chiefs used European support to centralize power. Beginning in

1992-514: A tree that is present in Australia, New Zealand, parts of South American, and New Guinea, places that today are geographically distant. A possible explanation for this phenomenon is that these landmasses were once all part of the continent Gondwana and separated by tectonic drift. However, there are competing theories that suggest this species may have reached faraway places by way of oceanic dispersal. Species that colonize island archipelagos exhibit

2075-603: A type of island. Some atolls have been covered in concrete to create artificial islands for military purposes, such as those created by China in the South China Sea . These atolls were previously low-tide elevations, landmasses that are only above water during low tide . The United Nations Convention on the Law of the Sea indicates that these islands may not have the same legal status as a naturally occurring island, and as such may not confer

2158-507: Is Darwin's finches , a group of up to fifteen tanager species that are endemic to the Galápagos Islands. These birds evolved different beaks in order to eat different kinds of food available on the islands. The large ground finch has a large bill used to crack seeds and eat fruit. The Genovesa cactus finch prefers cacti as a food source, and has a beak adapted for removing pulp and flowers from cacti. The green warbler-finch (in

2241-454: Is a feature called “Hill 781” with a height of 238 metres (781 feet) above sea level and which is located in the south west end of the North section and which is named after its height in the imperial unit of measurement . “Hill 781” and two other hills, “North Hill” and “East Hill” on the “north section” are of a height greater than 200 metres (660 feet) while the highest point on the remainder of

2324-588: Is actually a cognate of Swedish ö and German Aue , and more distantly related to Latin aqua (water). The spelling of the word was modified in the 15th century because of a false etymology caused by an association with the Old French loanword isle , which itself comes from the Latin word insula . Islands often are found in archipelagos or island chains, which are collections of islands. These chains are thought to form from volcanic hotspots , areas of

2407-497: Is the apple snail , initially introduced to the U.S. by aquarium owners. It has since been transported by hurricanes across the Gulf Coast and neighboring islands. These species compete for resources with native animals, and some may grow so densely that they displace other forms of existing life. For hundreds of years, islands have been created through land reclamation . One of the first recorded instances of this when people of

2490-628: Is the giant tortoise of the Seychelles , though it is unknown if it grew in size before or after reaching the island. Larger animals such as the hippopotamus tend to become smaller, such as in the case of the pygmy hippopotamus . This is known as insular dwarfism . In the case of smaller animals, it has been hypothesized that animals on islands may have fewer predators and competitors, resulting in selection pressure towards larger animals. Larger animals may exhaust food resources quickly due to their size, causing malnutrition in their young, resulting in

2573-481: Is widely used, it is not officially named. It also is referred to as the “North Island” within the context of the Pearson Isles by a number of sources. Pearson Island was briefly used for the grazing of sheep in the 19th century by Anton Schlink, who had leased nearby Flinders Island for the same purpose, however, with unsuccessful results due to the island’s “unfavourable, rocky and dry nature” and difficulties with stock management. The waters immediately adjoining

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2656-810: The Animals Protection Act 1912 , to protect the black-footed rock wallaby . The Pearson Isles were subsequently proclaimed as part of a fauna reserve declared under the Fauna Conservation Act 1964 either on 1 September 1966 or 16 March 1967. The island and other members of the group became part of the Investigator Group Conservation Park proclaimed under the National Parks and Wildlife Act 1972 in 1972 to "protect delicate island ecology and Australian sea lion and New Zealand fur seal haul-out areas”. On 25 August 2011, it and

2739-529: The Atlantic Ocean in search of an alternate route to the East Indies . These historians theorize that successful explorers were rewarded with recognition and wealth, leading others to attempt possibly dangerous expeditions to discover more islands, usually with poor results. About 10% of the world's population lives on islands. The study of the culture of islands is known as island studies . The interest in

2822-569: The Marshall Islands , and Tuvalu completely. Increases in the frequency and intensity of tropical cyclones can cause widespread destruction of infrastructure and animal habitats. Species that live exclusively on islands are some of those most threatened by extinction . An island is an area of land surrounded by water on all sides that is distinct from a continent. There is no standard of size that distinguishes islands and continents . Continents have an accepted geological definition – they are

2905-501: The Polynesians . Many of the previous island settlements required traveling distances of less than 100 km (62 mi), whereas Polynesians may have traveled 2,000–3,200 km (1,200–2,000 mi) to settle islands such as Tahiti . They would send navigators to sail the ocean without the aid of navigational instruments to discover new islands for settlement. Between 1100 and 800 BC, Polynesians sailed East from New Guinea and

2988-869: The Solomon Islands and reached the islands that make up the modern-day Fiji and Samoa . The furthest extent of this migration would be Easter Island in the East, and New Zealand in the South, with New Zealand's first settlements between 1250 and 1300. Historians have sought to understand why some remote islands have always been uninhabited, while others, especially in the Pacific Ocean , have long been populated by humans. Generally, larger islands are more likely to be able to sustain humans and thus are more likely to have been settled. Small islands that cannot sustain populations on their own can still be habitable if they are within

3071-493: The Solomon Islands created eighty such islands by piling coral and rock in the Lau Lagoon . One traditional way of constructing islands is with the use of a revetment . Sandbags or stones are dropped with a barge into the sea to bring the land level slightly out of the water. The island area is then filled with sand or gravel, followed by a construction of this revetment to hold it together. Islands have also been constructed with

3154-518: The South Australian Research and Development Institute (SARDI) in 2013. As of March 2014, the SARDI survey's results remain unpublished. Pearson Island is part of the island group which was first sighted by Matthew Flinders on Saturday, 13 February 1802 and subsequently named by Flinders on the same day as the Pearson Isles. The name of island derived from that of the group. While the name

3237-414: The lithosphere where the mantle is hotter than the surrounding area. These hotspots would give rise to volcanoes whose lava would form the rock the islands are made of. For some islands, the movement of tectonic plates above stationary hotspots would form islands in a linear chain, with the islands further away from the hotspot being progressively older and more eroded , before disappearing under

3320-450: The sea as a natural barrier to the introduction of new species, causing the species that do reach the island to evolve in isolation. Continental islands share animal and plant life with the continent they split from. Depending on how long ago the continental island formed, the life on that island may have diverged greatly from the mainland due to natural selection . Humans have lived on and traveled between islands for thousands of years at

3403-522: The 16th century, European states placed most of Oceania in under colonial administration . Pohnpei was colonized by Spain as early as 1526. It changed hands from Germany to Japan to the United States before joining the Federated States of Micronesia in 1982, maintaining a "free association" status with the U.S. Guam was a Spanish territory until 1898, and now is a unincorporated territory of

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3486-486: The 1960s and since 2011, it has been part of the Investigator Group Wilderness Protection Area . Pearson Island is notable both for its colony of Pearson Island Rock wallaby and for being a destination for scientific research. Pearson Island is located about 63 kilometres (39 miles) south west by west of Cape Finniss and about 25 kilometres (16 miles) south west of Flinders Island . It is

3569-506: The Hawaiian islands being home to irrigated fields of taro, whereas in some islands, like Tahiti, breadfruit was more widely cultivated and fermented in order to preserve it. There is archeological evidence that Canary Islanders would chew the roots of ferns for sustenance, a practice that wore heavily on their molars . These islanders would also grow barley and raised livestock such as goats . Many island nations have little land and

3652-501: The Investigator Group including Pearson Island and included a range of personnel from various government agencies including archaeologists, botanists, geologists and zoologists. A navigation aid has been located on the middle section of Pearson Island since 1968. It consists of a 2 m (6 ft 7 in) high tower with a group flashing light placed at a height of 79 m (259 ft) above sea level. The land on which

3735-666: The Origin of Species . The first evidence of humans colonizing islands probably occurred in the Paleolithic era, 100,000 to 200,000 years ago. Reaching the Indonesian islands of Flores and Timor would have required crossing distances of water of at least 29 km (18 mi). Some islands, such as Honshu , were probably connected to the mainland with a land bridge that allowed humans to colonize it before it became an island. The first people to colonize distant oceanic islands were

3818-481: The U.S. The decolonization era saw many island states achieve independence or some form of self-governance . Nuclear weapons testing on the Marshall Islands left many atolls destroyed or uninhabitable, causing the forced displacement of people from their home islands as well as increases in cancer rates due to radiation . Colonization has resulted in a decline of observance of traditional cultural practices in places such as Hawaii, where Native Hawaiians are now

3901-571: The absence of introduced pests. While first sighted in 1802 by Flinders, the island group was not visited by Robert Brown , the botanist accompanying Flinders, and the literature suggest that it was not visited by any of the scientists accompanying the Baudin expedition visited the island to make observations. Pearson Island was first visited by Edgar Waite , the then director of the South Australian Museum in 1914 followed by F Woods Jones ,

3984-414: The action of the sea has resulted in the erosion of the “lower inclined sheet structures” on the west side of the island at sea level resulting in the formation of a steep cliff face when compared to the relatively flat profile of the east side of the island. The eastern side of the island including the coastline of “Anchorage Cove” has layers of an aeolianite limestone up to 6–9 metres (20–30 feet) above

4067-570: The aid is located is owned by the Australian Maritime Safety Authority (AMSA) which is the Australian government agency responsible for navigation aids. Access to the island for the maintenance of the navigation aid is via helicopter . Pearson Island first received protected area status as part of the Pearson Isles on 27 July 1916 as part of a bird protection district declared under the Birds Protection Act 1900 and

4150-534: The body of the inselberg due to stresses within the overall granite body. The presence of orthogonal jointing within the sheet structures at right angles to the plane of the sheet structures create access for moisture into joints resulting in enlargement of the joints and the ultimate fracture of the sheet into “cubic, quadrangular or rhomboidal blocks” which can become either individual or field of free-standing granite boulders of 2–3 metres (6 feet 7 inches – 9 feet 10 inches) in height. Secondly,

4233-406: The continent. For example, the presence of freshwater fish on an island surrounded by ocean would indicate that it once was attached to a continent, since these fish cannot traverse the ocean on their own. Over the course of time, evolution and extinction changes the nature of animal life on a continental island, but only once it splits from the mainland. An example is that of the southern beech ,

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4316-451: The deposition of sediment by waves . These islands erode and grow as the wind and waves shift. Barrier islands have the effect of protecting coastal areas from severe weather because they absorb some of the energy of large waves before they can reach the shore. A fluvial island is an island that forms from the erosion and sedimentation of debris in rivers; almost all rivers have some form of fluvial islands. These islands may only be

4399-426: The distances and frequency with which invasive species may be transported to islands. Floodwaters from these storms may also wash plants further inland than they would travel on their own, introducing them to new habitats. Agriculture and trade also have introduced non-native life to islands. These processes result in an introduction of invasive species to ecosystems that are especially small and fragile. One example

4482-400: The ecological processes that take place on islands, with a focus on what factors effect the evolution , extinction , and richness of species. Scientists often study islands as an isolated model of how the process of natural selection takes place. Island ecology studies organisms on islands and their environment. It has yielded important insights for its parent field of ecology since

4565-512: The extent and thickness of deposits are taken into account, the Southern Hemisphere has the bulk of eolianite. Conditions favourable for formation of eolianite are: The most extensive deposits of eolianite in the world are located on the southern and western coasts of Australia . On the west coast, there are over 800 kilometres (500 mi) of eolianite cliffs, which are over 150 metres thick in some places. These cliffs, locally known as

4648-1067: The following mammals have been observed - Pearson Island rock-wallaby, bush rat and a breeding colony of Australian sea lion . The Australian sea lion, previously known as the "hair seal" has been seen on the island since the early 20th century. As of 2006, the following birds have been observed - Richard's pipit , wedge tailed eagle , white-faced heron , eastern reef egret , ruddy turnstone , masked woodswallow , galah , red-necked stint , Cape Barren geese , Horsfield's rufous tailed , Australian raven , white-fronted chat , crimson chat , rockhopper penguin , Nankeen kestrel , white bellied sea eagle , welcome swallow , silver gull , Pacific gull , singing honeyeater , budgerigah , rock parrot , golden whistler , osprey , house sparrow , red-capped robin , red-tailed tropicbird , great cormorant , white-browed scrubwren , crested tern , common starling , hooded dotterel , barn owl , masked plover , silver eye and breeding colonies of fairy tern , little penguin and sooty oystercatcher . As of 1996,

4731-423: The following reptiles have been observed - marbled gecko , four-toed earless skink , peninsula dragon and four-toed earless skink . Pearson Island rock-wallaby ( Petrogale lateralis pearsoni ) is a sub-species of the black-footed rock-wallaby which became isolated on what is now Pearson Island by sea level rise about 10,500 years ago. Specimens were first collected by F Woods Jones in 1920 and described as

4814-422: The formation of the inselberg and the characteristics of the granite from which it formed and secondly by the erosive and formative processes associated with the sea. Firstly, landforms associated with the formation of the inselberg and with its constituent material respectively are sheet structures and orthogonal jointing. Sheet structures which are flat or curvilinear layers of granite which have separated from

4897-460: The former species being reported as the “most widespread” of the two species. Thirdly, a scrub of swamp paperbark is present along the Main Creek watercourse in the eastern valley where favourable conditions such as “highly saline” soil and the shelter provided by the valley are present. Areas of the island close to its coastline have a heath cover. Fourthly, where the soil is granitic in origin,

4980-498: The habit of true warbler species) consumes spiders and insects that live on plants. Other examples of this phenomenon exist worldwide, including in Hawaii and Madagascar, and are not limited to island ecosystems. Species endemic to islands show a common evolutionary trajectory. Foster's rule (also known as the island rule), states that small mammals such as rodents evolve to become larger, known as island gigantism . One such example

5063-441: The heath is dominated by twiggy daisy-bush with sub-ordinate species such as common correa and shore westringia . Fifthly, grey saltbush dominates in the limestone-derived soils while marsh saltbush is present in both soil types. Sixthly, a herbfield featuring both karkalla and Austral stork's bill and fringed with round-leaved pigface is found on “the thinnest, most exposed soils on top of granite outcrops fronting

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5146-431: The island have been used for commercial fishing , recreational fishing and recreational diving . Pearson Island has been the subject of scientific interest since the early twentieth century in respect to its geology, its ecology and its terrestrial and marine flora and fauna. The island and its companions are an attractive destination for scientists because of their relative remoteness, the relative low human impact and

5229-467: The island is “South Hill” on the “south section” with a height of 115 metres (377 feet). The “north section” has two valleys - one opening onto a bay to the north known as “East Cove” while the other valley opens onto an unnamed cove on the east side of the island. Each is enclosed on one side by the ridge line on the west side of the island that connects “North Hill” and “Hill 781” and by a ridge line that connects “Hill 781” to “East Hill”. Each valley has

5312-454: The islands as a naturalist on HMS Beagle in 1835, as part of a five-year circumnavigation of Earth. He wrote that "the different islands to a considerable extent are inhabited by a different set of beings". Through the study of the finches and other animals he realized that organisms survive by changing to adapt to their habitat. It would be over twenty years before he published his theories in On

5395-643: The largest landmass of a particular tectonic plate . Islands can occur in any body of water, including lakes , rivers , seas . Low-tide elevations , areas of land that are not above the surface during a high tide , are generally not considered islands. Islands that have been bridged or otherwise joined to a mainland with land reclamation are sometimes considered "de-islanded", but not in every case. The word island derives from Middle English iland , from Old English igland (from ig or ieg , similarly meaning 'island' when used independently, and -land carrying its contemporary meaning. Old English ieg

5478-459: The largest of four islands that form the island group known as the Pearson Isles or the Pearson Islands. It consists of one land mass with two relatively smaller peaks rising out of the sea in an arc extending to the south east via a spit of rock connected to its most southerly point. The arc encloses a bay known as “Anchorage Cove” which is sheltered from the weather both from the west and

5561-404: The mainland, they had no need for boats. The motivation for island exploration has been the subject of research and debate. Some early historians previously argued that early island colonization was unintentional, perhaps by a raft being swept out to sea. Others compare the motivations of Polynesian and similar explorers with those of Christopher Columbus , the explorer who sailed westward over

5644-589: The majority of the local economy and built environment . These islands sometimes also require consistent foreign aid on top of tourism in order to ensure economic growth. This reliance can result in social inequality and environmental degradation . During tourism downturns, these economies struggle to make up the lost inflow of cash with other industries. Climate change threatens human development on islands due to sea level rise , more dangerous tropical cyclones , coral bleaching , and an increase in invasive species . For example, in 2017 Hurricane Maria caused

5727-408: The margins of the global carbonate belt, on the carbonate islands along northeastern Yucatan , and Rottnest Island . Eolianite occurs in many parts of the world. It occurs most extensively between the latitudes of 20° and 40° in both hemispheres, with little nearer the equator, and virtually no deposits nearer the poles. There is no apparent difference in distribution between the hemispheres, but if

5810-515: The past, some societies were found to have lost their seafaring ability over time, such as the case of the Canary Islands , which were occupied by an indigenous people since the island's first discovery in the first century until being conquered by the Spanish Empire in 1496. It has been hypothesized that since the inhabitants had little incentive for trade and had little to any contact with

5893-527: The population of the little penguin colony on Pearson Island was estimated to be 12,000 birds, making it the largest single colony in South Australia. As of 2011, the Pearson Island colony's status was unknown. In 2013, a tour operator based on Kangaroo Island visited the island and reported that the little penguins were "missing". A little penguin survey was scheduled to be conducted on Pearson Island by

5976-436: The present sea level which suggests that sea level was higher at some time in the past. The waters around Pearson Island fall to water depths greater than 50 metres (160 feet) within 500 metres (1,600 feet) from the island’s coastline. As of 1996, at least six plant associations are reported as being present on Pearson Island. Firstly, the parts of the island above the height of 100 metres (330 feet) above sea level support

6059-692: The rest of the Pearson Isles were excised from the Investigator Group Conservation Park to form the Investigator Group Wilderness Protection Area. Since 2012, the waters adjoining Pearson Island have been part of a sanctuary zone in the Investigator Marine Park . Island An island or isle is a piece of land, distinct from a continent, completely surrounded by water. There are continental islands, which were formed by being split from

6142-450: The same legal rights. Aeolianite Sayles coined the term in 1931, when he described the dune-shaped hills of Bermuda , consisting of bioclastic grainstones . Thus, Bermuda is considered the type locality for carbonate eolianite facies , with clearly defined cross-bedding , foresets, and topsets. Deposition is controlled by glacio-eustatic changes, with eolianites forming during interglaciations . Eolianites occur along

6225-775: The sea entirely. An example is the Hawaiian Islands , with the oldest island being 25 million years old, and the youngest, Hawaii , still being an active volcano . However, not all island chains are formed this way. Some may be formed all at once by fractures in the tectonic plates themselves, simultaneously creating multiple islands. One supporting piece of evidence is that of the Line Islands , which are all estimated to be 8 million years old, rather than being different ages. Other island chains form due to being separated from existing continents. The Japanese archipelago may have been separated from Eurasia due to seafloor spreading ,

6308-614: The sea”. Vertebrate animals observed on Pearson Island consist of mammals, birds and reptiles. An account from 1911 mentioned seals, Cape Barren geese, and a raptor's nest at the island's summit made from a ton of sticks. Some members of the visiting party hunted the Pearson Island rock wallaby, while another inspected the island's small lizards. An "abundance of seals" was noted, and some oystercatchers (then known as "redbills") were seen. Australasian snapper , Western blue groper and rock cod were caught in adjacent waters. Arthur Searcy recalled catching 30 and 40 lb groper there. As of 1996,

6391-424: The south and which can be respectively used as an anchorage and as a landing point. The three parts of the island are informally referred to in one source respectively as the “north section”, the “middle section” and the “south section”. An unnamed rock which is permanently dry is located immediately west of the "south section" of Pearson Island. The island has an area of 213 hectares (530 acres). Its highest point

6474-549: The study of islands is due to their unique cultures and natural environments that differ from mainland cultures. This is for a few reasons: First, the obvious political and geographic isolation from mainland cultures. Second, unique restraints on resources and ecology creating marine-focused cultures with a focus on fishing and sailing. Third, a lasting historical and political significance of islands. The Polynesian diet got most of its protein from fishing. Polynesians were known to fish close to shore, as well as in deep water. It

6557-450: The surface. When these coral islands encircle a central lagoon , the island is known as an atoll . The formation of reefs and islands related to those reefs is aided by the buildup of sediment in shallow patches of water. In some cases, tectonic movements lifting a reef out of the water by as little as 1 meter can cause sediment to accumulate and an island to form. Barrier islands are long, sandy bars that form along shorelines due to

6640-531: The then chair of anatomy at the University of Adelaide in 1920. The island was then the subject of three expeditions organised by the Royal Society of South Australia (RSSA) in the years 1923, 1960 and 1969. The 1923 expedition was funded by Sir George Murray , the then chief justice of Supreme Court of South Australia and led by F Woods Jones. The 1960 expedition was led by T. D. Campbell, anthropologist and

6723-438: The time of Charles Darwin . In biology, endemism is defined as the phenomenon where species or genus is only found in a certain geographical area. Islands isolate land organisms from others with water, and isolate aquatic organisms living on them with land. Island ecosystems have the highest rates of endemism globally. This means that islands contribute heavily to global biodiversity . Areas with high lives of biodiversity are

6806-853: The “north section” estimated between 250 and 300 in 1975. In 1974 and 1975 respectively, groups of rock-wallabies from the "north section" of Pearson Island were transferred to Thistle Island and Wedge Island in Spencer Gulf where the populations are reported in 2008 as being respectively 500 and 200 individuals. Previous experiments had been undertaken with the support of Captain P. Weir and Captain George Justice, who relocating pairs of wallabies to Liguanea , Price, Greenly and Four Hummocks islands. Little penguins were mentioned as being present on Pearson Island as early as 1914 and were described as "plentiful" in 1923. In 1933, J. T. Mortlock wrote that he saw "a good many" penguins on Pearson Island. In 2006,

6889-470: Was reported that Rapa Nui people were known to fish as far as 500 km (310 mi) from shore at coral reefs. Spear , line , and net fishing were all used, to catch tuna as well as sharks and stingrays . Island cultures also cultivate native and non-native crops. Polynesians grew the native yam , taro , breadfruit , banana , coconut and other fruits and vegetables. Different island climates made different resources more important, such as

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