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What are they? -

What makes an island “recursive” is when it is contained within a lake that is situated on an island. Sometimes, this unique geological phenomenon can create multiple layers of islands within islands, thus forming a "recursive" structure.

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How they are created - Simply put, recursive islands can be formed through various geological processes such as volcanic activity, tectonic movements, and even simple erosion. Over time, lakes can grow on islands, and within these lakes new islands can appear, often through sediment deposition and changing water levels.

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Glover’s Reef, Belize -

While dozens of examples of recursion exist around the world, some are definitely worth mentioning here above others. One such place is Glover’s Reef. In the Caribbean, Glover’s Reef is a partially submerged atoll with an interior lagoon that contains several small islands, creating a layered, recursive landform typical of coral reef ecosystems.

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Huron’s recursive islands -

Lake Huron (which is part of the Great Lakes in North America) contains several recursive islands. Notably, Manitoulin Island has many of its own lakes with islands, including Sucker Lake and Mindemoya Lake (pictured).

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Asia’s recursive wonders -

Asia, with its vast and varied geography, is home to numerous recursive islands, particularly in archipelagos like the Philippines and Indonesia (pictured), where volcanic activity frequently shapes new islands within lakes.

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Vulcan Point, Philippines -

One such Asiatic island is Vulcan Point, located within Taal Volcano's crater lake on Luzon Island. As such, the tiny island sits within a lake on a volcano island in Taal Lake, which is on the larger Filipino island of Luzon.

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Lake Toba, Indonesia -

The largest volcanic crater lake in the world, Lake Toba contains Tulas Island, all of which are located on the Indonesian island of Sumatra. This is one instance of the ways in which volcanic activity can create recursive islands around the world.

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Papua New Guinea -

The Asian archipelago complex of Papua New Guinea includes several islands with inland water bodies and secondary islands. Much of these formations were created by the Pacific Ring of Fire, a band of volcanoes that stretch along the outskirts of the Pacific Ocean due to moving tectonic plates.

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Japan’s nested islands -

Another nation that is victim to the Ring of Fire is Japan, which has a diverse geography that includes recursive islands, such as those within lakes on volcanic islands. Pictured here is Lake Biwa, overlooking Okishima Island. These structures often arise from volcanic eruptions and the formation of calderas.

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Canadian islands -

Although Canada is famous for its islands and lakes to the north, the country is home to one unique instance of a recursive island. Located in the Kitikmeot Region at 69.79°E and 108.24°N is an island found in a lake and found on an island that has a lake located in the greater Victoria Island. Pictures of the area are extremely rare, and many of the islands and lakes do not have any official names.

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European examples -

Europe has its own share of recursive islands, such as those within Finland’s numerous lakes. Indeed, Finland has more than 187,000 lakes within its borders, and the islands located on a few of them often arise from glacial activity.

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Volcanoes and recursion - If you’re wondering exactly how these marvels of nature are created, then we have the answer! As mentioned already, many recursive islands result from volcanic activity, where calderas fill with water and new volcanic cones form islands within these calderas. But these are certainly not the only way that recursive islands are formed.

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Tectonic activity -

Tectonic plate movements can also contribute to the creation of recursive islands by lifting land up and creating inland water bodies, which subsequently develop their own islands through erosion and sedimentation.

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Artificial recursion -

Some recursive islands are even man-made, such as Dubai’s Palm Islands, which include artificial lagoons with islands. This feat of urban development was finished in 2007 and is truly a spectacular showcase of the human capability to mimic nature in astonishing ways.

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Lake Titicaca, Peru/Bolivia -

Another example of artificial recursion can be found in Lake Titicaca, the highest navigable lake in the world. Located on the border of Peru and Bolivia, the lake contains the artificially-constructed Uros floating islands. These islands even have smaller floating gardens, which creates nested landforms.

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Dynamic ecosystems -

Recursive islands often host truly unique ecosystems, with isolated flora and fauna that have evolved in distinct environmental conditions. This makes them hotspots for extensive biodiversity and ecological study.

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Scientific exploration -

Ongoing scientific exploration and research on recursive islands has the ability to contribute to our broader understanding of Earth’s geological history and the interconnectedness of natural phenomena.

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Historical significance -

Recursive islands often hold cultural and historical importance, with many serving as sacred sites, historical landmarks, or centers of ancient civilizations due to their unique and isolated nature.

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Tourism and recreation -

Many recursive islands are popular tourist destinations, offering unique landscapes and recreational opportunities, from hiking and boating to exploring volcanic craters and diverse ecosystems.

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Antarctic recursion - Even Antarctica’s icy landscape includes recursive features like subglacial lakes with floating ice shelves, where water pockets can create isolated ice islands. This simply illustrates how recursive formations can occur anywhere on Earth, even in the most hostile of environments.

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Dahala Khagrabari -

Aside from islands, there have also been countries and territories around the world that have been recursive. Located in Asia, the Dahala Khagrabari was once an Indian enclave within a Bangladeshi enclave, within an Indian enclave inside Bangladesh. But an exchange agreement in 2015 changed this and now the area, including the pictured palace, is under India’s jurisdiction.

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Nahwa -

The only surviving territory on the planet that is recursive is the Nahwa enclave, found in the Middle East. The enclave is part of the United Arab Emirates (UAE), but it lies within Madha, which belongs to the country of Oman. This region, in turn, is surrounded by the UAE.

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Historical records -

Ancient texts and maps often mention recursive islands as a reflection of their significance in navigation, mythology, and early scientific exploration. It is no small thing to say that recursive places have had a lasting impact on human history.

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Environmental preservation -

Preserving recursive islands is crucial for maintaining biodiversity, protecting unique ecosystems, and studying geological and ecological processes. Conservation efforts have never been higher to help these crucial places, but there are still many factors to consider.

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Climate change impact -

One such factor is climate change, which poses a threat to recursive islands due to rising sea levels and changing weather patterns. Shifts in the global climate can potentially alter or submerge these unique landforms, which means that entire ecosystems could be destroyed.

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Technological advances -

Modern technology, including satellite imagery, aids in the study and mapping of recursive islands, enhancing our understanding of their formation, structure, and ecological significance. Perhaps by analyzing these formations closely, we can learn how to protect them.

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Education and awareness -

Raising awareness about recursive islands and the overall environment can foster appreciation for natural wonders, promote environmental stewardship, and inspire interest in geology and ecology among the public and scholars.

Sources: (Geography Realm) (Britannica) (Curiocity) (NASA) (The Washington Post) (Smithsonian Institution) (Live Science)

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