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Dwarf elephants are pre-historic members of the order Proboscidea , that, through the process of Allopatric Speciation , evolved to a fraction of the size of their modern relatives. Island Dwarfing is a biological phenomenon by which the size of animals isolated on an island shrinks dramatically over generations. Skeletal Remains of dwarf elephants have been found on the Mediterranean islands Cyprus , Malta (at Ghar Dalam ), Crete , Sicily , Sardinia , the Cyclades Islands and the Dodecanese Islands . Other islands where dwarf elephants were found are Sulawesi , Flores , Timor and other islands of the Lesser Sundas , the Channel Islands Of California , and Wrangel Island off Siberia . MEDITERRANEAN ISLANDS Dwarf elephants were once part of the Pleistocene fauna of several Mediterranean islands. Mediterranean dwarf elephants have generally been considered as Paleoloxodontine , derived from the continental Straight-tusked Elephant, ''Elephas (Palaeoloxodon) antiquus'' Falconer & Cautley, 1847. An exception is the dwarf Sardinian Mammoth , ''Mammuthus lamarmorae'' (Major, 1883), the only endemic elephant of the Mediterranean islands belonging to the mammoth line. During low sea levels, the Mediterranean islands were colonised again and again, giving rise, sometimes on the same island, to several species (or subspecies) of different body sizes. These endemic dwarf elephants were taxonomically different in each island or group of very close islands, like the Cyclades archipelagos. There is still much uncertainty about the time of colonisation, the phylogenetic relationships, and the taxonomic status of dwarf elephants on the Mediterranean islands. Sardinia
Sicily & Malta
Crete
Cyprus
The Cyprus Dwarf Elephant survived at least until 11.000 BP . Cyclades Islands Remains of paleoloxodontine elephants have been reported from the islands of Delos , Naxos , Kythnos , Serifos and Milos . The Delos elephant is of similar size to a small ''Elephas antiquus'', while the Naxos elephant is of similar size to ''Elephas melitensis''. The remains from Kythnos, Serifos and Milos have not been described. Dodecanese Islands On Rhodes islands, bones of an endemic dwarf elephant have been discovered. This elephant was similar in size to ''Elephas mnaidriensis''. Tilos island has had also at least one independent endemic elephant species. Two groups of remains of dwarf elephants have been found on Tilos island. They are similar in size to ''Elephas mnaidriensis'' and the smaller ''Elephas falconeri'', but according to Theodorou (1983, 1988) the two groups indicate sexual dimorphism. The remains had originally been designated to ''Palaeoloxodon antiquus falconeri'' (Busk, 1867). However, this name refers to the dwarf elephants from the island of Malta. As a result, since no migration route between the two islands can be proved, this name should not be used when referring to the elephant remnants from Tilos. Theodorou (1983) has accepted the temporal use of this name, until further material can be examined. The Tilos Dwarf Elephant was the first dwarf elephant of which its DNA sequence was known. The research was consistent with previous morphological reports according to which Palaeoloxodon is more closely related to ''Elephas'' than to ''Loxodonta'' or ''Mammuthus''. The Tilos Dwarf Elephant was the latest paleoloxodontine to survive in Europe . They became extinct just less than 4000 years BP . So this elephant survived well into the Holocene . CHANNEL ISLANDS OF CALIFORNIA The Columbian Mammoth (''Mammuthus columbii'') produced at the end of the Pleistocene separate, isolated population. One of these isolate groups was formed on the Californian Channel Islands, most likely about 40.000 years ago (although the time of isolation is not fully known). Selective forces on the Channel Islands resulted in smaller animals, what resulted into a new species '' Mammuthus Exilis ''. Channel Islands Mammoth ranged from 150-180 cm shoulder height. WRANGEL ISLAND During the last ice age, Woolly Mammoths (''Mammuthus primigenius'') lived on Wrangel Island in the Arctic Ocean . It has been shown that mammoths survived on Wrangel Island until 1700 B.C. which is the most recent survival of any known mammoth population. Wrangel Island is thought to have become separated from the mainland by 12.000 years BP . Survival of a mammoth population may be explained by local topography and climatic features, which permitted relictual preservation of communities of steppe plants. But due to limited food supply, they were much smaller than the typical Woolly Mammoth. Holocene mammoths from Wrangel Island ranged from 180-230 cm shoulder height. INDONESIA On Sulawesi and Flores evidence of a succession of distinct endemic island faunas has been found, including dwarfed elephants, dating until the Middle Pleistocene . Around the early Middle Pleistocene these dwarfed elephants were replaced by new immigrants of larger to intermediate sizes. Flores The present understanding of the succession of Stegodon species on Flores is that endemic dwarfs, represented by the Early Pleistocene species ''Stegodon sondaarii'' became extinct around 840.000 years ago. These dwarf forms were then replaced by the medium to large-sized ''Stegodon florensis'', a species closely related to the ''Stegodon trigonocephalus'' group found in Java and Wallacea islands. Sulawesi The dwarfed ''Stegodon sompoensis'' lived during the Pleistocene on the island of Sulawesi . They had a shoulder height of only 1,5m. REFERENCES
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