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Golden moles are small, insectivorous burrowing mammals native to southern Africa. They form the family Chrysochloridae. They are taxonomically distinct from the true moles, which they resemble due to convergence. The golden moles bear a remarkable resemblance to the marsupial moles of Australia, so much so that, the marsupial/placental divide notwithstanding, arguments were once made that they were related, possibly because they are very primitive placentals and because of the many mole-like specializations. ==Characteristics== Golden moles live almost exclusively underground, beneath grassveld, forest, swamps, deserts, or mountainous terrain. Like several other burrowing mammals with similar habits, they have short legs with powerful digging claws, very dense fur that repels dirt and moisture, and toughened skin, particularly on the head. Their eyes are non-functional and covered with skin and fur, the ears are just tiny openings, and, like the marsupial moles, they have an enlarged leather-like pad to protect their nostrils. Their primary sense is that of touch, and they are particularly sensitive to vibrations that may indicate approaching danger. They range in size from about 8 to about 20 cm. They have muscular shoulders and an enlarged third claw on the forelimbs to aid digging, with no fifth digit and vestigial first and fourth digits; the hind feet retain all five toes and are webbed to allow efficient backward shoveling of the soil loosened with the front claws. They feed on small insects, which are located with the sense of hearing. Grant's golden mole (''Eremitalpa granti'') can cover 6 km each night looking for food.〔Piper, Ross (2007), ''Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals'', Greenwood Press.〕 While the desert species simply 'swim' through loose sand, all other species construct permanent burrows. The burrows are relatively complex in form, and may penetrate as far as a metre below ground. They include deep chambers for use as bolt-holes, and others as latrines. Excavated soil is pushed up to the surface as ridges or mole-hills, or is compacted into the tunnel walls. During extremely hot weather, Grant's golden mole will retreat to depths of around 50 cm and enter a state of torpor, thus conserving energy.〔 Females give birth to one to three hairless young in a grass-lined nest within the burrow system. Breeding occurs throughout the year. The adults are solitary, and their burrowing territory may be aggressively defended from intruders, especially where resources are relatively scarce.〔 Because these mammals were previously thought to have originated in Gondwana, golden moles used to be regarded as rather 'primitive' creatures: their low resting metabolic rate and their ability to switch off thermoregulation when inactive, however, are no longer regarded as indications that golden moles are undeveloped 'reptilian mammals', but rather as essential adaptations to a harsh climate. By going into a torpor when resting or during cold weather, they conserve energy and reduce their need for food. Similarly, they have developed particularly efficient kidneys and most species do not need to drink water at all. Like the tenrecs, they possess a cloaca, and males lack a scrotum. Golden moles use a head-dipping behavior to detect the vibrations produced by grass mounts in order to position themselves within detection range of the head-banging alarms produced by their termite prey. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Golden mole」の詳細全文を読む スポンサード リンク
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