嚙齒目 Rodentia

啮齿目（Rodentia）,源自拉丁文 rōdēns（"gnawer；啃咬者"）,意指这些动物中的大多数都有经常啃咬的习惯.囓齒動物,源自拉丁文 rōdēns（「gnawer；啃咬者」）,意指這些動物中的大多數都有經常啃咬的習慣.

Rodentia, from Latin rōdēns (“gnawer; one who gnaws”), in reference to the fact that the majority of these animals have the frequent habit to gnaw.

種的俗名種的俗名 Common names of members

家鼠、田鼠、松鼠、草原犬、豪猪、河狸、水豚、豚鼠和仓鼠.小鼠,

Mice, rats, squirrels, prairie dogs, porcupines, beavers, capybaras, guinea pigs, and hamsters.

分佈分佈 Distribution

除南极洲、新西兰和一些大洋岛屿外的所有大陆.除了南極洲、紐西蘭和一些海洋島嶼之外的所有大陸.

All continents except Antarctica, New Zealand, and some oceanic islands.

體型體型 Size

牠们中的大多数重量不到 100 克,而最大的种类可重达 66 千克.

牠們大多數的重量不到 100 克,而最大的品種可以重達 66 公斤.

The majority of them weigh less than 100 g, while the largest species can weigh up to 66 kg.

形態描述形態描述 Morphology

牠们大多是小型动物,身体扁平,四肢较短,尾巴较长.后肢通常有三到五个指头,而前肢通常有五个指头,包括一个可对折的拇指.不同的动物有许多移动方式,如四足行走、奔跑、穴居、攀爬、两足跳跃、游泳,甚至滑翔.由于肘部的存在,前臂相当灵活.牠们的门牙不断生长,牙根开阔,锋利无比.由于没有犬齿或前前臼齿,大多数动物都有多达 22 颗牙齿.在大多数物种中,门齿和颊齿之间有一个缺口,或称间隙.

牠們大多是身體扁平、四肢短小、尾巴長的小型動物.後肢通常有三到五個指頭,而前肢通常有五個指頭,包括一個對生的拇指.不同的動物會使用許多技巧來移動,例如四足行走、奔跑、穴居、攀爬、兩足跳躍、游泳,甚至滑翔.由於肘部的關係,前臂相當靈活.牠們的門牙不斷生長,根部開放,而且十分鋒利.由於沒有犬齒或前前臼齒,大多數動物都有多達 22 顆牙齒.在大多數的種類中,門牙與頰牙之間有一間隙,或稱為齒間隙 (diastema).

Most of them are small animals with squat bodies, short limbs, and long tails. The hind limbs often contain three to five digits, whereas the fore limbs typically have five digits, including an opposable thumb. Many techniques are employed by different animals to move about, such as quadrupedal walking, running, burrowing, climbing, bipedal hopping, swimming, and even gliding. The forearms are quite flexible because of the elbow. Their incisors are constantly growing, have open roots, and are razor sharp. With no canines or anterior premolars, the majority of animals have up to 22 teeth. In most species, there is a gap, or diastema, between the incisors and the cheek teeth.

生態與棲息地 Habitat & Ecology

从炙热的沙漠到寒冷的苔原,牠们几乎适应了所有类型的陆地环境.從烈日炎熱的沙漠到寒冷的苔原,牠們幾乎適應了所有類型的陸地環境.

From scorching deserts to frigid tundras, they have adapted to practically every type of terrestrial environment.

食性 Diet

尽管牠们通常是食草动物,吃树叶、草、种子、果实和根,但大多数微小物种也会伺机吃鱼、肉、蠕虫、昆虫和真菌.牠们中的少数已经进化到只以動物為食.

儘管牠們通常是草食性動物,以葉子、草、種子、果實和根為食,但大多數的微小物種都會伺機吃魚、肉、蠕蟲、昆蟲和真菌.其中有少數已進化到只以動物為食.

Despite being generally herbivores, eating leaves, grasses, seeds, fruits and roots, the majority of tiny species opportunistically consume fish, meat, worms, insects, and fungi. A limited number of them have evolved to only consume animal products.

繁殖 Reproduction

牠们中的许多都过着群居生活.群体大小因物种而异.牠们中的大多数繁殖率很高.牠们的产仔数多,一年能生多次.牠们的發育期很短.

許多類有群居習性,群體大小因種類而異.大多數的繁殖率都很高.牠們的產仔量大,一年可繁殖多次.幼體到成熟的用時很短.

Many of them live in groups. Group size varies among species. Most of them have a high reproductive rate. They have a large litter size and can give birth multiple times a year. Their maturation time is short.