Juno

每年的10月20日是一個(gè)有趣的日子——國(guó)際樹(shù)懶日。樹(shù)懶是樹(shù)棲動(dòng)物，它們動(dòng)作遲緩，常用爪倒掛在樹(shù)枝上數(shù)小時(shí)不移動(dòng)。樹(shù)懶的移動(dòng)速度是甫乳動(dòng)物中最慢的，比我們所知的烏龜還要慢，它們甚至懶得去吃，懶得去玩耍……但我們不要懶得去了解這種可愛(ài)的動(dòng)物哦！

Sloths are tree-dwelling mammals that mainly live in the rainforests of South andCentral America. With their long arms and 1）shaggy fur， they 2）resemble monkeys， butthey are actually related to armadillos and anteaters. They can be 0.6 to 0.8 meterslong and， depending on species， weigh from 3.6 to 7.7 kilograms.

With long， curved claws， sloths can hang upside down with little or no effort.Sloths spend most of their lives in the trees， where they hang upside-down frombranches and 3）vines. Sloths eat， sleep. mate and even give birth while hangingaround in the trees！

Sloths eat leaves， fruit and some select fresh green 4）shoots. Though mostlyherbivorous， they may occasionally snack on a 5）arval insect. They 6）lap dew dropsoff of leaves and fruits， and get additional water from their food. Sloths have the lowest7）metabolic rate of any mammal， which means that it takes them a long time to digestanything. So long， in fact， that a sloth usually only climbsdown from its tree about once a week to poop！

True to their name， sloths sleep for about 15 hours a day. They're mostly8）nocturnal， sleeping during the daytime and waking up at night to eat. Sloths moveextremely slowly， only managing to cover about 6–8 feet （1.8–2.4 meters） per minute.As a comparison， walking at your normal speed you'd probably be moving at about 84meters per minute. So even when walking you're about 39 times faster than a sloth！But sloths are surprisingly good swimmers. They can swim through water three timesfaster than they can move on the ground！

樹(shù)懶主要分布在南美洲和中美洲的熱帶雨林中，是一種樹(shù)棲哺乳動(dòng)物。樹(shù)懶有著長(zhǎng)長(zhǎng)的手臂和蓬松的毛發(fā)，很像猴子，但實(shí)際上它們與犰狳和食蟻獸有近親關(guān)系。它們可以長(zhǎng)到0.6～0.8米，根據(jù)亞種的不同，重量可達(dá)3.6～7.7千克。

由于樹(shù)懶長(zhǎng)而彎曲的爪子，它可以毫不費(fèi)力地倒掛在樹(shù)上。樹(shù)懶一生的大部分時(shí)間都在樹(shù)上度過(guò)，它們?cè)跇?shù)枝和藤蔓上倒掛著。樹(shù)懶在進(jìn)行吃、睡、交配等活動(dòng)時(shí)都懸掛在樹(shù)上，甚至連生產(chǎn)時(shí)也是掛在樹(shù)上！

樹(shù)懶吃樹(shù)葉、水果和一些精選的新鮮嫩芽。雖然它們大多是草食性的動(dòng)物，但偶爾也會(huì)吃一些幼蟲(chóng)昆蟲(chóng)。它們舔食樹(shù)葉和水果上的露珠，并從食物中獲得額外的水分。樹(shù)懶的新陳代謝率是哺乳動(dòng)物中最低的，這意味著它們需要很長(zhǎng)時(shí)間來(lái)消化任何東西。消化時(shí)間太長(zhǎng)了，事實(shí)上，樹(shù)懶通常每周只從樹(shù)上爬下來(lái)一次拉便便！

樹(shù)懶的懶惰名副其實(shí)，每天睡15個(gè)小時(shí)左右。它們大多在夜間活動(dòng)，白天睡覺(jué)，晚上醒來(lái)吃飯。樹(shù)懶移動(dòng)極慢，每分鐘只能爬6～8英尺（1.8～2.4米）。你可以比較一下，以你的正常速度行走，大約為每分鐘84米的速度。所以，即使走路，你也比樹(shù)懶快39倍！但出人意料的是，樹(shù)懶擅長(zhǎng)游泳。它們?cè)谒杏斡镜乃俣仁窃诘孛嫔弦苿?dòng)速度的三倍！