Low Metabolism Lets Pandas Survive on Bamboo
VOA News
Last updated on: July 10, 2015 9:15 PM (source)
Low Metabolism Lets Pandas Survive on Bamboo
代謝率低讓貓熊得以吃竹子維 生
Reuters
July 10, 2015 9:15 PM
WASHINGTON—
Giant pandas eat vegetables even though their bodies are better equipped to eat meat. So how do these black-and-white bears from the remote, misty mountains of central China survive on a diet almost exclusively of a low-nutrient food like bamboo?
貓熊是吃菜的，雖然他們身體的配備是更適合吃肉的。這些中國 中部，偏遠多霧的山區裡的黑白色熊是如何單靠著(exclusively)竹 子這樣低營養價值(low- nutrient)的食物維生呢？
Scientists on Thursday provided an answer. They found that the giant panda is downright miserly in the amount of energy it expends on a daily basis - a level similar to that of the famously sluggish three-toed sloth - thanks to low levels of physical activity and low levels of thyroid hormones.
科學家於週四提出了答案，大貓熊對每一日消耗的能量是極為吝嗇的(downright miserly)，其程度大概等同與以懶散(sluggish)出 名的三趾樹懶，這都多虧了 (thanks to)其低度的身體運動還有甲狀腺賀爾蒙。
The critically endangered panda is the only one of the world's eight bear species with a vegetarian diet. Pandas, whose ancestors were carnivores, possess a digestive system that evolved to handle a meat diet even though bamboo now makes up about 99 percent of their food. Bamboo is tough to digest and the pandas must devour lots of it to survive.
貓熊是世界上八種以植物為主食的熊類之一，處於「極危」的瀕臨絕種 (critically endangered)狀態。貓熊的祖先是肉食性動物(carnivore)，消化系統(digestive system)經演化是可以處理肉食的，但竹子現在占了其99%的食物來源。粗糙的竹子不易消化，貓熊也必須吃(devour)大量的 竹子來維生。
(編按：物種瀕臨絕種的危急程度有數個分類，其中 “critically endangered” 是用來指「極危」，僅次於「絕滅」(extinct) 與「野外絕滅」(extinct in the wild)，可見 Wikipedia上的說明。)
The researchers studied three wild pandas at Foping Nature Reserve in Shaanxi province and five captive pandas at the Beijing Zoo. They found that the daily energy expenditure of these bears was only about 38 percent of other similar-sized animals.
研究人員在陝西省的佛坪自然保護區(Foping Nature Reserve)研究了三隻野生貓熊與五隻北京動物園圈養的(captive)貓 熊。研究發現，貓熊熱量的消耗 (expenditure)大概只有體積相似的動物的38%。
A key to the panda's remarkably low metabolism is the fact that it boasts extremely low levels of thyroid hormones, most likely due to a mutation in a gene called DUOX2 involved in thyroid hormone synthesis, the researchers said. The thyroid gland controls metabolic processes including energy use.
研究人員認為，貓熊代謝率低的關鍵在於擁有(boast)極低的 甲狀腺賀爾蒙，這可能是由於甲狀腺賀爾蒙合成有關的基因DUOX2發生了突變(mutation)。 甲狀腺這個腺體(gland)控 制代謝的過程，也包含能量的使用。
"Giant pandas achieved this low metabolism through a suite of morphological, behavioral, physiological and genetic adaptations during their long evolutionary history," said biologist Fuwen Wei of the Chinese Academy of Sciences' Institute of Zoology in Beijing, who led the study published in the journal Science.
此研究發表於「Science」期刊。北京的中國科學院動物 研究所(Chinese Academy of Sciences' Institute of Zoology)的動物學家與研究主持人魏輔文表示，「大貓熊漫長的演化史上，透過整套的(a suite of)型態上(morphological)、行為上、生理上、基因上的適應變化(adaptation)， 達成如此低的代謝率。」
The researchers said the size of the panda's brain, liver and kidney is relatively small compared to other bears.
與其它熊類相比(compared to . . .)，大貓熊的腦部、肝臟、腎臟也都相對較小。
"These reduced organ sizes likely contribute to their low energy demands," Wei said.
「這些器官縮小尺寸可能有助於(contribute to)讓 貓熊有較低的能量需求 (demand)。」
The researchers found that the wild pandas rested for more than half of any given day and traveled only about 65 feet (20 meters) per hour. With their low metabolism, the researchers said, the panda needs its coat of thick fur to retain body heat in order to keep warm.
研究人員發現，在觀察期間的任何一天，野生大貓熊有半天以上 在休息，每小時僅約移動 (travel) 65尺(20公尺)。據研究人員說法，因為代謝慢，大貓熊為了保暖所以需要那一層濃密的毛皮來留住(retain)體 熱。
There are only about 1,800 giant pandas left in the wild, according to the World Wildlife Fund, citing Chinese government figures.
根據世界自然基金會(World Wildlife Fund)引述中國官方的數據 (figure)，野生貓熊大約只有一千八百隻。
Language Notes
misty (a) 有霧的；霧氣覆蓋的
exclusively (ad) 專門地;專有地
downright (ad) 完全地，徹底地
miserly (a) 吝嗇的，小氣的 
make up (v phr) 組成；占…比例
carnivore (n) 肉食動物 
*herbivore (n) 草食動物 
devour (v) 狼吞虎嚥地吃，吃光
boast (v) 擁有；以有…自豪
mutation (n) 變種，突變
adaptation (n) (生物)適應性的變 *此字常見於指小說、電影等等的「改編」或「改編作品」
retain (v) 留住；擋住
figure (n) 數字 *這個字有多個語意，常見意思有「人影」、「體態」、「名人」；亦可作動詞，有片語figure out，意思是 「想出來」、「搞清楚」
Check your vocabulary!
Fill in the blanks with a word or phrase from the list above. Make necessary changes. After you finish, select the text above to reveal the hidden answers.
1. Can you read this figure? Is it a three or an eight?
2. He's working on a screen adaptation of his latest novel.
3. She's being downright difficult and obstructive.
4. The city boasts two excellent museums.
5. The office staff are almost exclusively female.
編譯：簡嘉呈
|
A one-year-old panda Fu Bao born to Yang Yang takes a nap at the top of a tree at the end of the visitors hours at Schoenbrunn Zoo in Vienna, Austria, Aug. 27, 2014. See more on VOA.
