全篇共分為 8 段，分別講述了北極熊對於研究人類的心臟病、糖尿病和骨質疏鬆等疾病的意義，以及它們不僅充滿智慧，而且富有情感的形象。

本篇考題英文原文與對應之中文翻譯整理如下。考生作答解題時若有對語意不清楚之處，請仔細查閱對照，以提升閱讀理解能力。

Why we need to protect polar bears 為何我們需要保護北極熊

1. 導論：北極熊特殊之處

   Polar bears are being increasingly threatened by the effects of climate change, but their disappearance could have far-reaching consequences. They are uniquely adapted to the extreme conditions of the Arctic Circle, where temperatures can reach -40°C. One reason for this is that they have up to 11 centimetres of fat underneath their skin. Humans with comparative levels of adipose tissue would be considered obese and would be likely to suffer from diabetes and heart disease. Yet the polar bear experiences no such consequences.

   北極熊正日益受到氣候變化效應的威脅，但它們的消失可能產生深遠的影響。它們獨一無二地適應了北極圈的極端條件，那裡的溫度可以達到零下 40 ℃。其中一個原因是，它們的皮膚下有厚達 11 厘米的脂肪。人類若擁有與此相當的脂肪組織會被認為是肥胖，並有可能患上糖尿病和心臟病。然而，北極熊卻沒有經歷這樣的結果。

2. 北極熊的特殊基因

   A 2014 study by Shi Ping Liu and colleagues sheds light on this mystery. They compared the genetic structure of polar bears with that of their closest relatives from a warmer climate, the brown bears. This allowed them to determine the genes that have allowed polar bears to survive in one of the toughest environments on Earth. Liu and his colleagues found the polar bears had a gene known as APoB, which reduces levels of low-density lipoproteins (LDLs) – a form of ‘bad’ cholesterol. In humans, mutations of this gene are associated with increased risk of heart disease. Polar bears may therefore be an important study model to understand heart disease in humans.

   劉世平及其同事在 2014 年的一項研究揭示了這個謎團。他們將北極熊的遺傳結構與它們來自溫暖氣候的近親棕熊的遺傳結構進行了比較。這使他們能夠確定使北極熊能夠在地球上最艱難的環境之一生存的基因。劉和他的同事發現北極熊有一個被稱為 APoB 的基因，它能降低低密度脂蛋白（LDLs）的含量，這是一種 “壞” 膽固醇。在人類身上，這種基因的突變與心臟病的風險增加有關。因此，北極熊可能是瞭解人類心臟疾病的一個重要研究模型。

3. 骨質密度特殊現象

   The genome of the polar bear may also provide the solution for another condition, one that particularly affects our older generation: osteoporosis. This is a disease where bones show reduced density, usually caused by insufficient exercise, reduced calcium intake or food starvation. Bone tissue is constantly being remodelled, meaning that bone is added or removed, depending on nutrient availability and the stress that the bone is under. Female polar bears, however, undergo extreme conditions during every pregnancy. Once autumn comes around, these females will dig maternity dens in the snow and will remain there throughout the winter, both before and after the birth of their cubs. This process results in about six months of fasting, where the female bears have to keep themselves and their cubs alive, depleting their own calcium and calorie reserves. Despite this, their bones remain strong and dense.

   北極熊的基因組也可能為另一種情況提供解決方案，這種情況特別影響到老年人口：骨質疏鬆症。這是一種骨骼顯示出密度降低的疾病，通常由運動不足、鈣攝入減少或食物缺乏所引起。骨骼組織不斷地被重塑，意味著骨骼被添加或移除，過程取決於營養物的供給和骨骼所承受的壓力。然而，雌性北極熊在每次懷孕期間都要經歷極端的條件。一旦秋天來臨，這些雌性北極熊就會在雪地裡挖產房，並在整個冬天都待在那裡，無論是在幼崽出生之前還是之後。這個過程導致了大約 6 個月的禁食，母熊必須保持自己和幼崽的生命，不斷消耗自己的鈣和熱量儲備。儘管如此，它們的骨骼仍然強壯而緻密。

4. 骨質密度解謎

   Physiologists Alanda Lennox and Allen Goodship found an explanation for this paradox in 2008. They discovered that pregnant bears were able to increase the density of their bones before they started to build their dens. In addition, six months later, when they finally emerged from the den with their cubs, there was no evidence of significant loss of bone density. Hibernating brown bears do not have this capacity and must therefore resort to major bone reformation in the following spring. If the mechanism of bone remodelling in polar bears can be understood, many bedridden humans, and even astronauts, could potentially benefit.

   生理學家 Alanda Lennox 和 Allen Goodship 在 2008 年為這個矛盾現象找到了解釋。他們發現，懷孕的熊在開始建造巢穴之前就能夠增加其骨骼的密度。此外，6 個月後，當它們終於帶著幼崽從巢穴中走出來時，沒有證據表明它們的骨骼密度明顯下降。冬眠的棕熊不具備這種能力，因此必須在第二年春天進行重大的骨骼改造。如果能夠理解北極熊的骨骼重塑機制，許多臥床的人類，甚至太空人都有可能受益。

5. 北極熊的智力

   The medical benefits of the polar bear for humanity certainly have their importance in our conservation efforts, but these should not be the only factors taken into consideration. We tend to want to protect animals we think are intelligent and possess emotions, such as elephants and primates. Bears, on the other hand, seem to be perceived as stupid and in many cases violent. And yet anecdotal evidence from the field challenges those assumptions, suggesting for example that polar bears have good problem-solving abilities. A male bear called GoGo in Tennoji Zoo, Osaka, has even been observed making use of a tool to manipulate his environment. The bear used a tree branch on multiple occasions to dislodge a piece of meat hung out of his reach. Problem-solving ability has also been witnessed in wild polar bears, although not as obviously as with GoGo. A calculated move by a male bear involved running and jumping onto barrels in an attempt to get to a photographer standing on a platform four metres high.

   北極熊對人類醫療的益處對我們的保護工作當然有其重要性，但這些不應該是唯一考慮的因素。我們傾向於想要保護我們認為是聰明的、擁有情感的動物，比如大象和靈長類動物。另一方面，熊似乎被認為是愚蠢的，在很多情況下是暴力的。然而，來自田野的傳聞證據卻對這些假設提出了挑戰，例如，證據指出北極熊具有良好的問題解決能力。在大阪天王寺動物園，一隻名叫 GoGo 的公熊甚至被觀察到利用工具來操縱它的環境。這隻熊多次使用樹枝來移開掛在它面前的一塊肉。在野生北極熊身上也看到了解決問題的能力，儘管不像 GoGo 那樣明顯。有一頭雄性北極熊經過深思熟慮後，經由助跑並跳上油桶，試圖接近站在四米高平台上的攝影師。

6. 北極熊的行為表現

   In other studies, such as one by Alison Ames in 2008, polar bears showed deliberate and focussed manipulation. For example, Ames observed bears putting objects in piles and then knocking them over in what appeared to be a game. The study demonstrates that bears are capable of agile and thought-out behaviours. These examples suggest bears have greater creativity and problem-solving abilities than previously thought.

   在其他，例如 Alison Ames 在2008年進行的研究中，北極熊表現出帶有目的和集中焦點的操縱行為。例如，Ames 觀察到北極熊把物體堆在一起，然後把它們打翻，似乎是在做遊戲。這項研究表明，熊有能力做出敏捷和深思熟慮的行為。這些例子表明，熊的創造力和解決問題的能力比人們以前想像的要強。

7. 北極熊的情緒表現

   As for emotions, while the evidence is once again anecdotal, many bears have been seen to hit out at ice and snow – seemingly out of frustration – when they have just missed out on a kill. Moreover, polar bears can form unusual relationships with other species, including playing with the dogs used to pull sleds in the Arctic. Remarkably, one hand-raised polar bear called Agee has formed a close relationship with her owner Mark Dumas to the point where they even swim together. This is even more astonishing since polar bears are known to actively hunt humans in the wild.

   至於在情緒上，雖然再次是傳聞證據，但人們看到許多熊在剛剛錯過獵物的時候，會擊打冰和雪，似乎是出於挫折感。此外，北極熊可以與其他物種形成不尋常的關係，包括與北極地區用於拉雪橇的狗玩耍。值得注意的是，一隻名為 Agee 的人工飼養的北極熊與它的主人 Mark Dumas 形成了一種親密的關係，以至於它們甚至一起游泳。這更令人吃驚，因為眾所周知，北極熊在野外會主動獵殺人類。

8. 結論

   If climate change were to lead to their extinction, this would mean not only the loss of potential breakthroughs in human medicine, but more importantly, the disappearance of an intelligent, majestic animal.

   如果氣候變化導致它們的滅絕，這不僅意味著失去了人類醫學上的可能突破，更重要的是，一種聰明、雄偉的動物的消失。