這是《動物王國大探險展》史前生命區的暴龍導覽。在此聆聽這位陸地霸主的科學思辨。
上方可播放導覽語音。逐字稿與語音內容相同。
This is the T. rex stop in the prehistoric gallery of the Animal Kingdom Grand Adventure Exhibition. Listen here to the science of this overlord of the land.
Play the narration above. The transcript matches the audio.
眼前的恐龍正張著大口、甩動牠的脖子，牠來自巨木參天的白堊紀晚期，牠就是史前陸地的霸主：暴龍。
你今天有沒有吃雞蛋呢？那顆蛋，其實是暴龍的遠親。在現代生物分類學中，科學家已經有共識：「鳥類不只是恐龍的後代，鳥類本質上就是一種活著的恐龍」。
不同於現代鳥類發達的翅膀，暴龍的前肢比例極小。科學界多數認為，在演化過程中，暴龍家族走向了「極端特化」的路線，牠們把生存資源全部放到了巨大的頭部與咬合力上，而手臂可能因失去功能。手臂在天擇過程中逐漸縮小成現在看到的比例，這不僅能減輕身體前方的重量，更幫助牠們在移動時保持身體平衡。
電影中常看到暴龍狂奔的畫面，但是經過生物力學模擬顯示，由於巨大的身體限制，牠們平常步行的速度跟人類散步的速度差不多，即使全力衝刺也很難超過時速20公里。
眼前的暴龍，是遠古的頂級掠食者，更是一場跨越數千萬年的科學思辨。
The dinosaur before you opens a vast mouth and swings its neck. It comes from the late Cretaceous, when the great trees stood like pillars of the sky. It is the overlord of prehistoric land: the T. rex.
Have you eaten an egg today? That egg is, in fact, a distant relative of the T. rex. In modern biological classification, scientists already agree: birds are not only the descendants of dinosaurs; a bird is, in essence, a living dinosaur.
Unlike the developed wings of modern birds, the forelimbs of the T. rex are tiny in proportion. Most of the field holds that, in the course of evolution, the tyrannosaur family took a path of extreme specialization. They put all their resources of survival into the huge head and the force of the bite, and the arms may have lost their function. Under natural selection the arms shrank to the proportion we see, which not only lightened the front of the body but helped them keep balance as they moved.
Films often show a T. rex in a wild run, but biomechanical models show that, limited by that huge body, their ordinary walking speed was about that of a human stroll, and even a full sprint would struggle to pass twenty kilometers an hour.
The T. rex before you is a top predator of deep time, and more than that: a scientific argument spanning tens of millions of years.