Shownotes Transcript
英语新闻|长颈鹿进化出长脖子是为了……找对象 Chinese researchers offered a new explanation for the evolutionary mystery of giraffes' long necks: They were elongated by head-bashing combat in competition for mates. 近日，一项中国科学家进行的研究揭开了长颈鹿进化出长脖子之谜，研究表明，长颈鹿长脖子形成是由雄性间的求偶竞争推动的。 The study published in the journal Science last Friday revealed that the tallest land animal on Earth used its two-to-three-meter swinging necks as a weapon in the male courtship competition. 6月3日发表在国际权威期刊《科学》上的这篇研究认为，早期的长颈鹿本来就身体比较高大，由于性选择的加持，发展出来了利用甩动脖子和头部攻击的方式与对手竞争，使得颈部迅速变长至2到3米。 In 1996, a team from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) under the Chinese Academy of Sciences discovered a 17-million-year-old fossil in the vast Gobi wilderness in northwest China's Xinjiang Uygur autonomous region. 1996年，中国科学院古脊椎动物与古人类研究所的考察队伍在新疆准噶尔盆地北部的茫茫戈壁之中，发现了一具距今1700万年的神秘化石。 The fossil features disk-shaped headgear equipped with a helmet-like horny cap, and particularly complex head and neck joints. 这是一件大型反刍动物的脑颅化石，其脑袋顶上长着一个巨大的圆盘，完全覆盖了头顶，就像一顶帽子。研究人员进一步观察发现，它的颈椎异常粗壮，具有非常复杂的头颈和颈间关节。 They analyzed the beast's inner ear structures, finding them distinct from the ox and the deer, and instead consistent with the extant giraffe. 研究发现，‘怪兽’的内耳与之前认为的最有可能的牛科截然不同，与鹿科、麝科等也不同，反而与现生的长颈鹿在关键特征上是一致的。 It is named "Discokeryx xiezhi" since its single ossicone recalls the xiezhi, a one-horned creature from ancient Chinese mythology. 由于这个神秘“怪兽”与中国古代神话中的独角神兽“獬豸”形象有些许联系，因而得名獬豸盘角鹿。 Wang Shiqi with IVPP and his colleague revealed in the new study that the strange beast's horns could serve as a cushion in the collision and the joints between the skull and cervical vertebrae could effectively protect the neck from breaking in the violent collisions. 王世骐介绍，此次研究的盘角鹿，它的每节颈椎都非常粗壮，并且具有哺乳动物中最复杂的头颈与颈椎之间的关节。这种结构特别适应于高速的头对头撞击。 It is similar to the East African Plateau about 7 million years ago when a forest environment degenerated into open grassland, prompting the giraffe ancestors to adapt to the new environment and become taller. 可以推测，这样的情况与东非高原的情况类似：约在700万年前，东非高原由森林环境转变为开阔的草原，远古长颈鹿赖以生存的环境逐渐消失，促使它们必须适应新的变化。 It is the courtship struggle that led to the rapid neck elongation over a period of 2 million years, and by dint of that advantage, giraffes occupied a relatively marginal, but rewarding ecological niche — feeding on high foliage out of reach of zebras and various antelopes, according to the study. 通过这种极端的斗争方式，在性选择的加持下，在200万年的时间内长颈鹿的颈部迅速加长，成为现生的长颈鹿属，从而有效占领了取食高处树叶这样一个相对边缘化、但回报颇丰的生态位。 combat 英[ˈkɒmbæt]；美[ˈkɑːmbæt] n.战斗，斗争 v.战斗；防止；减轻 extant 英[ekˈstænt]；美[ekˈstænt] adj.现存的，仍然存在的 elongation 英[ˌi:lɒŋ'ɡeɪʃn]；美[ˌilɒŋ'ɡeɪʃn] n.延长；延长线；<机>延伸率；<天>距（角）**