Introduction
前言
The soil of China conceals many buried treasures, from mundane but valuable coal and iron ore to the relics of ancient dynasties. Near the city of Xi’an in what is now Shaanxi Province, a whole army of terra cotta warriors stands guard over the tomb of the first emperor of the Qin Dynasty, who united China more than two thousand years ago through diplomacy and war. Far to the south, archaeological sites in eastern Yunnan Province have offered up artefacts from the long-extinct kingdom of Dian, the most striking of which are bronze vessels whose lids are decorated with elaborate carved figurines arranged in scenes of hunting, combat and even human sacrifice. Excavations have recovered animal bones that were used to pose questions to spirits and ancestors by the rulers of the Shang Dynasty, the earliest Chinese dynasty whose existence is documented by firm historical and archaeological evidence. The questions were written on the “oracle bones” in symbols that are clearly precursors of the modern Chinese characters that people use every day to read newspapers, write text messages and surf the internet.
中国的大地蕴藏着无数宝藏，从常见但富含价值的煤矿和铁矿，到历代王朝传承下来的非凡遗迹，可谓应有尽有。在如今陕西省西安市附近，著名的陶土做成的兵马俑军队守卫着秦朝第一个帝王秦始皇的陵墓。这位帝王在两千多年前通过外交和战争统一了中国。而远在中国南部，云南省东部的考古遗址出土了早已消亡的古滇国文物，其中最令人震撼的是一尊青铜器，器皿的盖子上雕刻着精美的狩猎、战争甚至人牲的场面。商朝是中国最早的有可靠历史学和考古学证据的朝代。人们发掘出了商朝统治者用来向神灵和祖先问卜的动物骨骼——“甲骨”，上面书写的符号即“甲骨文”，正是中国人如今每天阅读报纸、书写文章和浏览网页时所使用的汉字的前身。
Fig1. A palaeontologist’s tent, pitched among Jurassic rock outcrops in the Xinjiang region of northwest China that yield spectacular fossils of dinosaurs and other vertebrates..
新疆侏罗纪恐龙化石点的科考队员帐篷
[Fig2. Terra cotta warriors standing eternal guard over their emperor.
守护皇陵的兵马俑
[Fig3. An inscribed bone fragment used in divination.
刻有甲骨文的甲骨
The beginning of the Shang Dynasty, representing the dawn of the part of Chinese history that can clearly be distinguished from legend, is separated from the present by more than three thousand years. That span of time is awe-inspiring, when seriously contemplated, but still an eyeblink compared to the duration of a far longer story that has also left its traces buried beneath the soil. In many parts of China are exposed rock strata that contain fossils millions or even hundreds of millions of years old, the petrified remains of dynasties of plants and animals that flourished long before the Shang and the Qin. Just as archaeologists can piece together much of the history of the Shang from the material evidence of oracle bones and bronze cauldrons, palaeontologists can use fossils to reconstruct the far longer and more outlandish history of life on Earth.
三千多年前建立的商朝是中国历史中现实与神话的分界线。当我们认真审视这段历史，会发现虽然其时间跨度漫长，但是相对于同样留下痕迹却深埋在土壤之下的另一个历史悠长的故事来讲，不过是一眨眼的功夫罢了。放眼中国各地，都有承载着距今百万甚至上亿年之久的化石的岩层，这些化石所记录的动植物王朝，远在商、秦之前就已经繁荣昌盛了。正如考古学家能够从发掘出的甲骨和青铜器中拼凑出商代的历史概貌，古生物学家也能够用化石信息重建更加遥远和奇异的地球生命史。
[Fig4. Exquisitely ornamented bronze ware from the Shang Dynasty, which ruled from about 1600 to 1046 BC.
商代（公元前1600-1046年）的精美青铜器
The subject of this book is one particular strand in the history of life, namely the story of our own group – the vertebrates – as documented in the Chinese fossil record. Through approximately the past half-billion years of geological time, an ever-changing menagerie of these backboned animals has inhabited the part of the Earth’s surface that is now China, leaving fossil remains at every turn. The tiny bodies of early jawless fishes emerge from hillsides in eastern Yunnan, geographically close to the bronze relics of the kingdom of Dian but separated from them by an immense gulf of time. In Liaoning Province, in the northeast, early birds and small predatory dinosaurs can be found within rock layers laid down in Cretaceous lakes, many still lying in mantles of preserved feathers. Caves and fissures near Beijing contain the bones and tools of ancient humans, alongside the remains of other animals. Each of these occurrences is like a glimpse into a different slice of the remote past, a different lost world entombed in stone.
本书的主题是关于地球生命史中特定的一段，即我们人类自己所属的类群——脊椎动物——在中国的化石所揭示的历史。在过去的大约五亿年间，各种各样的拥有脊椎骨的动物们栖息在中国的这片土地上，并在每个角落都留下了化石遗迹。人们在云南东部的山丘上发现了早期无颌鱼类细小的身体，虽然在地理位置上与古滇国青铜器的发掘点临近，但是两者却被时间的鸿沟赫然分开。在东北的辽宁省，远古的鸟类和小型肉食恐龙沉睡在白垩纪湖泊的岩层中，许多身上依然覆盖着羽毛。北京郊区的山洞和岩缝中则保存着原始人的骨骼和他们使用过的工具，以及其他动物的遗骸。这些发现好似打开了一扇扇窥视远古历史的天窗，让人们得以了解那些深埋在岩石中的“迷失的世界”。
Fig5. A fossil of the small dinosaur Microraptor gui from the Early Cretaceous of Liaoning, showing preserved feathers.
辽宁发现的白垩纪早期的恐龙——顾氏小盗龙，羽毛也被保存下来。
The glimpses provided by the fossil record are few and far between, and distinctly haphazard. Attempting to make sense of them is like trying to reconstruct an elaborate military parade from a collection of snapshots taken by an excitable chimpanzee that swivels its camera at random among the vehicles, marching soldiers and spectators, sometimes taking a dozen pictures in rapid succession and sometimes leaving the button untouched for ten or twenty minutes as troops and tanks sweep by unrecorded. Nevertheless, the efforts of many palaeontologists applied to the raw material of the Chinese fossil record have pieced together the general outlines of a parade in which the marchers are not military troops but rather dinosaurs, woolly mammoths, low-browed men and women with stone axes, and other representatives of vertebrate life through the long millennia of China’s geological past.
然而这些化石提供的记录稀少而分散，其发现也确属偶然。想要在其中找出意义，就好像试图通过一只拿着相机的黑猩猩所拍摄的照片来重构一场盛大的军事游行的全貌一样困难重重，因为这只激动的家伙会挥舞着相机对着周围的车辆、军人和观众时不时胡乱地连拍，而当坦克和军队列队驶过时却又十几分钟都不碰一下相机！然而众多古生物学家通过对中国化石材料地努力研究，成功拼接出了这场游行的大致轮廓：它的参与者不是军人，而是恐龙、猛犸象、挥舞着石斧的低额头的男女原始人，以及其他在漫长中国地质历史中的脊椎动物的代表。
Fig6. An enthusiastic but unreliable photographer.
热情但不靠谱的黑猩猩摄影师
Some of the marchers naturally slither, and others swim or fly. At first the only marchers are a few jawless fishes, which are soon crowded out almost entirely as fishes of other kinds and eventually land vertebrates take their places. Species are periodically lost to extinction as the march continues, but are replaced by others that are newly evolved or newly introduced to China from other regions. Now and then an episode of mass extinction thins the ranks dramatically, but in general new marchers are added at such a rate that the total number gradually swells. By the time the march of vertebrate life in China reaches the present, it contains a remarkable and motley collection of creatures – all of the vertebrates that inhabit China today, from fish in Bohai Bay to yaks in the Himalayas and Chinese people from every walk of life.
这些“游行者”有的爬行，有的游泳，还有的飞行。最早参与的游行者仅仅是几种无颌鱼类，不久之后就几乎被其他鱼类挤出了视野，最后陆生脊椎动物也加入进来抢占阵地。随着游行队伍的前进，生物物种在周期性地灭绝，但很快又被新演化出的物种和来自中国之外的外来物种所替代。时不时发生的大规模灭绝事件戏剧性地缩减了游行的队伍，但是总体来讲总会有新的游行者以某种频率加入进来，使队伍的规模始终在缓慢地增大。当脊椎动物的征途进行到了今天，在中国大地上已形成了形形色色的众多物种——现今栖息在中国的所有脊椎动物，从渤海湾的鱼类到喜马拉雅山上的牦牛，以及遍布中国大地的每一个中国人，都是其中的一员。
Fig7. The “Yellow River Elephant” (Stegodon) from the Pleistocene of Gansu Province.
甘肃发现的更新世的黄河象骨架（中国古动物馆）
The march of vertebrate life in China has not taken place in isolation, and in fact is an integral part of a larger march encompassing the planet as a whole. Throughout Earth’s history, groups that have evolved and begun to flourish in one area have often spread far and wide, becoming more numerous and varied in the process. At any given time in the geological past, the vertebrate fauna inhabiting what is now China would have been similar in many ways to its counterparts elsewhere, although with myriad differences of detail and some larger discrepancies. The distribution of vertebrates in our modern world exemplifies this balance between uniformity and heterogeneity. China resembles many other countries in having native bears and deer, herons and magpies, pit vipers and agamid lizards, and so on. But Canadian deer, for example, are different from Chinese deer, and there are significant groups of modern vertebrates – such as kangaroos, rhinoceroses and hummingbirds – that are not found in China at all. The march of vertebrate life is a global phenomenon, but one with important local variations.
中国脊椎动物的演化并不是独立发生的，它们其实是这个星球上更大规模的动物演化的一个缩影。纵观地球历史，一个生物类群进化并逐渐繁盛后，经常会从起源地向其他地区扩散，达到种类和数量的极致。回眸任何一个地质历史时期，生活在现今中国的脊椎动物群与同时期的其他地区的脊椎动物群虽有众多相似之处，也不乏具体乃至重大的差别。当今世界脊椎动物的分布，就显示了这种一致性与差别性的美妙平衡。比如，中国和其他许多国家一样，都拥有熊、鹿、鹭鸟、喜鹊、响尾蛇和飞蜥，但加拿大的鹿与中国的鹿就有所不同。很多其他脊椎动物，比如袋鼠、犀牛和蜂鸟在中国就不见踪影。脊椎动物的演化是个全球现象，但也包含了很多地方性的特色。
Fig.8 A bust of “Peking Man”, a form of the primitive human species Homo erectus.
属于直立人的原始古人类——北京人的复原头像（中国古动物馆）
China’s fossil record, like that of any country, is therefore unique. It contains the relics of a succession of floras and faunas that inhabited a particular part of the Earth’s surface in the remote past, perceived in a series of glimpses – the chimpanzee’s snapshots – whose clarity and timing are dictated by the vagaries of the local geology. Studying this record brings the march of vertebrate life into view through a specifically Chinese lens, providing information that augments and complements what can be learned from fossils that occur elsewhere in the world. Better yet, the past two or three decades have seen a surge in all types of palaeontological activity in China, from hunting for fossils in previously untapped places to publishing scientific papers about new discoveries, and to building palaeontological museums. As a result of the ongoing fossil rush, the story of the vertebrate life of China’s past is coming into sharper focus than ever before. The aim of this book is describe science’s current understanding of that story in a clear and accessible way, with proper attention to the global context, and to convey a hint of the wonder and fascination of standing face-to-face with the fossils themselves.
由此而言，中国的化石记录与其他地区一样都是独特的。它所记录的动植物群的遗迹，仅仅是地球远古时期的一个特定角落的一系列快照——就像前文的那个黑猩猩所为——其清晰度和时间点的选择由当地的地质特征所决定。尽管如此，从中国的特有镜头，我们能提供更多、更完整的信息，以了解世界脊椎动物的演化。更令人高兴的是，在过去的二三十年，中国经历了古生物学领域的发展高潮，从在少有触及的地方发掘化石，到出版各种学术文章和报道新的发现，再到建立古生物专题博物馆。在持续的化石发掘浪潮下，中国脊椎动物的历史故事正在变得前所未有地清晰。本书的目的就是要用清晰易懂的方式讲述目前科学界对这一故事的了解，并尽力将那些化石栩栩如生地带到读者面前，展现它们的神奇与魅力。