大型蜥脚类恐龙研究  

Study on gigantic sauropoda dinosaurs

作　　者：钱迈平[1] 胡柏祥[2] 詹庚申[2] 邹松梅[2] 章其华[2] 

机构地区：[1]南京地质矿产研究所,江苏南京210016 [2]江苏省地质调查研究院,江苏南京210018

出　　处：《地质学刊》2010年第4期337-350,共14页Journal of Geology

基　　金：国家自然科学基金(40872006)

摘　　要：大型蜥脚类恐龙是地球历史上最大的陆地动物,其中已知体形最大者是梁龙,身长可达54m,所有已知身长超过20m的恐龙都属于蜥脚亚目。蜥脚类恐龙向大型化演化是为了占据更好的生态位空间,取得生存竞争的优势,其他演化都是围绕这一演化主线的配套演化。如:①小头长颈,是为了不用过多移动庞大的身躯就能在大范围内觅食。②大鼻孔,是为了增大呼吸吞吐量,供应庞大身躯的生命活动,由此可推想其心肺功能的强大,甚至可能除了一个主心脏外,还可能有多个小型辅助"心脏",以免单个心脏过于庞大。③长形的叶状牙齿,是为了快速连续地进食,力求每次都能撕扯下一大片鲜嫩的植物枝叶,不经咀嚼直接吞咽。④股骨比胫骨长,说明其虽不善于奔跑,但后肢支撑力很强,有时可站立起来吃高处的植物,或用前肢扑打敌害进行自卫。也说明其不是靠快速奔跑摆脱敌害,而是依仗庞大身躯及强大力量对抗敌害。⑤四足行走,是为了把庞大身体的重量分散到4个宽大的脚掌上,减小对地面的压强,提高通过松软地面的能力。由此可见,生物演化对其自身的生理和身体结构是牵一发而动全身的,演化的主线会带动一系列配套的演化,以求尽量达到对环境的最佳适应。Gigantic herbivorous sauropoda dinosaurs were very huge creatures. Diplodocus, among them, was up to 54 meters long and was the biggest terrestrial animal even. All of the dinosaurs, whose length was over 20 meters, were attached to sauropoda. Their main evolution was gigantism for having advantage of getting ecological niche, and other evolutions were cooperated with it. The characteristics of sauropoda dinosaurs, for example： ① Their long neck with a tiny head would have had the ability to browse at many levels and orientation needed not to move their gigantic body often. ② Their large nares would have allowed to breathe air in large throughput to support their gigantic body living, and so a sauropoda dinosaur would have had strong blood circulatory system, perhaps had a main heart and rudimentary auxiliary hearts＇ for fear a single heart too huge. ③ Their spatulate-shaped teeth would have had the ability to stripped longer portions of plant＇s stems in a single action, and ingested apace without mastication. ④ Their femurs were longer than their tibias, and showed they would have been ineffective runners but their thick legs were powerful, especially hind legs, and could stand up to graze on high plants, or to swat enemies. ⑤ They were quadrupeds with very wide and large paws, so a sauropoda dinosaur would have shared the weight of their titianic bodies by the four legs, and reduced pressure to ground for fear sinking. Thus it can be seen that：in live evolution, what happens to a small part may affect the whole. An organism＇s main evolution would have driven a series of cooperated evolutions in itself for adapt to the environment suitably as more as possible.

关 键 词：蜥脚类恐龙 大型化 中生代 

分 类 号：Q915.23[天文地球—古生物学与地层学]