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The fossilized footprints of swimming footprints in lizards and dinosaurs are not romantic-zhongguorentiyishu

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Identification of swimming footprint fossils: the non romantic result of the remains of the lizard leaves a sickle shaped footprint – Zong Da, sina science and technology news on December 19th, no doubt dinosaurs have the same swimming ability as most modern large animals. But the evidence for dinosaur swimming has been controversial. In early studies, paleontologists discovered some unusual quadrupedal animal whereabouts, but these dinosaurs only in the foot or foot mark on sediments. Some scholars believe that the dinosaurs were swimming when they left footprints, and the water held up their bodies, while the front foot or hind foot left footprints in the pull. Is that really the case? Are lizards good swimmers? A new study in the northwest of Gansu province China Yanguoxia fossil footprints point, China University of Geosciences (Beijing) and from the UK, United States, Canada, Germany and other research institutions and scholars, Yanguoxia only after toe marks left by the dinosaur footprint is walking on the ground, instead of the traditional thought is the product of swimming. The results are published today in the open access journal Scientific Reports by Nature publishing group. Yanguoxia Yanguoxia fossil footprints formed in Early Cretaceous 120 million years ago, the Gansu Provincial Geological Museum chief engineer professor Li Daqing after excavation and survey of more than 2 years, currently in Yanguoxia area of about 2 square kilometers area, a total of more than 10 dinosaur footprints, thousands of fossil footprints. Professor Zhang Jianping, a renowned expert in the field of Geology and geology, holds that the size, quantity, diversity, and preservation of the footprint of salt pot gorge are not only unprecedented in China, but also in Asia at least. The dinosaur footprint includes the foot, foot, bird, ancient bird and pterosaur footprints. This provides abundant physical materials for dinosaur footprints, ancient ecology and paleoenvironment studies in China. It is also of great significance to the study of dinosaur distribution and palaeogeography in Northwest china. The relationship between sickle – footprint sickle shaped footprint and multi track track makers drawing Zhang Zongda and the world of similar footprint, sauropod dinosaur footprints Yanguoxia generally circular, the front has 4 or 5 clear zhaohen. They are fully consistent with the characteristics of the large, middle sized dinosaur, such as the dragon and so on, and the giant herbivorous dinosaur with a long neck. At the same level, however, the multi legged footprints are "abnormal". They look like a huge sickle, that is, only the toes of the hind legs are kept, no heel, and no forefoot footprint. "No one thought these giant dinosaurs could walk on their hind legs – they’d have to fall down." "The final study shows that they were indeed walking at the time, because these sickle like tracks are almost identical to the front of the footprint of the common lizards," said Xing Lida, Ph. D., a young scientist at the University of geology, who led the project. Some scholars, including even some of our research team, held that the dinosaurs were swimming, with their forelimbs floating in the water, and the hind legs"

蜥脚类恐龙游泳足迹化石鉴定:沉积不浪漫的结果 蜥脚类留下镰刀状足迹-绘图张宗达   新浪科技讯 12月19日消息 毫无疑问,恐龙也和大多数现代大型动物一样拥有游泳的能力。但有关恐龙游泳的证据却一直存在争议。在早期的研究中,古生物学家们发现过一些不同寻常的四足动物行迹,但这些恐龙只有前足或后足在沉积物上留下了印记。有学者据此认为这些恐龙留下足迹时正在游泳,水体托起了它们的身体,而前足或后足则在划水时留下了足迹。事实果真如此吗?   蜥脚类是优秀的泳者吗?   在一项针对中国西北部甘肃省盐锅峡足迹化石点的新研究中,中国地质大学(北京)和来自英国、美国、加拿大、德国等研究机构的学者发现,盐锅峡只有后足趾痕的足迹其实是由恐龙在地面行走中所留,而非传统认为的是游泳的产物。这个成果于今日发表在Nature出版集团旗下开放获取期刊《科学报告》(Scientific Reports)。 盐锅峡化石点   盐锅峡的足迹形成于1.2亿年前的早白垩世,甘肃省地质博物馆总工程师李大庆教授经过2年多的系统发掘和调查,目前在盐锅峡一带约2平方千米的区域内,共发现10余恐龙足迹化石点,数千个足迹化石。知名遗迹学家与地质公园专家,地质大学的张建平教授认为,盐锅峡足迹点规模之大、数量之多、多样化之高、保存之好,不仅在中国,至少在亚洲都是前所未有的。该恐龙足迹化石群主要包括了蜥脚类、兽脚类、鸟脚类、古鸟类和翼龙类足迹。这给我国恐龙足迹,以及古生态学,古环境学研究提供了丰富的实物材料,对我国西北地区的恐龙分布及其古地理研究也具有重要意义。 镰刀状足迹的多道行迹 镰刀状足迹与造迹者的关系-绘图张宗达   和世界上同类足迹一样,盐锅峡的蜥脚类恐龙足迹大体为圆形,前部均具有4或5个清晰的爪痕。它们完全符合中大型蜥脚类恐龙的特征,即巨龙类等等有着长脖子的巨大植食恐龙。然而,同层面上的多道蜥脚类足迹却显得“不正常”,它们看上去就像一把把巨大的镰刀,也就是只保存了后足的趾痕,没有脚跟,更没有前足足迹。   “没人觉得这些巨大的恐龙能单凭后腿走路的——那样它们肯定得摔倒。”主导研究项目的地质大学博士生、青年古生物学者邢立达说,“最终研究表明它们当时确实是在行走,因为这些镰刀状足迹与普通的蜥脚类后足迹的前部几乎一模一样。曾经有学者,甚至包括我们研究团队一些成员早期的观点,是认为恐龙当时正在游泳,其前肢浮在水中,而后肢向后划水,划水的时候其爪部接触水底,于是便在沉积物上留下了痕迹。” 普通的蜥脚类足迹   英国皇家兽医学院的彼得·弗金汉(Peter L. Falkingham)博士说道,镰刀状足迹化石的三维图像显示,当恐龙进入这片柔软的湖畔沙地时,其沉重的体重让它们与过软的沉积物较上了劲,其后肢的大爪子为增大抓地力而不得不深深地插入地面,此时被爪子挤出的大量沉积物往上与往后堆积,而盖住了后足迹的后半部,造成了镰刀状的形态。“此外,由于巨龙类恐龙的重心位于后半身,所以后足陷得更深,而前足的压力较弱,不足以制造出可以长期留存的足迹。”权威恐龙足迹学者马丁·洛克利(Martin G. Lockley)教授补充说。为了验证这个假说,研究者在各种软硬、粗细不同的沙滩上各种蹦跶,终于得到了非常类似的结果。   英国布里斯托尔大学的麦克·本顿(Mike Benton)院士则表示:“虽然我们排除了甘肃镰刀形足迹并非蜥脚类游泳的证据,但这并不是说蜥脚类就不会游泳。我们只是在深入研究足迹化石和沉积物的细节之后得到了不太浪漫的结果。也就是说,异常的后足迹和消失的前足迹,其原因归咎于沉积物变化,而不是恐龙的行为。”相关的主题文章: