对被认为仅仅含有一只有翼恐龙的羽毛痕迹的化石的重新检查可能显示出把鸟类和恐龙联系起来的羽毛残余。Roy Wogelius及其同事用极化X射线为已知最早的鸟类——始祖鸟的化石拍照，并生成了这一化石的高分辨率化学图。始祖鸟显示出了和鸟类（羽毛）与恐龙（牙齿）共有的特征。
这组科学家使用了一种同步辐射X射线装置，用强烈但是非损伤性的X射线扫描这个样本，从而分析它的结构和化学成分。这项检查显示出这些羽毛的元素组成不同于周围的岩石，这表明石化羽毛物质的残余仍然存在于这个标本中。这项发现与此前的分析相反。此前的分析得出结论认为这种鸟的可见羽毛仅仅是压痕。
这些化学图可能提供这种动物的石化与保存是如何发生的线索，并为这一化石在发现之后的历史提供见解。这组作者说，这种技术还可能促进生物分子提取、检验造假等学科，还能促进对古代文件的检验。（生物谷Bioon.com）
生物谷推荐原文出处：
PNAS doi: 10.1073/pnas.1001569107
Archaeopteryx feathers and bone chemistry fully revealed via synchrotron imaging
U. Bergmanna, R. W. Mortonb, P. L. Manningc,d, W. I. Sellerse, S. Farrarf, K. G. Huntleyb, R. A. Wogeliusc,g,1, and P. Larsonc,f
aStanford Linear Accelerator Center National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, CA 94025;
bChildren of the Middle Waters Institute, Bartlesville, OK, 74003;
cSchool of Earth, Atmospheric, and Environmental Sciences, University of Manchester, Manchester, M13 9PL, United Kingdom;
dDepartment of Earth and Environmental Sciences, University of Pennsylvania, Philadelphia, PA, 19104;
eFaculty of Life Sciences, University of Manchester, Manchester, M13 9PT, United Kingdom;
fBlack Hills Institute of Geological Research, Inc., Hill City, SD, 57745; and
gWilliamson Research Centre for Molecular Environmental Science, University of Manchester, Manchester, M13 9PL, United Kingdom
Evolution of flight in maniraptoran dinosaurs is marked by the acquisition of distinct avian characters, such as feathers, as seen in Archaeopteryx from the Solnhofen limestone. These rare fossils were pivotal in confirming the dinosauria-avian lineage. One of the key derived avian characters is the possession of feathers, details of which were remarkably preserved in the Lagerst?tte environment. These structures were previously simply assumed to be impressions; however, a detailed chemical analysis has, until now, never been completed on any Archaeopteryx specimen. Here we present chemical imaging via synchrotron rapid scanning X-ray fluorescence (SRS-XRF) of the Thermopolis Archaeopteryx, which shows that portions of the feathers are not impressions but are in fact remnant body fossil structures, maintaining elemental compositions that are completely different from the embedding geological matrix. Our results indicate phosphorous and sulfur retention in soft tissue as well as trace metal (Zn and Cu) retention in bone. Other previously unknown chemical details of Archaeopteryx are also revealed in this study including: bone chemistry, taphonomy (fossilization process), and curation artifacts. SRS-XRF represents a major advancement in the study of the life chemistry and fossilization processes of Archaeopteryx and other extinct organisms because it is now practical to image the chemistry of large specimens rapidly at concentration levels of parts per million. This technique has wider application to the archaeological, forensic, and biological sciences, enabling the mapping of “unseen” compounds critical to understanding biological structures, modes of preservation, and environmental context.
