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TF阅读真题第746篇Oceanic Bird Navigation
Migratory birds are well known to navigate over long distances between feeding grounds and breeding sites, often over thousands of miles. Ornithologist G. V. T. Matthews dem...
TF阅读真题第745篇Centralized Societies: Archaeological Evidence
When studying an archaeological site, archaeologists must first try to understand how the society that lived there was organized. Some societies are centrally organized, and...
TF阅读真题第744篇The K/T Boundary
In the late 1970s, several research groups were trying to determine the cause of the boundary between the geological layers corresponding to the Cretaceous and Tertiary periods, ab...
TF阅读真题第743篇Rural Manufacture
The growing population of eighteenth-century Europe increased demand for cloth to clothe people. Urban merchants turned to rural people for additional, inexpensive labor: farming f...
TF阅读真题第742篇Measuring Climate Change on Mountains
Climate change has been linked to greenhouse gases in Earth's atmosphere that allow sunlight to reach the planet's surface while trapping the infrared energy that it emits...
TF阅读真题第741篇Silver in North America in the Late Eighteenth Century
Silver and silver objects had multiple meanings in late-eighteenth-century North America. Insights about social attitudes and the buying habits of consumers come partly from the re...
TF阅读真题第740篇Economic Decline of the Roman Empire
The Roman Empire(31 B.C.E.-A.D. 476)， which conquered much of Europe, the Near East, and northern Africa, enjoyed great prosperity before facing economic decline in its later cent...
TF阅读真题第739篇The Formation of Moons
All planets in the solar system except Venus and Mercury have at least one moon orbiting them,with the two largest jovian (giant) planets,Jupiter and Saturn,each having over sixty....
TF阅读真题第738篇Sauropods and Conifers
The sauropod dinosaurs were gigantic, long-necked herbivores (plant eaters) that flourished during the Jurassic period (201-145 million years ago). At the same time that the saurop...
