The Origin of Flight in Birds 题目： Debate over avian origins was stimulated in 1861 when the 150-million-year-old fossil of a bird-like creature was unearthed. Called Archaeopt...

题目： Prairie Diversity 1 Prairies—the grasslands that once covered immense areas of central North America—were created and maintained by factors that favored the growth of g...

TF阅读真题第845篇Urbanization of Japan

  The seventeenth century was a golden age for Dutch painting, with artists producing genre paintings (depictions of scenes from everyday life), still lifes of fruit or flower...

TF阅读真题第689篇Natufians and the Domestication of Grain

The Birth of the Solar System The Birth of the Solar System     题目：   Scientists believe that the sun and the planets in our solar system formed from a vast clo...

TF阅读真题第724篇Modern lnuit Commercial Arts

The Greek City-States: Sparta and Athens Of the hundreds of city-states that evolved during the Archaic Age, (800- 479 B.C.), Sparta and Athens stand out for their vividly contras...

  Making the Most of Dark Nights       The main breeding station of the marine bird known as the swallow-tailed gull is the Galápagos Islands, which straddle...

  Archaeoptertx and Flight 题目： It is not known whether Archaeopteryx, the earliest birdlike creature for which fossils have been found, could fly-but it probably did, at ...