Jazz   Jazz music, an art form original to the United States, originated in the southern city of New Orleans at the turn of the twentieth century. It combined the elements of ...

Mars's Disappearing Atmosphere   For about the first billion years of its life, Mars was probably a watery planet. There are signs of past water in surface features, such as d...

Reconstructing the Spread of the Grain Weevil Perhaps the most common, most widespread, and arguably most destructive pest of stored grain in history is the grain weevil Sitophilu...

Tyrannosaurus rex: Predator or Scavenger? Tyrannosaurus rex was among the largest of the theropods, a group of mostly carnivorous (meat-eating) dinosaurs that roamed the Earth dur...

How Fossils Map the Past     Only a tiny fraction of the organisms that have lived during the geologic past have been preserved as fossils.Normally the remains of an ani...

TF阅读真题第833篇The Radiocarbon Dating of Prehistoric American Sites

The Origin of Mars's Moons     Mars has two tiny moons, Phobos and Deimos. The orbits of both these satellites are nearly circular and close to the planet: Phobos orbits...

The Moon's Origin   One of the earliest scientific theories about the Moon's origin postulated that Earth and its moon formed out of a dust cloud alongside one another, much a...

TF阅读真题第834篇Group living

TF阅读真题第875篇Life in the Desert   Life in the Desert     In the austere and inhospitable environment of the desert, each inhabitant must be highly specialized ...