Erratics and Drift   In the nineteenth century, scientists theorized that glaciers (ice sheets) covered much of Earth's surface during an ancient very cold period known as the...

TF阅读真题第850篇The Australian Megafauna Extinctions

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 ...

The Nile River Valley Though the verdant green course of the Nile Valley appears to be the very antithesis of the bleached Saharan sands through which it flows, these two contras...

Diving for Food by Birds     Seabirds are physiologically adapted to dive underwater for food, a strategy that necessarily poses problems. An obvious problem is that whe...

复时间 2022-09-28 2023-12-13 2024-04-13 2025-04-12 Adaptations of Marine Mammals     Warm-blooded marine mammals and birds require some special adaptations to permit t...

Opera in Seventeenth-Century Venice     Opera, a form of drama set to music and featuring vocal performance supported by an orchestra, was born in Italy at the very end ...

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...

复时间 2022-06-07 2025-04-12 Early Domestication and Agriculture     To some extent, the causes of agriculture are to be found in the thousands of years of hunting-ga...

  题目： Living-History Museums in the United States       The living-history approach to teaching social history combines restored or re-created historical ...