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...

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...

听力音频： https://mp.weixin.qq.com/s/l60NYyttDfg2itptnygLRA?token=1029705590&lang=zh_CN   L3： Lecture 3 第一题 What is the lecture mainly about? AThe discovery of p...

  Sunspot Cycles   Dark regions on the Sun, called sunspots, were studied in 1610 by Galileo, who turned the newly invented telescope on objects in the sky. A lively deba...

TF阅读真题第806篇Maya Population in the Classic Period

Early Food Production in Africa   Farming appeared in Africa by 5000 B.c.E. Eventually, several different styles of food production developed. These variations were caused by ...

TF阅读真题第834篇Group living

  Sensory Ecology     Some of the most important sensory information animals have to process comes from other animals. Interactions between predators and prey, pare...

TF阅读真题第814篇Agriculture in Colonial New England

    综合写作：   Reading： The black robin is a small bird native to the islands of New Zealand. Several decades ago, black robins almost died out. Although the fu...