In terms of evolution, there has to be a reason for barking, or it probably wouldn't be there. 从进化的角度而言，狗汪汪叫肯定是有理由的，要不这叫声肯定在漫长的进化过程中给淘汰掉了。 Is it to warn of predator...
Now, a few tens of thousands of years ago, wolves and people started becoming friendly species. 时至今日，数万年前，狼和人便慢慢演变成进化成为可以友好相处。 You can imagine a person tossing a bone to a friendly wolf from...
What makes adolescents so vulnerable to developing addictions to substances like nicotine, alcohol, and drugs? 是什么使得青少年轻而易举就沾染尼古丁，酒精及毒品？ More vulnerable than any other age group. 尤其是青少年，他...
That may not sound so bad in theory, but downside about this region of the brain is that along with adolescent inhibitions may come experimentation and abuse of addictive drugs. 这听起来可能不是那样糟糕，但这个区域的真正缺点是随...
So you want to attract a mate. 那你是想吸引配偶喽！ After all, passing on your genes is what evolution is all about. 毕竟基因传递才是进化的意义！ To do that you need offspring, and to get a lot of those you need to be attracti...
Researcher Molly Cummings and her coworkers at the University of Texas at Austin placed afemale swordtail in a tank with two males visible at either end. 来自德克萨斯大学奥斯汀分校的研究员莫莉卡明斯和她的同事们做了一个有...
You can see the planet Jupiter on a clear night, but Jupiter is humongous. 在晴朗的夜空下我们能够看到木星，那是因为木星够大； Mars and Mercury are smaller than that, and you can see them, too. 尽管火星和水星比木星要小...
Vesta is quite far away. 灶神星距地球的距离很远。 Like many asteroids, it has an orbit out between the orbits of Mars and Jupiter. 像其它许多小行星一样，它在火星与木星之间有自己的运行轨道。 Astronomers first s...
Remember that kid in your grade school class who stuttered? 还记得小学时班上那个说话结巴的孩子吗？ Well, he was in good companya whopping three million people in the United States alone are affected by this problem. 其实，他的同...
With the age of electronics, it was found that hearing your own voice played back to you almost as soon as you speak helps a stutter as well. 人们发现，如果在说话时能够几乎同步地听到自己所说的内容会有助于减缓口吃。...
Did you ever stopped to wonder why sex and violence so often go hand in hand? 你有没有静下来思考过，为什么性和暴力总是联系在一起呢？ How come nobody complains about violence and gardening, say, or sex and bowling? 为什么没...
Some of the behaviors appropriate for sex are apparently similar to those for aggression, and the two can become confused. 显然，动物的一些交配行为与暴力行为相似，并且二者极易混淆。 Another example is tropical fish, which...
Have you ever wondered why fluorescent colors, like you see in highlighters or clothing dyes, for instance, seem so much brighter than other colors? 你是否好奇为什么荧光色如荧光笔或服装染料的颜色似乎比其他颜色鲜亮许多？...
Ultraviolet light, or UV, is just beyond visible violet in the spectrum. 紫外线（UV）频率恰好在可见紫色光之外。 Its wavelength is too short to be visible to the naked eye, but you see it working when fluorescent colors glow! 紫外线...
Fira is a typical Greek city overlooking the Aegean Sea. 菲拉是一座典型的希腊城市，在这里可以俯瞰爱琴海。 Sitting atop a twelve hundred foot cliff on Santorini Island, its an ideal vacation spot. 这座城市坐落在圣托里尼...
