我们的生活中总是存在着一些非常流行的科学理论或说法。实际上，在这些理论当中，有的确实如此，有的却是人们的错误理解。日前，美国“生活科学网”就对这些问题进行了归纳总结。

　　Chickens can live without a head. 鸡没有脑袋也能存活

    True, and not just for a few minutes. A chicken can stagger around without its noggin because the brain stem, often left partially¹ intact after a beheading, controls most of its reflexes. One robust² fellow lived a full eighteen months. Likely he was a real birdbrain, however.

　　正确！而且鸡在被“斩首”之后绝不只是能“苟延残喘”几分钟而已。事实证明，曾有一只精力充沛的家伙在被斩首后，居然摇摇摆摆、跌跌撞撞地活了整整18个月！

    Humans use only 10 percent of their brains. 人类的大脑只开发了十分之一

    This media darling has been around for at least a century. Fortunately, it's just not true. MRI imaging clearly demonstrates—with fancy colors no less—that humans put most of their cerebral³ cortex to good use, even while dozing⁴.

　　这一被媒体广泛关注的理论已至少存在了1个世纪。但幸运的是，这个理论并不正确。核磁共振图象明确地显示出，即使是在打瞌睡的时候，人们都很好地利用了其大部分的大脑皮层，人脑并没有被荒废。

    Water drains backwards⁵ in the Southern Hemisphere due to the Earth's rotation⁶. 地球自转致使南半球水流旋涡呈逆时针旋转

    Not only is the Earth's rotation too weak to affect the direction of water flowing in a drain, tests you can easily perform in a few washrooms will show that water whirlpools both ways depending on the sink's structure, not the hemisphere.

　　其实，地球自转的作用很微弱，因此难以影响水流动的方向。你可以在一些盥洗室中轻易地验证这一点，无论是逆时针还是顺时针，水流旋涡的方向取决于水槽的结构，而非南北半球。

    There is no gravity in space. 太空无重力

  Blame the term "zero-gravity" for this common misconception. Gravity is everywhere, even in space. Astronauts look weightless because they are in continuous freefall towards the Earth, staying aloft because of their horizontal motion. The effect of gravity diminishes with distance, but it never truly goes away. Oh, and while we're at it, it's also untrue that space is a vacuum. There are all kinds of atoms out there, albeit⁷ sometimes far apart (and this thin gas adds to the collective gravity budget, too!)

　　这是个普遍的误解，事实上重力无处不在，即使在太空也是如此。宇航员之所以看起来无重力是由于他们处于向地球的持续下落中，而保持高高在上则是由于他们的水平运动所致。重力的影响会随远离而减小，但它绝不会真正地消失殆尽。