Reading audio By VOAMay 18, 2014抱歉，本篇不提供文本。 Category Technology Report Related reading: App Identifies Birds by Sound How Did Human Ancestors Lose Their Tails? Study: Ozone Pollutants Still Increasing in Northern Hemisphere A Small Packet of Chemicals, a Big Effect on Dirty Water NASA Finds Evidence of Carbon Dioxide in Exoplanet Atmosphere