<p>Seabird poop plays a surprising role in bringing life to barren islands, spreading nutrients throughout the ocean, and even creating wealth for an ancient human empire.</p><p><br></p><p>PLUS:</p><p><br></p><ul><li>The precursors of written language go back a lot earlier than we thought</li><li>Dolphins exposed to the Deepwater Horizon oil spill also more likely to be hit by boats</li><li>From the archives: Canadian astronomer spots a supernova visible to the naked eye</li><li>Quirks Question: How do beavers choose their trees?</li><li>Mapping the universe in three dimensions</li></ul>