I shouldn't have given all the props to chicks for being able to count. Turns out mosquitofish -- freshwater fish found in north and central America -- can count as well, and the test they passed to indicate this reminds me of the scene in Labyrinth where Sarah has to determine which door to enter.
Also in today's links: how to grind rock without damaging your teeth, a fond memory for all former Odyssey-of-the-Minders, and more.
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Science is reinventing play, from extreme sports to gamification to ridiculous roller coasters to the playgrounds of tomorrow, and this issue is chock full of fun. Also, on a less fun note: Did global warming destroy my hometown?