Puppies tussle in the annual Puppy Bowl. Kids start a game of tag in a schoolyard. Play has been observed and documented in many species — and not just in mammals. However, according to Dr. Michael ...

At parties and bars, he introduces himself as a “rat tickler.” The title makes Shimpei Ishiyama sound like he belongs in some forgotten guild of yore, with the Victorian “pure-finders,” who collected ...

A new study is linking brain behavior to silly playtime practices. And they have lab rats laughing out loud to prove it.In the video above, you can hear tiny high-pitched giggles from a rat being ...

Freelance writer Amanda C. Kooser covers gadgets and tech news with a twist for CNET. When not wallowing in weird gear and iPad apps for cats, she can be found tinkering with her 1956 DeSoto. Rat ...

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