July 25, 2011 at 7:30 PM ET
The rise of kitty videos, baby pictures and other cuteness on the Internet is now explained by our hardwired instinct to share when we care.
Jonah Lehrer writes at the Wall Street Journal about a study by a Wharton prof, Jonah Berger, which showed that when people are emotionally tickled or rattled, they're much more likely to share news.
It all comes down to a primal instinct. Psychologists will tell us that when we're scared, amazed, or angry, our first response is to reach out to other human beings. "If I'm angry, and then you get angry, we can bond over what we're feeling," Berger told Lehrer.
On the Internet, this is harder to do, so people scratch that same impulse by popping the link in an email and sharing it around.
The "Charlie Bit My Finger — Again!" video, above, with 350 million views now is a prime example, Lehrer explains. The teething toddler and his cheeky older brother are adorable, and go through a rainbow spectrum of emotions through the 56-second vid.
Our empathetic selves follow along as we watch, experiencing the same hormonal flushes and ebbs that make the kids happy, angry, and gleeful. That's when the ache to share hits, and before we know it, we're sharing links on Google+ and Facebook pages and tweeting madly.
Finally, evidence that cuteness is contagious.
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