In the video today, we're looking at why humans kiss and whether this is a learned behavior or something more or less built in. In the Bonus Facts, we're looking at how the practice of kissing under the mistletoe got started. If you'd like the text version of this video and references, you can find that here: http://www.todayifoundout.com/index.php/2014/06/kiss/ and http://www.todayifoundout.com/index.php/2010/12/the-word-mistletoe-literally-means-dung-twig/