<http://schema.org/alternativeHeadline>
"It's not yet clear what dogs feel when they're yawning, but about half the dogs in the study became calmer following yawns."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/family/pets/stories/puppies-learn-to-catch-yawns-as-they-grow>