28 mayo 2015
Have you ever caught yourself yawning right after someone else did? The same happens to budgies. Biologists have just noted that contagious yawning also occurs between members of a bird species. Contagious yawning was previously thought only to occur between humans, domestic dogs, chimpanzees and a type of rodent aptly called the high-yawning Sprague-Dawley rat.
http://feeds.sciencedaily.com/~r/sciencedaily/~3/sQJrIVipD6k/150528083830.htm
