What makes yawning so contagious? Watch the 'Yawn-O-Meter': http://bit.ly/1qwFDrx SUBSCRIBE: http://bit.ly/10kWnZ7 Instagram and Twitter: @whalewatchmeplz and @mitchellmoffit Clickable: http://bit.ly/16F1jeC and http://bit.ly/15J7ube Facebook: http://on.fb.me/1fjWszw Twitter: http://bit.ly/1d84R71 Tumblr: http://bit.ly/1amIPjF Vine: Search "AsapSCIENCE" on vine! Written and created by Mitchell Moffit (twitter @mitchellmoffit) and Gregory Brown (twitter @whalewatchmeplz). Further Reading -- Yawning as a Brain Cooling Mechanism: http://www.albany.edu/news/pdf_files/Yawning_Report_Gallup_May_2007.pdf Chimpanzees and contagious yawning: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3534187/ Familiarity-connected or stress-based contagious yawning in domestic dogs: http://www.ncbi.nlm.nih.gov/pubmed/23982621 Contagious yawning, social cognition, and arousal: an investigation of the processes underlying shelter dogs' responses to human yawns: http://www.ncbi.nlm.nih.gov/pubmed/23670215 The thermoregulatory theory of yawning: http://www.ncbi.nlm.nih.gov/pubmed/23293583 Male yawning is more contagious than female yawning among chimpanzees: http://www.ncbi.nlm.nih.gov/pubmed/22808234 Mirror neuron activity during contagious yawning--an fMRI study: http://www.ncbi.nlm.nih.gov/pubmed/22772979 Thermoregulatory theory of yawning: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3534187/