Is sign language left or right handed? Can it be mirrored without losing its m‘’ looks through the lens of CHRISTMAS LECTURES past to share the best demonstrations around the science of communication. From Attenborough and Sagan to Woollard and Fong, we revisit old favourites and find new gems to bring you a little gift of science every day in the lead up to Christmas. http://bit.ly/RiAdvent17 The Ri is on Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and Tumblr: http://ri-science.tumblr.com/ Our editorial policy: http://www.rigb.org/home/editorial-policy Subscribe for the latest science videos: http://bit.ly/RiNewsletter