Why Don't Other Animals Use Glasses?

Viewers like you help make PBS (Thank you 😃) . Support your local PBS Member Station here: https://to.pbs.org/PBSDSDonate Check out The Great Courses Plus: http://ow.ly/OE9y301cRfI Don’t miss our next video! SUBSCRIBE! ►► http://bit.ly/iotbs_sub ↓ More info and sources below ↓ Get yourself an awesome IOTBS shirt! http://dftba.com/besmart This is a cool old movie from 1941 about how the eye works: https://archive.org/details/0586_How_the_Eye_Functions_E00456_04_22_16_00 Dive deeper into the physics of vision correction with Michel van Biezen: https://www.youtube.com/playlist?list=PLX2gX-ftPVXXf2ZaG_1SXAYbVcifI6gvr Myopia boom in modern times: http://www.nature.com/news/the-myopia-boom-1.17120 Limits to human vision: http://www.ncbi.nlm.nih.gov/pubmed/11019869 ---- Have an idea for an episode or an amazing science question you want answered? Leave a comment or check us out at the links below! Like us on Facebook: http://www.facebook.com/itsokaytobesmart Follow on Twitter: http://twitter.com/okaytobesmart http://twitter.com/jtotheizzoe Follow on Tumblr: http://www.itsokaytobesmart.com Follow on Instagram: http://instagram.com/jtotheizzoe Follow on Snapchat: YoDrJoe ----------------- It’s Okay To Be Smart is written and hosted by Joe Hanson, Ph.D. Follow me on Twitter: @jtotheizzoe Produced by PBS Digital Studios: http://www.youtube.com/user/pbsdigitalstudios Music via APM Stock images from SciencePhoto http://www.sciencephoto.com/ and Shutterstock http://www.shutterstock.com Stock footage from Videoblocks (unless otherwise noted) http://www.videoblocks.com Learn more about your ad choices. Visit megaphone.fm/adchoices