Traffic Lights Are So Much Weirder Than You Realize

Thank you to Squarespace for supporting PBS. Go to https://www.squarespace.com/besmart for a free trial and use code BESMART to save 10% off your first purchase of a website or domain. ↓↓↓ More info and sources below ↓↓↓ Why are stop lights red? The common explanation about red light traveling farther through fog is actually wrong. The real story involves early railroads, deadly accidents, an exploding gas traffic light, forgotten inventors, and even the evolution of primate color vision. Here’s how history and biology accidentally created the nearly perfect traffic signal. ____________________________________ Be Smart explores science questions you didn’t even know you wondered about. It is hosted and produced by Joe Hanson, PhD. We post new videos all the time, so please subscribe! If you enjoyed this video, hit the ‘like’ button, leave a comment, or watch another of our videos! CONNECT WITH ME ____________________________________ Website: https://www.itsokaytobesmart.com/ Instagram: https://www.instagram.com/okaytobesmart/ https://www.instagram.com/drjoehanson/ Facebook: https://www.facebook.com/itsokaytobesmart Patreon: https://www.patreon.com/c/itsokaytobesmart High fives to all our Brain Trust Patrons: Baerbel Winkler, Brent Lopez, dani bowman, David Johnston, Ed Eyden, Eric Meer, Holly, Brett, and Ashe Bullion, Jaap Westera, Karen Haskell, Marcus Pingel, Mike and Patty Loftis, Olivia Ruiz, Paul Weir, Reuben Brewer SPONSORSHIP INQUIRIES ____________________________________ Please email [email protected] Stock video and images provided by Shutterstock, Artlist, and MotionArray Music provided by APM Written by Joe Hanson Edited by PW Shelton Produced by Least Square Media and Spotzen for PBS Digital Studios