PBS Member Stations rely on viewers like you. To support your local station, go to: http://to.pbs.org/DonateOKAY ↓ More info and sources below ↓ We’re on PATREON! Join the community ►► https://www.patreon.com/itsokaytobesmart SUBSCRIBE so you don’t miss a video! ►► http://bit.ly/iotbs_sub Could humans ever evolve to have wings? Why don’t fish have propellers? Why don’t tigers have wheels? Why don’t zebras have laser turrets? These might all seem like stupid questions (and maybe they are!) but they can teach us a lot about how evolution actually works, and how it doesn’t work. References: https://sites.google.com/view/whatisimpossible-references/home ----------- Big Thank you to our Brain Trust Patrons: Roy Lasris Javier Soto dani bowman David Johnston Ahmed Elkhanany Zenimal Salih Arslan Baerbel Winkler Robert Young Amy Sowada Benjamin Teinby Eric Meer Jay Stephens Peter Ehrnstrom Dustin Marcus Tuepker Karen Haskell AlecZero Diego Lombeida Join us on Patreon! https://patreon.com/itsokaytobesmart Twitter http://www.twitter.com/DrJoeHanson http://www.twitter.com/okaytobesmart Instagram http://www.instagram.com/DrJoeHanson http://www.instagram.com/okaytobesmart Merch null Facebook https://www.facebook.com/itsokaytobesmartpbs/