You Are An Upside-Down Lobster

Viewers like you help make PBS (Thank you ?) . Support your local PBS Member Station here: https://to.pbs.org/PBSDSDonate Here's why you aren't built like a lobster. Subscribe to It's Okay To Be Smart: http://bit.ly/iotbs_sub ↓ More info and sources below ↓ Follow on Twitter: http://twitter.com/jtotheizzoe Follow on Tumblr: http://www.itsokaytobesmart.com Our bodies are mirror images of lobsters and other arthropods from back to belly. We've know since the early 19th century that our guts and nervous systems are inverted from theirs, but only recently has molecular biology shown us why. Here's the evolutionary tale about a worm doing the backstroke and why your guts are on your front This is part 2 of 3 in my series about how our bodies evolved to look like they do. Check out the others: Part 1 - https://www.youtube.com/watch?v=qdNE4WygyAk Part 3 - Coming Friday! More info: Dorsoventral inversion: http://en.wikipedia.org/wiki/Inversion_(evolutionary_biology) Geoffrey Saint-Hilaire: http://en.wikipedia.org/wiki/%C3%89tienne_Geoffroy_Saint-Hilaire Common animal body plan between protostomes and deuterostomes: http://www.hhmi.ucla.edu/derobertis/EDR_MS/Evo-Devo_page/EVO-DEVO.html How we know that our body plan came later: http://scienceblogs.com/pharyngula/2006/01/12/hemichordate-evodevo/ Step by step along the evolutionary tree: http://tolweb.org/Bilateria/2459 http://en.wikipedia.org/wiki/Bilateria http://en.wikipedia.org/wiki/Deuterostome http://en.wikipedia.org/wiki/Protostome http://en.wikipedia.org/wiki/Urochordata http://en.wikipedia.org/wiki/Chordate http://en.wikipedia.org/wiki/Cephalochordata http://en.wikipedia.org/wiki/Craniate http://en.wikipedia.org/wiki/Gnathostomata Evolutionary timeline of vertebrates: http://www.utexas.edu/news/2008/03/03/tree/ ----------------- Have an idea for an episode or an amazing science question you want answered? Leave a comment below! Follow me on Twitter: @jtotheizzoe Email me: itsokaytobesmart AT gmail DOT com Facebook: http://www.facebook.com/itsokaytobesmart Google+ https://plus.google.com/+itsokaytobesmart For more awesome science, check out: http://www.itsokaytobesmart.com Joe Hanson - Host and writer Joe Nicolosi - Director Amanda Fox - Producer, Spotzen IncKate Eads - Associate Producer Katie Graham - Director of Photography Andrew Matthews - Editor and motion graphics John Knudsen - Gaffer Music: "Ouroboros" by Kevin MacLeod Stock images via Shutterstock Produced by PBS Digital Studios: http://www.youtube.com/user/pbsdigitalstudios ----------- Last week's video: Why Did We Blow on NES Games? https://www.youtube.com/watch?v=4Gf9mtXnJfM More videos: The Science of BBQ https://www.youtube.com/watch?v=ccqOVmsybO4 The Science of Game of Thrones - https://www.youtube.com/watch?v=Utu-LpJn3Is The Far Future of the Universe - https://www.youtube.com/watch?v=Jl9DwNOonOA There Was No First Human - https://www.youtube.com/watch?v=xdWLhXi24Mo How The Elements Got Their Names - https://www.youtube.com/watch?v=mtg9p6A6xnY