Hank explains speciation - the evolutionary process by which new biological species arise - in terms of finches, ligers, mules, and dogs. Like CrashCourse on Facebook: www.facebook.com/youtubecrashcourse Follow CrashCourse on Twitter: www.twitter.com/thecrashcourse References for this episode can be found in the Google document here: dft.ba/-2DnD Table of Contents 1) Species 0:30 2) Hybrids 1:52 3) Reproductive Isolation 2:48 a) Post-Zygotic 3:31 b) Pre-Zygotic 3:51 4) Allopatric Speciation 4:23 5) Sympatric Speciation 6:03 6) Biolography 6:32 7) Dogs 8:37 This video contains the following sounds from Freesound.org: "bird tweet.aif" by tigersound "ForestBirds.wav" by HerbertBoland "morning_in_the_forest_2007_04_15.wav" by reinsamba "AMBIENT LOOP - Perfectly Clear - Wilderness Hillside - FILTERED.mp3" by Arctura "oceanwavescrushing.wav" by Luftrum biology, speciation, science, species, evolution, homo sapiens, organism, liger, napoleon dynamite, fertile, sterile, hybrid, hybridization, reproductive isolation, genetic isolation, pre-zygotic isolation, behavior, geographic, allopatric speciation, natural selection, galapagos, finch, artificial selection, corgi, greyhound, puppy, dog Support CrashCourse on Subbable: subbable.com/crashcourse