When evolution favours a stable ratio of traits rather than one dominant trait.
Check out Audible: http://bit.ly/AudibleVe
Animation by The Lyosacks: https://www.youtube.com/TheLyosacks
Hosting Neil Degrasse Tyson, info and tickets: http://bit.ly/NDTandVe
Aug. 22 in Sydney
Aug. 23 in Canberra
Special thanks to Richard Dawkins
Filmed at Academia Film Olomouc with help from Martyn Marek
Music by Kevin MacLeod www.incompetech.com 'Marty Gots a Plan' 'Sing Along with Jim'