A lot of twists and turns went into the rise of homo sapiens. But was the die cast at the very moment, 14 billion years ago, that the universe decided to erupt from a singularity into a space that is now 90-billion light-years in diameter? Was it from that moment on unavoidable that sentient creatures would arise with two arms and two legs and a taste for ice cream? Science has gotten a lot closer to an answer and has found more and more links in a chain that takes us from the present back to the dawn of life. Our very bodies bear evidence of all sorts of shifts and upheavals in the cosmos—if you know what to look for. One person who can see all that evidence is University of Chicago paleontologist Neil Shubin, author of The Universe Within: Discovering the Common History of Rocks, Planets, and People. Shubin visits Zócalo to give a condensed astronomical, geological, and biological history of the world from 14 billion B.C. to the present—and to tell us what it should mean to us today.