Sometimes it's difficult to imagine the hard road our prehistoric ancestors took to populate all of the continents. One Sunday, my wife and I decided to go to the Fernbank Museum of Natural History in Atlanta. It's a great place to take your kids if you want good illustrations to help them learn about the biological timeline of life on Earth, or if you just want them to learn everything there is to know about feces. While we were wandering through the history of Earth, we found a room with an interesting item: a world map, covered in snaking arteries of tiny light bulbs. When you pressed the button to activate the exhibit, the light bulbs would grow bright in a chronological succession, spreading out from the Olduvai Gorge in Eastern Africa, where human life is believed to have begun, up into Northern Africa, through the Middle East, to Europe and Asia, across the Bering Strait to the American continents, down to Australia and the Pacific Islands, and eventually to reach all of the corners of the globe. No matter who you are, no matter how strong and confident, it seems like you have to reckon the sheer unlikeliness of your existence. Think about it: Every human -- every CREATURE! -- that is in your family tree had to be born alive, had to compete against harsh environments and conflict to survive, had to successfully reproduce, and had to ensure the survival of its young offspring, for you to eventually get here. Compared to the one way you actually did come to exist, there are an infinite number of ways you could have been extinguished before you were born -- if your great(x437)-grandmother had gotten lost in the wilderness, died young, and never given birth to your great(x436)-grandmother -- if your great(x614)-grandmother had never met your great(x614)-grandfather, and so on. You're forced to wonder how parents cared for dependent children when food was scarce, how they found time to foster family relationships when migrating from one tough climate to another. And how each of the individually unlikely successes somehow piled upon another to produce each person today. In the museum, I was overcome again by this striking feeling as I watched the lights take their course. After I had seen the whole thing, I stepped back to wait on my wife, who was looking at something else. A man and his young daughter approached the human migration map. The father pressed the button and the daughter watched. As each new step in the great mass migration illuminated, he tried to read her the accompanying text. And let's face it -- for all the clichés we sling about having a "childlike sense of wonder" or the "curiosity of a child," most of the time, kids have a hard time paying attention. I think perhaps they're not always as intellectually thirsty as we give them credit for. But when the little girl's father lost her attention, he waited for the lights to finish their course, and then he started again. They got a little farther. Then she began to look at other people. She looked at other kids, and she looked at me. Her father noticed, and he waited, and he pressed the button again. When they got to the end, and she saw what had happened, and he saw that she saw, he said, "Isn't that cool?" She said it was. And they traveled on to the next exhibit.
