How does the durationm of human life on earth compare with of the dinosaurs?

The best analogy I have ever heard to really put this into perspective is written in Louie Psihoyos And John Knoebber's book Hunting Dinosaurs:

"Kevin Padian of the University of California at Berkley uses the following analogy to give his students a Deep Time perspective. 'If you take the history of life as the length of your arm, then one stroke of a nail file erases human history.'

Putting it another way, geology professor Don L. Eicher came up with this brilliant analogy of compressing the Earth's history into one calendar year. With some of my own updated and twisted additions we find that on

January 1: The Earth begins.

Springtime, March 20: The Birthday of DNA. The first one-celled bacteria, bobbing happily in the muck, re-creates itself. All lifeforms thereafter will be stamped with this same DNA.

Thanksgiving: Sea Creatures begin pioneering the land.

December 11: 90 percent of all life forms go extinct.

December 13: Dinosaurs enter.

The day after Christmas: Dinosaurs go extinct.

The evening of December 31: Manlike creatures appear.

December 31 11:59:45 to 11:59:50: Roman Empire rises and falls.

3.5 seconds to midnight: Columbus discovers America (or, if you wish, Indians discover Columbus)

1/20th of a second to midnight: The Beatles play the Ed Sullivan Show."

(This excerpt copyright Louie Psihoyos, Hunting Dinosaurs, published by Random House in 1994)

Yes, I know. I suck at citing my sources. Credit was given, and all required information is there. Leave me alone. >.<