fosils of ancient times

how a science of 'natural' chemicals can give us a deeper knowledge of the science of 'social' that is history.
As an educated person, a little more knowledge we have received an inheritance from previous generations. By going to school, listen to the story of the history teacher, read a book, or watch a documentary, we are living in the 21st century so it can know about what is happening in the world starting from hundreds, thousands, even millions of years ago. But never not you think lo ... how the hell do I think the information chain is not interrupted?
For events that are still 'new' occurs tens to hundreds of years ago, historians still be relied on article / journal written by a past civilization, whether it is engraved in the inscription or temples, written on palm leaves, stem of trees, wood fiber, the walls of caves, etc.
But what about our knowledge of the life of pre-history when man has not been able to "speak" of its existence in the form of pictures or writing? Where the hell of scientists arkeologist, palentologist, and geologists can know about the condition of the world in the past so we know that millions of years ago it was a dinosaur, no ancient humans, there was a giant shark (megalodon),
As probably most of us know, the main source of information for scientists to probe life on a pre-historic fossil finds. Fossils in a sense is the remains or traces of living things of the past are preserved naturally can indeed provide much information to us who live in the modern era of the living conditions in the past. From the start when the fossilized living beings who live, what form, how the system works the body, until the environmental conditions at the time of the creature living