Life Through Time

Abstract

The history of our Planet Earth, has passed through a series of very important events, but without a doubt one of the most spectacular events is the appearance of the life. The life in the past is represented by fossils, therefore, the science that studies fossils is Paleontology. The fossils provide infinite information to us, they are so important that it is the only way to interpret the Life Through Time, the fossil is the opened book of the life. The fossils are mainly in sedimentary rocks, but they can be on metamorphic rocks of very low temperature, or in igneous rocks, like volcanic ashes, but there are very few, also it is possible to found them in glaciers, amber or some chapopoteras. The fossils can be represented by tracks, marks, burrows, coprolites, molds, and the complete or fragmented forms. An impressive amount of fossils exists in the world, that are lodged in a registry, called “Fossil Record”. This fossil registry, is incomplete, but is sufficient to understand what happened in the past.The age of the planet Earth is calculate in about 4,600 million years, and the first fossils, correspond to microscopic organisms like bacteria, calcareous seaweed, that probably appeared about 3000 to 3800 million years ago, in a geologic time denominated Precambrian.