Life is the condition that segregates organic matter such as plants and animals from inorganic matter such as rocks. Life includes growth, replication, funcional acivity and, eventually and inevitably, death.
The origin of life remains the greatest mystery to scientists. Carbon isotope signatures that appear to have been produced by living organisms were found in sediment depositions in Greenland and dated 3.8 billion years old. The oldest rocks with fossil evidence of life on earth are 3.5 billion years old.
Several mass extinction occurred that wiped out most of the species of life on earth. The last one occurred 65 million years ago, when dinosaurs became extinct.
