The age of our planet is 4.54 billion years. The history of life on it began with the appearance of the first living creature - 3.7 billion years ago - and continues to this day. About 1200 million years ago the first algae appeared, and already about 450 million years ago the first higher plants appeared. Invertebrates appeared in the Ediacaran period, and vertebrates arose about 525 million years ago during the Cambrian explosion. How was the Universe born? What happened before the Big Bang? Did life come to Earth from space? What animal was the first on Earth? Where is the homeland of the first man? The next book in the series tells about these and many other secrets of the prehistoric world.