A world survey course with a message: Change your attitude if you want Homo sapiens to survive another million years. Tudge (The Engineer in the Garden, p. 69, etc.) is an English science writer and broadcaster who soaks up data like a Pentium chip and is eager to disgorge all for the lay reader. The result is an encyclopedic volume that encompasses geology, meteorology, paleontology, taxonomy, and ecology, concluding with some predictions for the future. His basic thesis is that the human lot began to be cast not when written history began, some 10,000 years ago, but through millennia of prehistory, when fully modern humans and the basis of human culture (tool-making, agriculture, etc.) existed, and earlier: The moderns, in turn, were the product of evolutionary changes dating to the ape-hominid split five million years ago. You know from the start his heart is in the right place when he refers to historian of science Misia Landau's observation that much of what is purported to be objective human science smacks of myths that glorify human achievement. Bearing that in mind, Tudge's early chapters emphasize the role of earth forces and weather in moving continents, in creating mountains, in forcing migrations, or causing major die-offs as asteroids hit. Later chapters fairly present rival theories of human evolution, with Tudge offering his own spin in the form of successive ""out of Africa"" migrations. A recurrent theme is the role humankind now plays in Earth's destiny, whether through CFCs in the atmosphere or the deliberate or inadvertent destruction of species. Only recognition of what is at risk and a change in attitude will rectify the situation, argues Tudge, in an admittedly not very hopeful stance. Tudge's zeal to explain in detail and present mountains of evidence will try the reader who may wonder if this isn't a text with quizzes to follow. All in all, however, this is sound science supporting a point of view that deserves to be heeded.