There has been enough time for it to evolve from scratch 1,500 times in succession within any one lineage. For centuries, many people have argued that the intricate design we observe in nature could not have occurred by accident. It is Darwinian natural selection. Behind the question there is always an unspoken, but never justified implication that since science is unable to answer 'why' questions, there must be some other discipline that is qualified to answer them. This implication is, of course, quite illogical. . . .
Questions can be simply inappropriate, however heartfelt their framing.
I don't want to give the impression that this book is a polemic, because it is not. Most of it is a carefully reasoned, meticulous presentation of how evolution explains biology, with equal credit to Darwin and to James Watson and Francis Crick, who unraveled DNA some 40 years ago. When Darwin published his Theory of Evolution in the mid-19th Century, he did not have a clue about the mechanism of heredity. A hundred years later, Watson and Crick figured out how heredity works on the molecular level, and it turned out to be one of the greatest examples of confirmation in the history of science. Every living thing on Earth has the same genetic code in its genes.