This is an important book. But first a warning: readers should have some basic biological knowledge and part of the book (with many examples and useful digressions) will only appeal to botanists/microbiologists. Prof. Wilson clearly demonstrates that the world's demographic explosion initiated a big extinction of all sort of biological species and that we have to stop this, for biodiversity is priceless. Governments take the biological wealth of their country not serious enough. He states for instance that fewer than 3 percent of the flowering plants of the world have been examined for alkoloids and that many species are at risk. Prof. Wilson illustrates very forcefully the impact of biodiversity by giving numerous examples from the medical, pharmaceutical, energy and agricultural field with colossal numbers in $ for actual applications. To give one example: 'the rosy periwinkle of Madagascar produces two alkaloids that cure most victims of two of the deadliest of cancers, Hodgkin's disease and acute lymphocytic leukaemia. The income from the manufacture and sale of these two substances exceeds $ 180 million a year.' (p.271) This is a very important book for the future of humanity. It cannot be underrated.