The Independent newspaper published in England on the 6th of May, 2010, contained an article with the title: “End of the Alaotra grebe is further evidence of sixth great extinction: species are vanishing faster than at any point in the last 65 million years.” It is generally supposed that this loss of species is due to anthropogenic change, and there is great current concern regarding the consequent loss of biodiversity, which motivates the work of this book; see Kolbert (2014).