PositiveThe New York Times Book Review... Shah explores the history of intellectual connections among all these migration phenomena, tackling with compassion and insight a deeply complex and challenging subject ... The scope of Shah’s story is vast, and she has taken some scientific shortcuts along the way, including a few that undermine her argument. Biologists recognize a diversity of plant and animal movements: daily movement within a home range, annual cyclic migration, dispersal from natal origin to a place of breeding, gene flow among populations of a species, historical range expansion, species dispersal over a geographic barrier, etc. Shah lumps all of these under the concept of \'migration,\' which makes some of her discussion confusing. How does the African origin of so much human diversity relate to the challenges cougars face crossing highways in Los Angeles? Or to the myth of altruistic lemmings leaping into the sea to their deaths? ... Now, there are many reasons a book might make a reader feel hot under the collar, but reading Shah’s dismissal of the impact of invasive species while scratching my neck was a real trigger for me...Although there is evidence for this argument, she fails to engage with the genuine ecological damage that introduced species are causing around the world...Nor does her book address the enormous ecological impact that human migration has already had on the planet ... proof that her work addresses issues of fundamental importance to the survival and well-being of us all.