ABSTRACT
In the past, when the soil environments and/or climates changed sufficiently to decrease a land's productive capacity, a common response of society was not to mitigate or adapt to the changes but to migrate or flee to other regions of the world in search of food or for lands to grow their food (see Chapters 1 and 10). This 4000–10,000-year history of human migration has been the norm, and an effective approach that allowed humans repeatedly to deal with periods of resource scarcity. When people migrated more than a thousand years ago from the Mediterranean region, they were producing food in areas that were more suitable to grow crops for consumption by family members who remained living in the home country (Wild, 1993). By migrating, humans improved their chances for surviving and probably increased their human development potential. For example, European colonialists who emigrated to North America, especially during the 17th century, were able to increase their socioeconomic status, something that would have been less likely if they had remained in Europe.
