The modern landscape of the Scottish Highlands is one of the most distinctive in Britain. The appearance of the Highlands clearly owes much to its distinctive geology and climate, and particularly to the ice ages which have produced the features of glacial erosion and deposition that are so prominent today. In the south and east agricultural improvement was conducted on a model derived from the adjoining Lowlands. It is also necessary to understand something of the nature of traditional Highland society in order to appreciate how this influenced the landscape. In an area in which land was the principal, almost the only, source of income in the early eighteenth century, many Highland proprietors began seeking other means of increasing their incomes. Displacement of population often accompanied schemes for farm amalgamation undertaken to improve cattle rearing and mixed farming in the southern and eastern Highlands, as well as in conjunction with the establishment of planned villages.