A set of generalizations concerning migration patterns was formulated in the late 19th century. These observations describe various aspects of human movement, including the distance migrants travel, the reasons for migration, and the characteristics of migrants. These principles provide a foundational framework for understanding migration flows and their impact on both origin and destination areas. For example, the principle of distance decay suggests that migrants are more likely to move shorter distances, often within the same country, rather than embarking on long-distance international migrations. This can be observed in rural-to-urban migration patterns within a region.
The value of these generalizations lies in their ability to offer a simplified, yet insightful, perspective on complex migration dynamics. They provide a starting point for analyzing migration trends, understanding the selective nature of migration (e.g., who migrates and why), and predicting future migration flows. Historically, these observations were instrumental in shaping early migration theory and continue to inform contemporary research. They help clarify that migration is not random, but is influenced by a variety of factors. One key benefit to understanding them is being able to better comprehend population distribution patterns and how they change over time.