Manning distinguishes three major types of migration&colon; labor migration, refugee migrations, and urbanization. This migration is regarded as one of the largest peaceful migrations in the world's history. Prolonged droughts have caused mass migrations and humanitarian crisis. The wars caused large population migrations, mostly involuntary. Swarms have devastated crops and been a contributory cause of famines and human migrations. It appears there were two distinct oceanic migrations from the mainland to Madagascar. Such geographic analysis works best in the absence of recent large-scale, rapid migrations. France has been influenced by the different human migrations that occurred throughout Europe over time. The periods of the most important migrations are contested. Two south to east migrations are discernible within haplogroup L0. More recent migrations has added even more languages. Their larger migrations are subject to ocean currents. Canada geese are known for their seasonal migrations. The British Empire was also responsible for large migrations of peoples. There are several hypotheses concerning Apache migrations.