They are vital feeding grounds on migration flyways for shorebirds travelling between the Arctic and Africa. |
At the height of glaciation the Bering land bridge potentially permitted migration of mammals, including people, to North America from Siberia. |
The outward migration of people from the city has hurt the city's economy greatly. |
Barbarian migration stabilized in much of Europe, although Northern Europe was greatly affected by the Viking expansion. |
In general, the depositional history of the Gulf Coast has been one of overall gulfward migration of the shoreline and Continental Shelf edge. |
The primary physiological cue for migration are the changes in the day length. |