Aristotle was a brilliant philosopher and observer of nature. He pioneered the study of zoology, but he was utterly clueless about bird migration.

The seasonal appearance and disappearance of the birds in his native Greece perplexed him. Similar appearing species must be "transmuted" into each other across seasons, he reasoned, to explain the disappearance of Redstarts each winter when European Robins suddenly arrived. Summer's swallows and storks, which were not replaced by similar species, were thought to hibernate in mud or tree cavities.

In the early 1800s, a White Stork arrived in Germany with a long spear impaled through its neck. The spear was from Central Africa. Rather than flying to the moon, as some thought, the White Stork must have been in Africa for the winter. A worldly view of migratory birds was coming to the fore.

Around the same time, John James Audubon tied some silver string around individual legs of Eastern Wood-Pewees (flycatchers) in order to see if the same birds returned to his Mill Grove, Pennsylvania home the following spring. They did, and with that Audubon launched the study of bird banding that has been central to understanding migratory birds ever since. Migratory birds are faithful to place.

We are now amid a bona fide renaissance in understanding the nature of bird migrations. New tracking technologies, particularly smaller and smaller satellite transmitters - and more recently, Geolocators (which combine light-level loggers with a GPS unit in one tiny package) - have been applied to migrating birds and revealed with great detail their complex geographic movements.

Read the full blog on the Huffington Post >>