The wandering albatross (Diomedea exulans) has the largest wingspan of any living bird. The largest known specimen of the species, a male caught and measured by the Antarctic research ship USNS Eltanin in the Tasman Sea in 1965, had a wingspan of 11 ft. 11 in. As a result of its impressive wingspan, the wandering albatross is an expert glider and can remain aloft for long periods without beating its wings. In fact, the wandering albatross has sometimes been known to sleep while it flies. Even the wandering albatross, however, can't compete with the extinct South American teratoron (Argentavis magnificens). The teratoron, which existed 6 to 8 million years ago, had an estimated wingspan of 25 feet!