Nature's navigators

摘要

New Zealand is home to quite a few long-distance navigators, including humpback whales, two species of eel, two cuckoos, several Arctic waders, and many migratory seabirds. Each one of these creatures possesses an extraordinary ability to find its wayfor thousands of kilometres well beyond its visual horizon. All are capable not only of maintaining orientation (compass bearing) but also establishing their position in relation to a known destination, whether it lies beyond or beneath the sea. This ability is particularly intriguing to humans, for although some of their methods for doing so are biologically available to us, several are not.