Have bird brains mastered art of quantum physics?
How migratory flights are achieved is a wonder of the world - yet habitats are being casually destroyed
As you read this, flocks of bar-tailed godwits may be departing from the south coast of Alaska. These brown wading birds may seem nondescript - like smaller cousins of curlew - but they are embarking on one of the greatest migratory journeys.
The godwits will fly non-stop for 11,700 km, the distance from Hong Kong to Los Angeles, in the longest known flight by any creature. After eight days, they arrive at their destination, coastal mudflats in New Zealand. Church bells will ring to welcome flocks touching down in Christchurch, where they are seen as harbingers of spring.
Bird migration is among the wonders of the natural world. It has evolved in response to the great rewards of being able to exploit food in a place like Arctic tundra, while also fleeing winter conditions that make life impossible for many birds.
Yet there are immense risks and countless birds die en route.
Migratory birds have a host of remarkable adaptations that enable them to undertake such journeys. To prepare for their autumn marathon, the bar-tailed godwits store energy until fat comprises up to 55 per cent of their body weight. Their livers, kidneys and intestines shrink, becoming almost useless, as the birds' bodies focus on flying.
The godwits also have innate weather forecasting skills.