Migratory birds 'detect' latitude and longitude
You may have to use the compass to locate the latitude and longitude of a place, but migratory birds can detect the coordinates without any instrument.Updated: Feb 04, 2008 15:44 IST
You may have to use the compass to locate the latitude and longitude of a place, but migratory birds can detect the coordinates without any instrument.
A team of international researchers has found that the migratory birds are true navigators, meaning they can identify at least two coordinates that roughly correspond to latitudes and longitudes.
The findings challenge the notion held by some that birds might be limited to nin the north-south direction. But the team still don't know how they do it.
"We have experimentally shown beyond reasonable doubt that long-distance, intercontinental avian migrants can correct for east-west displacements during their return migration in spring.
"This means that they can determine geographical longitudes, even though we do not currently know how they do it," lead researcher Nikita Chernetsov of the Biological Station Rybachy at the Zoological Institute in Russia was quoted by the 'ScienceDaily' as saying.
The team released a group of Eurasian reed warblers captured during their spring migrations. They found that after being flown 1,000 kms to the east, the birds corrected their displacement by shifting their orientation from the northeast to the northwest -- their original destination.
According to Chernetsov, "Our results suggest that Eurasian reed warblers are able to determine longitudes and perform bicoordinate navigation.
"This finding is surprising and presents a new intellectual challenge to bird migration researchers, namely which cues enable birds to determine their east-west position?"