Bar-headed geese rise and fall with the terrain below them when they migrate, scientists report in the Jan. 16 Science. This roller coaster flight pattern saves the birds energy, even though they must repeatedly climb to recover the altitude they lose at each dip in the topography. - Halil

Nice international study, hence why this article in important! -> Paul Nurse accuses politicians of 'cowardice' over scientific evidence http://ff.im/1kPDQ0 - Halil