Page 45 - The Miracle of Migration in Animals

HARUN YAHYA

To reach the peaks of the Alps, these little creatures must be able
to predict the arrival of cold fronts, moving in a southeasterly direc-
tion, that will help carry them to their summer resting ground.
Scientists believe that these insects’ ability to detect changes in baro-
metric pressure or air ions enables them to make accurate predictions.
A similar barometric sense also exists in the ears of birds. When
migrating, birds are so sensitive to even the slightest change in alti-
tude that they can continue flying within a narrow air corridor 17 me-
ters (56 feet) high, even if their vision of the ground is obscured by
clouds. If we humans had the sensitivity of a pigeon or a duck, we
could tell what floor of a building we were on by the change in air

pressure.
Just as a bird uses its pressure sense for predicting altitude, it is
also helpful in forecasting the weather. A sudden fall in atmospheric
pressure occurs just before most winter storms, and birds perceiving
this pressure drop prepare for the difficult journey ahead. A wrong
guess can prove fatal for migrants. When spring comes to the
Northern Hemisphere, birds get ready to migrate only when the tem-
perature rises, the pressure falls and a southerly wind is blowing. 10

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