Page 56 - The Miracle of Migration in Animals

THE MIRACLE OF MIGRATION IN ANIMALS

At a temperature of -40°C (-40°F)
at dizzying heights, a bird’s
feathers provide it with thermal
insulation. Also, their hollow
bones compensate for changes
in air pressure at high altitudes.

(-58°F), and migrating birds may have to endure these freezing condi-
tions for a number of days. 14
Every living creature is created to have enough strength to deal
with the difficulties it may encounter throughout its life. Geese can
fly at an altitude where there is little oxygen and sometimes at freez-
ing temperatures thanks to the special structure of their bodies. This
structure is not the product of unconscious coincidences—in short,

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