Page 194 - The Miracle of Migration in Animals

THE MIRACLE OF MIGRATION IN ANIMALS

For the time of the migration, the caribou waits until the condi-
tions are the most favorable—when the ridges are exposed to strong
winds, when the lakes are frozen over, and the snow is either shallow or
crusted. The deeper the snow, the more energy they will have to use.
When forced to walk in deep snow, they march in single file, and an
adult female usually takes the lead. She opens a path in the snow so the
others use less energy following her. After a few hundred meters, an-
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other caribou takes over the lead. This is clever organization, and it
can’t be said that caribou do this of their own free will, displaying self-
sacrificing behavior by conscious agreement among themselves. It is

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