Page 12 - The Miracle of Migration in Animals

THE MIRACLE OF MIGRATION IN ANIMALS

creatures— ranging in weight from 35 to 40 gm (1.2 to 1.4 ounces) in

the case of the lightest, up to 130 tons for the heaviest—travel con-
stantly. Many animals set off on journeys of different lengths for dif-
ferent reasons. Sometimes from one garden to another, from one
nest to another, or from one continent to another. By air: bats, spi-
ders, butterflies, ducks and geese; by land: elephants, zebras, bison,
snakes, frogs and locusts; by sea: lobsters, whales, salmon, sea
urchins and starfish. These migrations all create a necessary balance
in the animals’ lives. The ways in which various species manage to
follow their long and arduous migration routes so perfectly have in-
terested scientists for many years and been the subject of many re-
search projects.

In their search for answers on this subject, scientists encounter
a serious problem. What impels animals to leave their habitat and
use up a great deal of energy and time traveling such distances?
Different species migrate for different reasons. Some set off on
their journeys to find food, while others set off to reach their breed-
ing grounds. Others abandon the environment where they were
born when living conditions change. However diverse the reasons
behind animal migration, there is one common factor: In each and

every animal species from great to small, and in each kind of migra-
tion, great order and skill is evident.

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