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Challenge question #1susamel@juno.comMon, 2 Mar 1998 22:49:07 -0500
then they must know by the sun. As the photoperiod elongates and lessens, telling them it is winter or summer, their internal clocks are stimulated and the cranes move. We also thought that the crane's clocks might be started by the end of the breeding season and the maturing of their young.
Anna Roszkowski
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