Amazing Moms of the Animal Kingdom

Amazing Moms of the Animal Kingdom
Tom Brakefield / Corbis

Harp Seal
As if raising a child on a moving sheet of ice patrolled by polar bears and fur poachers weren't hard enough, the harp seal mom nurses her pup on 48% fat seal milk continuously for 12 days without eating. Her pup will gain an average of 5 lb. (2.3 kg) per day during this 12-day nursing period, while Mom herself will lose about 7 lb. per day.

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