Knut with zookeeper
Polar bear Knut with his zookeeper Thomas Doerflein (who had died in 2008) on the day of the first public appearance of the little bear in March 2007.
Knut made his first pubilc appearance at the Berlin Zoo in March 2007. He was born in captivity on Dec. 5, 2006.
Zookeeper Thomas Doerflein cared around the clock for Knut at birth, reportedly sleeping on a mattress next to the tiny fluffball. For the first few months, he was feeding Knut every two hours with a bottle of baby formula mixed with cod liver oil.
Knut weighed just 1.8 pounds (810 grams) at birth, but by age 2 he weighed some 440 pounds (200 kilograms). Here Knut is just a few months old.
Knut at the zoo
Even though Knut's fur looks white, his hair is really made of clear, hollow tubes filled with air.
The Berlin Zoo's beloved polar Bear Knut, whose antics and cute demeanor charmed the world, died unexpectedly over the weekend, on March 19.
Knut at the zoo
Knut at the Berlin Zoo.
Here, polar bear Knut at the Leibniz Institute for Zoo and Wildlife Research Berlin (IZW).
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Jeanna served as editor-in-chief of Live Science. Previously, she was an assistant editor at Scholastic's Science World magazine. Jeanna has an English degree from Salisbury University, a master's degree in biogeochemistry and environmental sciences from the University of Maryland, and a graduate science journalism degree from New York University. She has worked as a biologist in Florida, where she monitored wetlands and did field surveys for endangered species. She also received an ocean sciences journalism fellowship from Woods Hole Oceanographic Institution.