Knut, the polar bear cub that was raised by hand, has suddenly died in Berlin Zoo, yesterday - 19 March. According to several Zoo visitors he had a seizure and dropped into the water and died, but this has not been confirmed by the Zoo's officials. The cause of death will be established by an autopsy, which is carried out to date. Could it have been stress, because Knut's companions, all females, were not very friendly with him and behaved quite agressive towards him. And was this because he behaved differently, due to being raised by hand (his mother rejected him)? Did he became too familiar with human beings, and their behaviour? There has been a huge controversy back then when he was born. Some said that such a large carnivore species should never be raised by human hands and kept alive, because it was a violation of animal protection legislation. I presume it could have disrupted his behavioural development too, which could have made it hard for him to adapt to polar bear behaviour when he grew up. Others said that it would be a waste to kill the cub, because of the dire situation of the polar bear as a species in the wild, and zoos' contribution to species conservation. And perhaps those people were also anxious to keep the cub alive that made them so proud, and supposedly rich? As it was the first polar bear born on their premises, in their city, since 30 years. Knut was supposed to take part in the Endangered Species breeding Programme of EAZA. I reckon he was nearly ready for being sent to another zoo for breeding purposes. Whatever cause there is for his death, let us hope that lessons can be learnt from his life and his death.