The oldest known gorilla to be born in captivity, a female named Colo, has died in the US aged 60. Colo passed away in her sleep overnight at the Columbus Zoo and Aquarium in Ohio, less than a month after celebrating her birthday. She was born at the zoo in December 1956 and is believed to be the first gorilla ever born in captivity. Colo, a Western lowland gorilla, lived for more than 20 years longer than the average captive gorilla. Despite recently having a malignant tumour removed, zookeepers said that she had been recovering well and the cause of...