Homes and Property | Home PageFactfile ... on a children's favouriteTom Kelly|Daily Mail13 April 2012 Hamsters have one of the shortest gestation periods of all mammals, at 16 days. Only the opossum, at 13 days, is quicker. They can start breeding at four months old and the average-litter is six to eight although up to 20 have been recorded. So if a pair had an average lifespan of three years, and they and their offspring were allowed to breed unchecked, there would be more than 100,000 of them. Their eyesight is poor but they have sensitive hearing and smell - and they use their whiskers like a cat to help judge tight spots. They are intelligent and may learn to respond to your voice - especially if rewarded with treats With an estimated million of them in British homes, they are the eighth most popular pet. Goldfish come top. In the wild they eat mainly seeds, shoots and root vegetables but will also eat insects and store food in their burrows. In fact, 'hamster' comes from the German word 'hamstern', which means to hoard. A 6FT model of a hamster exhibited in the Millennium Dome was sold for £3,000 at auction. MORE ABOUTMarsupialMillennium DomeO2 Arena