Experiments at the University of Massachusetts show that, if an adolescent golden hamster is left in a cage with an aggressive adult hamster for an hour each day, it will grow up to become a bully: it will pick on animals smaller than itself, but will cower in fear around hamsters its own size. As far as these experiments were concerned, a hamster's adolescence starts around 25 days of age.
The Golden (or Syrian) hamster was discovered in Aleppo, Syria, in 1930 by Professor Aharoni and the first group of their descendants was smuggled into the UK in 1932 in the pocket of a zoologist. It is by no means certain that all domestic hamsters are descendants of this original group, since several other groups of Syrian hamsters were brought into the UK later.
Originally, all Syrian hamsters were short haired, but breeding techniques have led to the recognition of four types of fur today: short haired, long haired, satin and rex (curly, frizzy). Long-haired male hamsters have longer fur than long-haired female hamsters.
Hamsters are the third most common animals to be used in experiments after mice and rats.
On 12 July 1992, the pet hamster in a South Glamorgan school died of a heart attack, apparently caused by the shock of a teacher firing a starting pistol in a school sports day rehearsal.