Portrait of Renaissance children with guinea pig is a first

A painting of three Elizabethan children is believed to be the first to show a pet guinea pig. The portrait dates to 1580. Guinea pigs were brought to Europe by Spanish merchants in the late 1500s, but proof they were kept has pets has only been found recently.

The children, whose identities are unknown, are richly dressed and probably from a wealthy family. One of the boys also holds a bird, which may be symbolic.

The portrait will be part of an exhibit on the Elizabethan people at the National Portrait Gallery in London, England. [photo]