Zoos, as we are all being told in these animal sensitive times, are imprisoning institutions whose main value is to preserve endangered species and provide somewhere to go for separated fathers whose turn is to look after the kids for the weekend.
So that provides two explanations for Ken Livingstone's decision to marry, at last, Emma Beal, the mother of two of his children, in the precincts of London Zoo next month. We all know, of course, the ex-London Mayor's love of animals, his association with newts, and his childhood dream of becoming a zookeeper.
But what is one to make of his choice of venue inside the zoo, in the Mappin Pavilion, surrounded by wallabies and emus. They may be fine as a nostalgic reminder of the couple's first foreign trip together down under. But to announce it during the last Test of the Ashes series? You need look no further for an explanation of Red Ken's fall from political grace.