Elementary elephant control

WHILE many African countries contend with critically low elephant numbers, those in the south of the continent face the opposite problem—soaring pachyderm populations that need regular control. Culling is controversial, as it upsets not just human sensitivities but the strong social bonds of the animals, and has led to delinquent behaviour in motherless young bulls. Relocating whole groups of animals is successful but expensive, as are the latest contraceptive techniques. But a cheap and humane alternative could be to reduce the amount of iodine in the animals' water supply.