chapter  6
Macabre lethality
Pages 22

The deliberate spreading of disease or toxic substances is a stratagem viewed in all cultures as peculiarly ugly and depraved. Traditional mores may allow a bedouin, say, to make off periodically with an adversary’s camels but never to pollute his wells. The roots of this particular proscription may lie in how, during the interminable aridity of the late Pliocene (several million years ago), our hominid ancestors were constrained to leave a shrinking rain forest to resume the survival struggle on the less crowded but desperately parched African plains.