Times: In a televised interview with Sir Trevor McDonald last week, the Duke of Edinburgh cited “overpopulation” as the prime source of escalating food prices. Another gaffe! “Overpopulation” dropped out of usage in the 1970s, and the deluded old coot doesn’t seem to realise that the term is passé. Or is it? Helping to make “overpopulation” a buzz word of his era, Paul Ehrlich observed in his 1968 bestseller The Population Bomb that by 8000BC it had taken the human race about 1m years to …