Environment: Do Cities Really Need Dogs?

The dog may well be urban man's worst friend. The beast in the city jungle chews children, attacks joggers and howls into the night in a cramped apartment that makes it neurotic. When it does get out—twice a day, if its master can manage—it turns street and sidewalk alike into messy booby traps for pedestrians. The brassy blonde in the film Midnight Cowboy said it all when she coaxed her toy poodle: "Do it for mama."

In cities throughout the world, dogs are fast becoming the most obnoxious minority group. There are 280,000 of them in Tokyo, 300,000 in Los Angeles, 500,000...