translation.en: If you move the dots down to the bottom of the rectangle you can see that the cities for the existing three billion urban residents take up only three percent of the arable land on earth.
translation.zh: 如果你把这些点移动倒长方形的底端 你发现已经住有30亿城镇居民的城市 只占用了地球上3％可耕种土地